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Summary of Content
Factory Workshop Manual
Make
Chevrolet
Model
K Tahoe 4wd
Engine and year
V8-5.3L VIN T (2002)
Please navigate through the PDF using the options
provided by OnlyManuals.com on the sidebar.
This manual was submitted by
Anonymous
Date
1st January 2018
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions
Accessory Delay Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 8
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 9
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 10
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 11
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 12
Accessory Delay Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Accessory Delay Module > Component Information > Diagrams > Diagram Information and Instructions > Page 13
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Accessory Delay Module: Description and Operation
RETAINED ACCESSORY POWER (RAP) POWER MODE
RAP is a vehicle power mode that permits the operation of selected customer convenience items
after the ignition switch is turned OFF. These selected items will remain in operation until a
passenger compartment door is opened or until the RAP function timer reaches its shut-off limit.
The body control module monitors the ignition switch position, battery condition and passenger
compartment door status to determine whether RAP should be initiated. If the ignition switch
transitions from RUN/ON to OFF, the battery level is within the acceptable range and the
passenger compartment doors are closed, the body control module closes the RAP relay.
This provides power for the following: ^
Sunroof
^ Power windows
^ Power door locks
^ Radio
^ Rear radio
^ OnStar
The BCM turns OFF the RAP function and opens the RAP relay when one of the following
conditions are met: ^
The BCM senses the opening of any door or the liftgate.
^ The BCM detects a decrease in battery capacity below a prescribed limit.
^ The BCM receives a message from its internal timer indicating the end of the RAP period after 20
minutes.
^ The transition from OFF to RUN/ON or ACC of the ignition switch.
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Accessory Delay Module: Initial Inspection and Diagnostic Overview
Diagnostic Starting Point - Accessory Delay Module
Begin the system diagnosis with the Diagnostic System Check Accessory Delay Module. The
Diagnostic System Check will provide the following information:
^ The identification of the control module which commands the system
^ The ability of the control module to communicate through the serial data circuit
^ The identification of any stored DTCs and their status
The use of the Diagnostic System Check will identify the correct procedure for diagnosing the
system and where the procedure is located.
Diagnostic System Check - Accessory Delay Module
DIAGNOSTIC SYSTEM CHECK - ACCESSORY DELAY MODULE
TEST DESCRIPTION
Steps 1-5
The numbers below refer to the step numbers on the diagnostic table. 2. Lack of communication
may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of
the class 2 serial data
circuit. The specified procedure will determine the particular condition.
4. This step is checking for DTCs in the BCM. 5. This step is checking for RAP specific DTCs.
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Page 41
Accessory Delay Module: Symptom Related Diagnostic Procedures
A Symptoms - Accessory Delay Module
IMPORTANT PRELIMINARY CHECKS BEFORE STARTING
1. Perform the Diagnostic System Check - Retained Accessory Power before using the Symptom
Tables in order to verify that all of the following are
true: ^
There are no DTCs set.
^ The control module(s) can communicate via the serial data link. See: Initial Inspection and
Diagnostic Overview/Diagnostic System Check - Accessory Delay Module
2. Review the system operation in order to familiarize yourself with the system functions. Refer to
Retained Accessory Power (RAP) Description and
Operation.
VISUAL/PHYSICAL INSPECTION
^ Inspect for aftermarket devices which could affect the operation of the Retained Accessory Power
system. Refer to Checking Aftermarket Accessories in Diagnostic Aids.
^ Inspect the easily accessible or visible system components for obvious damage or conditions
which could cause the symptom.
INTERMITTENT
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing
for Intermittent and Poor Connections in Diagnostic Aids.
SYMPTOM LIST
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:
^
Retained Accessory Power (RAP) On After Timeout
^ Retained Accessory Power (RAP) Inoperative
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Accessory Delay Module > Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview >
Page 42
Steps 1-10
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Page 43
Steps 1-9
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Page 44
Accessory Delay Module: Scan Tool Testing and Procedures
Scan Tool Data Definitions
MODULE INFORMATION 1
Julian Date of Build: The scan tool displays the date upon which the Body Control Module (BCM)
was manufactured.
Manufacture Enable Counter (MEC): The scan tool displays the actual value for the MEC in the
BCM. This information is for the assembly plant only.
Module Part Number: The scan tool displays the part number assigned to the BCM that is currently
in the vehicle.
Software Design Suffix: The scan tool displays the version of the software part number in the BCM.
Software Part Number: The scan tool displays the software identification number (ID) in the BCM.
MODULE INFORMATION 2
Retained Accessory Power (RAP) Calibration Number: The scan tool displays the RAP calibration
part number in the BCM.
Retained Accessory Power (RAP) Suffix: The scan tool displays the RAP identification number in
the BCM.
DATA
Battery Voltage: The scan tool displays the battery system voltage.
Inadvertent Power Timer: The scan tool displays the seconds left before the BCM turns the
inadvertent power relay OFF. The BCM uses this feature to protect the battery against inadvertent
battery rundown caused by components that are part of the courtesy lamp circuit. The inadvertent
power relay is supplied power by the BCM for 2400 seconds / 40 minutes after the ignition is turned
OFF.
RAP Timer: The scan tool displays the seconds left before the BCM turns the RAP relay OFF. The
BCM uses this feature to allow the operation of the radio and the power windows for up to 1198
seconds / 20 minutes after the ignition is turned OFF. After the time has elapsed or the door is
opened the BCM will open the ground circuit for the RAP relay.
INPUT 1
Door Handle Switch: The scan tool displays the position of the door handle. The scan tool displays
ACTIVE when a door handle is raised and INACTIVE with all doors closed and the door handles at
rest.
Drivers Door Jamb Switch: The scan tool displays the position of the drivers door. The scan tool
displays ACTIVE when the drivers door is open.
Ignition 1: The scan tool displays the position of the ignition switch. The scan tool displays ACTIVE
when the ignition switch is in the RUN or CRANK position.
Ignition 3: The scan tool displays the position of the ignition switch. The scan tool displays ACTIVE
when the ignition switch is in the RUN position only. Ignition Power Mode: The scan tool displays
the position of the ignition switch. The scan tool displays OFF, RUN, CRANK and UNKNOWN. The
UNKNOWN display is when the BCM can not determine the position of the ignition switch.
Key In Ignition: The scan tool displays the position of the ignition key in the ignition switch cylinder.
The scan tool displays YES when the ignition key is completely inserted into the ignition switch
cylinder. The BCM uses this data in controlling the operation of the reminder chime feature.
RAP Relay Feedback: The scan tool displays the state of the RAP relay. The scan tool displays ON
when the BCM activates the RAP relay.
OUTPUTS
RAP Relay: The scan tool displays the commanded state of the RAP relay. The scan tool displays
ON when the BCM allows the RAP relay to go to ground. The BCM will allow operation of the radio
and the power windows with the ignition OFF and the doors closed for up to 1198 seconds,
approximately 20 minutes.
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Page 45
Scan Tool Data List
Scan Tool Output Controls
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Alarm
Module, (Vehicle Antitheft) > Component Information > Locations
Locations View
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Theft Deterrent Control Module
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Alarm Module: Service and Repair
THEFT DETERRENT CONTROL MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Disable the SIR. Refer to Disabling the SIR System in Restraint Systems. 2. Remove the
steering column trim covers. 3. Remove the ignition lock cylinder. 4. Remove the theft deterrent
control module wiring harness from the steering column harness. 5. Disconnect the electrical
connector from the theft deterrent control module. 6. If, necessary, disconnect the electrical
connector from the ignition lock cylinder case. 7. Remove the theft deterrent module (2) away from
the lock cylinder housing (1).
INSTALLATION PROCEDURE
1. Install the theft deterrent control module (2), onto the lock cylinder housing (1). 2. Install the theft
deterrent control module wiring harness to the steering column harness. 3. If, necessary,
disconnect the electrical connector from the ignition lock cylinder case. 4. Connect the electrical
connector. 5. Install the ignition lock cylinder. 6. Install the steering column trim covers. 7. Enable
the SIR system. Refer to Enabling the SIR System in Restraint Systems. 8. Program the new theft
deterrent control module. Refer to Programming Theft Deterrent System Components. See:
Testing and
Inspection/Programming and Relearning
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Antenna Control Module > Component Information > Service and Repair
Antenna Control Module: Service and Repair
RADIO ANTENNA MODULE REPLACEMENT
REMOVAL PROCEDURE
The Radio control module and the Radio Antenna module cannot be replaced individually. 1. Lower
the rear of the headliner. Refer to Headliner Replacement in Interior Trim. 2. Disconnect the wire
harness (2) attached to the rear quarter glass panel. 3. Remove the module (3) retaining bolt. 4.
Disconnect the antenna cable from the module. 5. Remove the antenna module from the roof. 6.
Remove the radio control module.
INSTALLATION PROCEDURE
1. Install the radio control module. 2. Install the antenna module to the roof.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the module retaining bolt.
Tighten Tighten the retaining bolt to 9 N.m (80 lb in).
4. Connect the antenna cable to the module (3).
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5. Connect the wire harness (2) to the rear quarter glass panel. 6. Install the rear of the headliner.
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Emergency Contact Module > Component Information > Technical Service Bulletins > Recalls: > 08089C > Nov > 08 >
Campaign - Deactivation Of Analog OnStar(R)
Technical Service Bulletin # 08089C Date: 081118
Campaign - Deactivation Of Analog OnStar(R)
# 08089C: Special Coverage Adjustment - Analog OnStar Deactivation (Nov 18, 2008)
Subject: 08089C -- SPECIAL COVERAGE ADJUSTMENT - ANALOG ONSTAR(R)
DEACTIVATION
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Models
The service procedure in this bulletin has been revised. Step 11 in the procedure for the 2004-2005
Saab 9-3 (9440) Convertible has been revised. Discard all copies of bulletin 08089B, issued
September 2008.
Condition
In November 2002, the U.S. Federal Commissions (FCC) ruled that wireless carriers would no
longer be required to support the analog wireless network beginning in 2008. As a result, On
Star(R) is unable to continue analog service.
OnStar(R) has deactivated most of the systems operating in the analog mode; however, there are
some vehicles that OnStar(R) could not deactivate. Although the analog OnStar(R) hardware in
these vehicles can no longer communicate with OnStar(R), the hardware in the vehicle is still
active. If the OnStar(R) emergency button is pressed, or in the case of an airbag deployment, or
near deployment, the customer may hear a recording that OnStar(R) is being contacted. However,
since analog service is no longer available, the call will not connect to OnStar(R). To end the call,
the customer must press the white phone or white dot button. If the call is not ended, the system
will continue to try to connect to OnStar(R) until the vehicle battery is drained.
Special Policy Adjustment
At the customer's request, dealers/retailers are to deactivate the OnStar(R) system. The service
will be made at no charge to the customer.
This special coverage covers the condition described above until December 31, 2008 for all
non-Saab vehicles; April 30, 2009 for all Saab vehicles.
Vehicles Involved
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Campaign - Deactivation Of Analog OnStar(R) > Page 66
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Campaign - Deactivation Of Analog OnStar(R) > Page 67
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Campaign - Deactivation Of Analog OnStar(R) > Page 68
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Campaign - Deactivation Of Analog OnStar(R) > Page 69
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Campaign - Deactivation Of Analog OnStar(R) > Page 70
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Campaign - Deactivation Of Analog OnStar(R) > Page 71
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Campaign - Deactivation Of Analog OnStar(R) > Page 72
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Campaign - Deactivation Of Analog OnStar(R) > Page 73
Involved are certain vehicles within the VIN breakpoints shown above.
PARTS INFORMATION -- Saab US Only
Customer Notification
General Motors will notify customers of this special coverage on their vehicles (see copy of typical
customer letter shown in this bulletin - actual divisional letter may vary slightly).
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Campaign - Deactivation Of Analog OnStar(R) > Page 75
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Campaign - Deactivation Of Analog OnStar(R) > Page 76
Claim Information - GM, Saturn Canada and Saab Canada Only
Claim Information - Saturn US Only
Customer Reimbursement Claims - Special Attention Required
Customer reimbursement claims must have entered into the "technician comments" field the CSO
# (if repair was completed at a Saturn Retail Facility) date, mileage, customer name, and any
deductibles and taxes paid by the customer.
Claim Information - Saab US Only
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Campaign - Deactivation Of Analog OnStar(R) > Page 77
1. To receive credit, submit a claim with the information above.
Disclaimer
2001 and Older Model Year Vehicles (Except Saab Vehicles)
2001 and Older Model Year Vehicles (Except Saab Vehicles)
Important:
2001 and older model year vehicles require the removal of the battery power from the OnStar(R)
vehicle interface unit (VIU) to eliminate the possibility of an inadvertent OnStar(R) or
emergency/airbag call.
1. Locate and gain access to the OnStar® VIU. Refer to OnStar Vehicle Interface Unit
Replacement in SI.
Important:
Complete removal of the VIU is usually not required. Perform only the steps required to gain
access to the C2 32-way blue connector. Residing in the C2 connector are the battery positive (+)
circuits. Removal of the C2 connector will deactivate the unit and eliminate the possibility of an
inadvertent OnStar(R) or emergency/airbag call.
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Campaign - Deactivation Of Analog OnStar(R) > Page 78
2. Disconnect the C2 32-way blue connector from the VIU and tape the connector to a secure
location. Refer to Cellular Communications Connector End Views and related schematics in SI, if
required.
Important:
DO NOT perform the OnStar(R) reconfiguration and/or programming procedure.
3. Secure the VIU in its original brackets and/or mounting locations and reinstall the VIU and
interior components that were removed to gain access to the VIU. Refer to OnStar Vehicle
Interface Unit Replacement in SI.
2002 Through 2006 Model Year Vehicles (Except Saab Vehicles)
2002 through 2006 Model Year Vehicles (Except Saab Vehicles)
Important:
The Tech 2 diagnostic tool must be updated with version 28.002 or later in order to successfully
perform the VCIM setup procedure and disable the analog system.
1. Connect the Tech 2 to the data link connector (DLC), which is located under the instrument
panel of the vehicle.
2. Turn the Tech 2 ON by pressing the power button.
Important:
Tech 2 screen navigation to get to the setup procedure depends on the year and make of the
vehicle. The actual name of the setup procedure (Setup New OnStar or VCIM Setup) depends on
model year and vehicle make as well. Example Tech 2 navigation to the setup procedure Tech 2
screen is provided below.
^ Diagnostics >> (2) 2002 >> Passenger Car >> Body >> C >> OnStar >> Special Functions >>
Setup New OnStar >>
^ Diagnostics >> (5) 2005 >> Passenger Car >> (4) Buick >> C >> Body >> Vehicle Comm.
Interface Module >> Module Setup >> VCIM Setup >>
3. Setup VCIM using the Tech 2. Follow on-screen instructions when you have reached the setup
Tech 2 screen.
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
1. Remove the ground cable from the battery's negative terminal.
2. Apply the handbrake brake.
3. Detach the floor console.
4. Remove the switch and the floor console:
3.1. Twist loose the immobilizer unit (A), bayonet fitting. Unplug the unit's connector.
3.2. Remove the ignition switch cover (B) by first undoing the rear edge of the cover and then
unhooking the front edge. Unplug the ignition
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switch lighting connector.
3.3. Undo the floor console's retaining bolts (C).
3.4. Take out the rear ashtray/cover (D).
3.5. Remove the screw (E) for the rear cover.
3.6. Remove the floor console's retaining nuts (E).
3.7. Detach the floor console (G) by pulling it straight back and lifting it slightly.
3.8. If required, detach the switch for the rear seat heater and unplug the connector.
4. Remove the switch and the floor console:
4.1. Detach the window lift module (A) by loosening it in the front edge (snap fastener). Unplug the
window lift module's connector.
4.2. Detach the switch for the roof lighting (B) and unplug its connector. Lift away the floor console.
5. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
5.1. Unplug the SRS control module's connector (A).
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5.2 Cut off the cable tie (B), detach the connector's rear end face (C) and pull out the connecting
rail (D).
5.3. Remove pin 39, cut off the cable terminal and insulate the end with tape (E). Fold back the
cable and secure it with tape (F).
5.4. Fit the connecting rail and end face.
5.5. Plug in the connector (A) and secure the cables with cable ties (B).
6. Install the floor console over the handbrake. Do not press the console down into place, but
instead allow it to fit loosely.
7. Install the switch:
7.1. Install the switch for the roof lighting (B) and plug in its connector.
7.2. Guide the connectors for the window lift module and rear seat heater, if equipped, through the
hole for each respective unit. Plug in the window lift module's connector and install the module (A).
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7.3. If equipped, connect the rear seat heater's connector and install the switch.
8. Install the floor console:
8.1. Install the floor console's retaining bolts (C) and retaining nuts (F).
8.2. Align the rear cover; make sure that the air duct connects firmly to the air nozzle. Screw in the
cover (E).
8.3. Install the ashtray/cover (D).
8.4. Install the ignition switch cover (B).
8.5. Plug in the immobilizer unit (A) connector. Install the unit, bayonet fitting.
9. Remove the OnStar(R) control modules and secure the wiring:
9.1. Remove the right-hand rear luggage compartment trim in accordance with WIS - 8.
Body - Interior equipment - Adjustment/Replacement.
9.2. Unplug the connectors (A) from the OnStar(R) control modules.
9.3. Remove the console (B) together with the OnStar(R) control modules.
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Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
9.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
9.5. Install the right-hand rear luggage compartment in accordance with WIS - 8. Body - Interior
equipment - Adjustment/Replacement.
10. Install the ground cable to the battery's negative terminal.
11. Clear the diagnostic trouble codes.
12. Set the date and time, see WIS - 3. Electrical system - Information display (SID_ - Technical
description.
2003-2005 Saab 9-3 (9400) 4D/5D; 2004-2005 Saab 9-3 (9400) CV
2003-2005 Saab 9-3 (9440) 4D/5D; 2004-2005 Saab 9-3 (9440) CV
Notice:
Handle the fiber optic cables with care or the signal may be distorted.
^ It is very important that the two leads in the connector are not confused with one another.
^ Do not splice the cables.
^ Do not bend the cable in a radius smaller than 25 mm (1 in).
^ Do not expose the cable to temperatures exceeding 185°F (85°C).
^ Keep the cable ends free from dirt and grime.
^ Do not expose the cable to impact as this may cause the transparent plastic to whiten, thereby
reducing the intensity of the light and causing possible communication interruptions.
^ The cable should not lie against any sharp edges as this may cause increased signal attenuation.
1. Remove the ECU CU with a Tech 2(R) according to the following: Fault diagnosis - Select model
year - Select Saab 9-3 Sport (9440) - All - Add/Remove - Control Module - CU/PU - Remove.
2. Remove the ground cable from the battery's negative terminal.
3. Remove the floor console in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
4. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
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4.1. Unplug the SRS control module's connector (A).
4.2. Cut off the cable tie (B), detach the connector's rear end face (C), and pull out the connecting
rail (D).
4.3. Extract pin 15, cut off the cable terminal and insulate the end with tape (E). Fold back the cable
and secure it with tape (F).
4.4. Fit the connecting rail and end face.
4.5. Plug in the connector (A) and secure the cables with cable ties (B).
5. Remove the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6. M03: Replace the optic cable on the right-hand side
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Important:
Secure the wiring harness so that there is no risk of chafing or rattling.
6.1. Remove the passenger seat in accordance with WIS 8. Body - Seats Adjustment/Replacement.
6.2. Remove the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.3. Remove the right-hand C pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.4. Fold the rear seat backrest forward.
6.5. Remove the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.6. Remove the A-pillar's lower side piece.
6.7. Open the cover on the right-hand wiring harness channels.
6.8. Loosen the locking strip (A) on the 2-pin connector (H2-11) for the optic cable, located by the
right-hand A-pillar.
6.9. Loosen the catch (B) and remove the optic cable that runs backward in the car.
6.10. Dismantle the end cap from the new optic cable (12 783 577) and connect it to the connector
H2-11. Push in the optic cable and make sure
the catch (B) locks and refit the locking strip (A).
6.11. Secure the connector and the old optic cable using the cable tie for the existing wiring
harness (C).
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.12. Place the optic cable in the wiring harness channels on the right-hand side. Thread through
the existing cable ties (C) if possible, otherwise,
secure with a cable tie to the existing one. Close the cover on the channels. Ensure the catches
lock.
6.13. Secure the optic cable along the right-hand rear wheel housing, next to the ordinary wiring
harness securing points and by the SRS unit (D).
6.14. Thread the optic cable up next to the safety belt by the old optic cable and place on the parcel
shelf.
6.15. Unplug the connectors (E) from the OnStar(R) control modules.
6.16. Remove the console (F) together with the OnStar(R) control modules.
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.17. Fold back the wiring harness and tape over the connectors (G). Fold back the wiring harness
once more and secure with cable ties (H).
6.18. Secure the new optic cable on the parcel shelf along the existing wiring harness by the
ordinary securing points and by the speaker (I).
6.19. Thread the optic cable down next to the old cable from the parcel shelf to the left-hand wheel
housing, next to REC. The cable is secured in
the existing clips.
6.20. Fit the right-hand C-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.21. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.22. Fit the passenger seat in accordance with WIS - 8. Body - Seats - Adjustment/Replacement.
6.23. Fit the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.24. Fold up the rear seat backrest.
6.25. Fit the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.26. Fit the A-pillar's lower side piece.
7. M04-05, 4D: Removing the OnStar® control modules and securing the wiring:
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7.1. Remove the console (A) together with the OnStar(R) control modules.
7.2. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
7.3. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
7.4. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
8. CV: Removing the OnStar(R) control modules and securing the wiring:
Adjustment/Replacement.
8.1. Open the luggage compartment floor.
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Campaign - Deactivation Of Analog OnStar(R) > Page 88
8.2. Remove the console (A) together with the OnStar(R) control modules.
8.3. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
8.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
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Campaign - Deactivation Of Analog OnStar(R) > Page 89
8.5. Close the luggage compartment floor.
9. Fold down the left-hand rear side hatch in the luggage compartment.
10. M03: Replace the optic cable on the left-hand rear side:
10.1. Place the optic cable so that it is positioned behind the terminal housing on top of REC (A).
10.2. Remove the locking strip (B) on the 2-pin connector (H2-9) for the optic cable.
10.3. Open the terminal housing (C) with a screwdriver. Remove the secondary catch (D) on the
connector and disconnect the optic cable coming
from the OnStar(R) control modules.
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Campaign - Deactivation Of Analog OnStar(R) > Page 90
10.4. Remove the end cap from the new optic cable, connect to the connector and refit the
secondary catch (D). Fit the terminal housing (C) to the
connector and refit the locking strip (B).
10.5. Secure the old optic cable together with the new one (E).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
11. CV: Remove the rear seat in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement. The O-bus connector H2-9 is located behind the left speaker.
12. M04-05: Disconnect the optic cables on the OnStar(R) control modules and join the cables:
12.1. Cut off the cable tie holding the connector (H2-9) against REC.
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12.2. Cars with brackets for e.g. an amplifier: Remove the pin strap (A) from the bracket and
remove the tape (B) holding the optic cables.
12.3. Remove the locking strip (C) on the 2-pin connector (H2-9). Open the terminal housing with a
screwdriver. Remove the secondary catch (E)
on the connector and remove the optic cables coming from the OnStar(R) control modules.
12.4. Loosen one of the optic cables remaining in H2-9 (F), connect it to the connector and fit the
secondary catch (E). Connect the connector so
that the optic cables are opposite each other (G). Connect the terminal housing (D) and refit the
locking strip (C).
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Campaign - Deactivation Of Analog OnStar(R) > Page 92
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.5. Cars with brackets for e.g. an amplifier: Fit the cable tie (11 900 515) to the wiring harness
approx. 100 mm (4 in) from H2-9, fit the cable
tie (H) to the bracket. Gather the optic cable in a gentle loop (I) and then place the loop behind the
bracket.
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.6. Cars without brackets for e.g. an amplifier: Gather the optic cable in a gentle loop (J) and
secure with cable tie.
13. CV: Fit the left-hand, rear side hatch trim in accordance with WIS - 8. Body - Interior equipment
- Adjustment/Replacement.
14. Fit the ground cable to the battery's negative terminal.
15. Carry out procedures after disconnecting the battery, see WIS - 3. Electrical System - Charging
system - Adjustment/Replacement.
Important:
Follow Tech 2(R) on-screen instructions.
16. Add ECU ICM, choose without OnStar(R). See WIS-General-Tech 2(R) - Description and
Operation - Add/Remove.
2000-2004 Saab 9-5
2000-2004 Saab 9-5
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Campaign - Deactivation Of Analog OnStar(R) > Page 93
1. Remove the ground cable from the battery's negative cable.
2. Remove the center console, see WIS - Body - Interior.
3. Loosen the gear shift housing (A).
AUT: Disconnect the 6-pin connector (B) to improve access to the gear shift housing screws.
4. Disconnect the signal cable from the SRS control module to the OnStar(R) control module and
secure the cable.
4.1. Disconnect the connector (A) from the SRS control module and cut the cable tie (B).
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Campaign - Deactivation Of Analog OnStar(R) > Page 94
4.2. Release the back end of the connector (C) and remove from the contact rail (D).
4.3. M00-01: Disconnect pin 39, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.4. M02-04: Disconnect pin 58, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.5. Assemble the contact rail and end.
4.6. Connect connector (A) and secure the cable using a cable tie (B).
5. Assemble the gear shift housing (A).
AUT: Connect connector (B).
6. Assemble the center console, see WIS - Body - Interior.
7. Remove the OnStar(R) control module and secure the cable harness:
7.1. 5D: Remove the right-hand cover from the luggage compartment floor.
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Campaign - Deactivation Of Analog OnStar(R) > Page 95
7.2. Remove the console (A).
7.3. Disconnect the connector (B) from the OnStar(R) control module.
Important:
Secure the cable harness to prevent the risk of scraping and rattling.
7.4. Fold back the cable harness and tape down the connector (C). Fold back the cable harness
again and secure with cable ties (D).
7.5. 5D: Assemble the right-hand cover for the luggage compartment floor.
8. Fit the ground cable on the battery's negative cable.
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9. Erase the diagnostic trouble codes.
10. Set the date and time, see WIS - 3. Electrical system - Information display (SID) - Technical
description.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 05-08-46-004C
> Dec > 10 > OnStar(R) - Number Incorrect/Incorrectly Assigned
Emergency Contact Module: Customer Interest OnStar(R) - Number Incorrect/Incorrectly Assigned
INFORMATION
Bulletin No.: 05-08-46-004C
Date: December 23, 2010
Subject: OnStar(R) Phone Number Concerns (Phone Number Incorrect/Assigned to Another
Vehicle/Phone) That Occur During Diagnosis of OnStar(R) System
Models:
2000-2011 GM Passenger Cars and Trucks Equipped with OnStar(R) (RPO UE1)
Supercede: This bulletin is being revised to update model years up to 2011. Please discard
Corporate Bulletin Number 05-08-46-004B (Section 08 - Body and Accessories).
During diagnosis of an OnStar(R) concern, the technician may be told that the OnStar(R) phone
number is incorrect or tied to another vehicle and/or phone of some kind. To resolve these
concerns, the Tech 2(R) with software version 22.005 (or higher), has the capability to change the
OnStar(R) phone number.
Service Procedure
1. With the Tech 2(R), build the vehicle to specifications within the Diagnostics area of the Tech
2(R). 2. For vehicles with physical-based diagnostics - under Body, go to the OnStar(R) section.
Then select the Special Functions menu.
For vehicles with functional-based diagnostics - under Body and Accessories, go to the Cellular
Communication section. Select Module Setup and then Vehicle Communication Interface Module.
3. Locate the Program Phone Number prompt and select it. The original phone number will be
displayed on the Tech 2(R) screen. 4. Contact the OnStar(R) team at the GM Technical Assistance
Center (TAC) to obtain a new phone number. 5. Highlight the digits of the phone number one at a
time and enter the new phone number using the number keys on the Tech 2(R). 6. Press the Soft
key at the base of the screen for Done once these numbers have been changed on the screen. 7.
Press the Soft key for Done again. The area code or new phone number has now been
programmed into the phone. 8. Cycle the ignition to Off and open the driver's door. 9. Press the
blue OnStar(R) button to make sure that a normal connection can be made to the OnStar(R) call
center. If applicable, make sure the
Hands-Free Calling (HFC) works properly by making a phone call.
10. If the system is working properly, fax or voicemail a case closing into the OnStar(R) team at
TAC with the results. Dealers in Canada should
submit case closing information through the GM infoNET.
Please follow this diagnostic process thoroughly and complete each step. If the condition exhibited
is resolved WITHOUT completing every step, the remaining steps do not need to be performed. If
the procedure above does not resolve the condition, you must contact TAC for further assistance.
This diagnostic approach was developed specifically for this condition and should not automatically
be used for other vehicles with similar symptoms.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
For vehicles repaired under warranty, use the table.
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Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 05-08-46-004C
> Dec > 10 > OnStar(R) - Number Incorrect/Incorrectly Assigned > Page 102
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-08-46-006C
> Jan > 08 > OnStar(R) - Incorrect GPS Position Reported During Call
Emergency Contact Module: Customer Interest OnStar(R) - Incorrect GPS Position Reported
During Call
Bulletin No.: 02-08-46-006C
Date: January 08, 2008
INFORMATION
Subject: Incorrect OnStar(R) Global Positioning System (GPS) Location Reported During
OnStar(R) Call
Models: 2000-2008 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R)
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
02-08-46-006B (Section 08 - Body and Accessories).
A small number of the above-mentioned vehicles may exhibit a condition in which the vehicle
reports an inaccurate location to the OnStar(R) Call Center. This condition can only be identified
via a button press to the OnStar(R) Call Center by the customer. Call Center personnel will be able
to identify this inaccurate location condition. Customers will then be notified through the mail by
OnStar(R) if their vehicle exhibits this condition. Once this condition has been identified OnStar(R)
will instruct the customer to return to the dealership to have this condition corrected.
It is not necessary to reconfigure the vehicle after the following procedure.
In order to correct this condition you must cycle power to the OnStar(R) system. This can be done
by either removing the fuses powering the OnStar(R) system or disconnecting the OnStar(R)
module (VCIM) from the vehicle. As a last resort you can disconnect the vehicle's battery.
The power needs to be removed from the system for approximately 15 minutes.
After completing this procedure the vehicle should be taken to an area with an unobstructed view of
the sky. The vehicle should be kept running for approximately 10 minutes to allow the vehicle to
reacquire the global positioning system (GPS). Then contact the OnStar(R) Call Center via the blue
OnStar(R) button and ask the advisor to verify the GPS position.
If the OnStar(R) advisor still has an inaccurate GPS location refer to the Navigation Systems and
Cellular Communications sub-sections in the Service Manual in order to diagnose and repair the
concern. If the normal diagnostics lead to module replacement you will need to contact Technical
Assistance (TAC) and choose the OnStar(R) prompt. GM OnStar(R) TAC will assist in the
diagnosis and if appropriate order a replacement part. Replacement parts are usually shipped out
within 24 hours and a pre-paid return package label will be included for returning the faulty part. By
returning the faulty part you will avoid a significant non-return core charge.
Warranty Information (excluding Saab US Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab US Models)
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Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-08-46-006C
> Jan > 08 > OnStar(R) - Incorrect GPS Position Reported During Call > Page 107
For vehicles repaired under warranty use, the table.
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-08-46-007C
> Nov > 07 > OnStar(R) - Loss of GPS Signal/Hands Free Issues
Emergency Contact Module: Customer Interest OnStar(R) - Loss of GPS Signal/Hands Free Issues
Bulletin No.: 02-08-46-007C
Date: November 19, 2007
INFORMATION
Subject: Information on OnStar(R) System - Possible Loss of GPS Signal, Hands-Free Calling
Minutes Expire Prematurely and/or Inability to Add Hands-Free Calling Minutes
Models: 2001-2008 GM Passenger Cars and Light Duty Trucks (Including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R) System (RPO UE1)
Supercede:
This bulletin is being revised to add the 2008 model year, warranty information and to provide GPS
signal recovery steps (under Dealer Action heading) to do PRIOR to determining if the VIU/VCIM
needs replacement. Please discard Corporate Bulletin Number 02-08-46-007B (Section 08 - Body
& Accessories).
If the vehicle currently has analog-upgradable OnStar(R) hardware, then the customer should be
made aware of the digital upgrade program per the latest version of Service Bulletin #
05-08-46-006. Any analog OnStar system that is not upgraded prior to the end of 2007 will be
deactivated due to the upcoming phase-out of the analog cellular network in the U.S. and Canada.
If the vehicle has recently been upgraded or has had a service replacement unit installed, this
bulletin may not be applicable.
Certain 2001-2008 model year vehicles equipped with OnStar(R) may exhibit a condition with the
Global Positioning System (GPS) that causes inaccuracies in the GPS clock. The GPS system is
internal to the OnStar(R) Vehicle Interface Unit (VIU) or the Vehicle Communication Interface
Module (VCIM). This inaccuracy can result in a symptom where the OnStar(R) Call Center is
unable to obtain an accurate GPS signal, hands-Free Calling minutes expire prematurely and/or
the inability to add Hands-Free calling minutes.
Customer Notification
OnStar(R) will notify the customer by mail with instructions to contact their dealership service
department.
Dealer Action
Not all vehicles will require VIU/VCIM replacement.
The GPS signal in some vehicles may be recoverable. To determine if the signal is recoverable,
simply connect the Tech2(R) and using the GPS information data display option, observe the GPS
date and time. If the date/time stamps are equal to a date approximately 19 years in the future, the
GPS clock has exceeded its capacity and the VIU/VCIM will need to be replaced. If the date/time
stamp is in the past or near future, the GPS clock has simply generated an inaccurate value and
may be recoverable by performing the following power-up reset.
To initiate a power-up reset, battery voltage (batt. +) must be removed from the VIU/VCIM. The
preferred methods, in order, of initiating the reset are outlined below.
Remove the fuse that supplies Battery positive (Batt. +) voltage to the module (refer to the
applicable Service Information schematics for the appropriate fuse).
The next preferred method is to remove the connector to the OnStar(R) unit that Batt + is
contained.
The least preferable method is to remove the negative terminal of the vehicle battery. This will not
only initiate the power-up reset, but it may also result in the loss of radio presets and other stored
personalization information/settings in other modules as well.
After initiating the power-up reset, the GPS data will be set to the defaulted date and time and will
require an acquisition of the GPS signal in order to gain the proper date and time.
Acquiring the GPS signal requires running the vehicle in an open/unobstructed view of the sky.
First, contact OnStar(R) Technical Support by pressing the blue button. Allow the OnStar(R)
Technical Advisor to activate the GPS recovery process. This should take approximately 10
minutes. Continue to
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monitor the Tech2(R) for the current time and date. REMINDER - Keep in mind that the time
displayed on the Tech2(R) is in Greenwich Mean Time (GMT) and the offset is based on the time
zones relationship to GMT.
If replacement of the VIU/VCIM is necessary, you MUST reconfigure the OnStar® system. Failure
to reconfigure the system will result in an additional customer visit for repair. OnStar® VIU,
Generations 2 and 3, will require the technician to press the blue OnStar® button to reconfigure the
vehicle with an OnStar® advisor.
OnStar(R) VCIM, Generations 4-7 will require the technician to reconfigure the vehicle with the use
of the TIS2WEB and SPS applications (pass thru only), along with the Tech2(R).
The configuration and set-up procedure is a two-step process that must be completed step-by-step
without interruption or delay in between each step. This procedure enables an automated activation
without a button press by the technician to the OnStar(R) Call Center. Following this procedure, it
may take up to 24 hours for all OnStar(R) services to be fully activated.
How to Order Parts
If the OnStar(R) GPS date/time stamp is non-recoverable and the unit needs to be replaced,
dealers in the U.S. should contact Autocraft Electronics select the catalog item that contains this
bulletin number. Canadian dealers should contact MASS Electronics.
Dealers DO NOT need to call the GM Technical Assistance Center (TAC) for replacement
approval. Autocraft Electronics and MASS Electronics will be responsible for verifying that the
subject vehicle is a candidate for a replacement VIU/VCIM.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab U.S. Models)
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Emergency Contact Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-08-46-007C
> Nov > 07 > OnStar(R) - Loss of GPS Signal/Hands Free Issues > Page 113
For vehicles repaired under warranty, use the table.
Disclaimer
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Emergency Contact Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins for
Emergency Contact Module: > 05-08-46-004C > Dec > 10 > OnStar(R) - Number Incorrect/Incorrectly Assigned
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Number
Incorrect/Incorrectly Assigned
INFORMATION
Bulletin No.: 05-08-46-004C
Date: December 23, 2010
Subject: OnStar(R) Phone Number Concerns (Phone Number Incorrect/Assigned to Another
Vehicle/Phone) That Occur During Diagnosis of OnStar(R) System
Models:
2000-2011 GM Passenger Cars and Trucks Equipped with OnStar(R) (RPO UE1)
Supercede: This bulletin is being revised to update model years up to 2011. Please discard
Corporate Bulletin Number 05-08-46-004B (Section 08 - Body and Accessories).
During diagnosis of an OnStar(R) concern, the technician may be told that the OnStar(R) phone
number is incorrect or tied to another vehicle and/or phone of some kind. To resolve these
concerns, the Tech 2(R) with software version 22.005 (or higher), has the capability to change the
OnStar(R) phone number.
Service Procedure
1. With the Tech 2(R), build the vehicle to specifications within the Diagnostics area of the Tech
2(R). 2. For vehicles with physical-based diagnostics - under Body, go to the OnStar(R) section.
Then select the Special Functions menu.
For vehicles with functional-based diagnostics - under Body and Accessories, go to the Cellular
Communication section. Select Module Setup and then Vehicle Communication Interface Module.
3. Locate the Program Phone Number prompt and select it. The original phone number will be
displayed on the Tech 2(R) screen. 4. Contact the OnStar(R) team at the GM Technical Assistance
Center (TAC) to obtain a new phone number. 5. Highlight the digits of the phone number one at a
time and enter the new phone number using the number keys on the Tech 2(R). 6. Press the Soft
key at the base of the screen for Done once these numbers have been changed on the screen. 7.
Press the Soft key for Done again. The area code or new phone number has now been
programmed into the phone. 8. Cycle the ignition to Off and open the driver's door. 9. Press the
blue OnStar(R) button to make sure that a normal connection can be made to the OnStar(R) call
center. If applicable, make sure the
Hands-Free Calling (HFC) works properly by making a phone call.
10. If the system is working properly, fax or voicemail a case closing into the OnStar(R) team at
TAC with the results. Dealers in Canada should
submit case closing information through the GM infoNET.
Please follow this diagnostic process thoroughly and complete each step. If the condition exhibited
is resolved WITHOUT completing every step, the remaining steps do not need to be performed. If
the procedure above does not resolve the condition, you must contact TAC for further assistance.
This diagnostic approach was developed specifically for this condition and should not automatically
be used for other vehicles with similar symptoms.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
For vehicles repaired under warranty, use the table.
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Emergency Contact Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins for
Emergency Contact Module: > 05-08-46-004C > Dec > 10 > OnStar(R) - Number Incorrect/Incorrectly Assigned > Page 119
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Emergency Contact Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins for
Emergency Contact Module: > 02-08-44-007D > May > 09 > OnStar(R) - Negative Impact of Cloth/Vinyl Roofs
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Negative Impact of
Cloth/Vinyl Roofs
INFORMATION
Bulletin No.: 02-08-44-007D
Date: May 12, 2009
Subject: Negative Impact of Dealer-Installed Cloth/Vinyl Roofs on XM Radio and/or OnStar(R)
Systems
Models:
2002-2009 Passenger Cars and Trucks (Including Saturn) 2003-2009 HUMMER H2 2006-2009
HUMMER H3 2005-2009 Saab 9-7X with XM Radio (RPO U2K) and/or OnStar(R) (RPO UE1)
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
include the 2009 model year. Please discard Corporate Bulletin Number 02-08-44-007C (Section
08 - Body and Accessories).
..............................................................................................................................................................
..................................................................................
Dealers should not install a cloth or vinyl roof on vehicles that have been ordered with the XM radio
option (RPO U2K) and/or OnStar(R) (RPO UE1). The performance of these systems may be
negatively impacted by the installation of the cloth/vinyl roof. Additionally, water leaks may result
from installing a cloth or vinyl roof on vehicles with roof-mounted antenna systems. Relocating the
antenna to another spot on the vehicle exterior, in order to install a cloth or vinyl roof, is not advised
either. The performance of the OnStar(R) and XM Radio antennas has been optimized for their
current locations. Relocating the antennas may result in a performance degradation.
Disclaimer
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Technical Service Bulletin # 08089C Date: 081118
Campaign - Deactivation Of Analog OnStar(R)
# 08089C: Special Coverage Adjustment - Analog OnStar Deactivation (Nov 18, 2008)
Subject: 08089C -- SPECIAL COVERAGE ADJUSTMENT - ANALOG ONSTAR(R)
DEACTIVATION
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Models
The service procedure in this bulletin has been revised. Step 11 in the procedure for the 2004-2005
Saab 9-3 (9440) Convertible has been revised. Discard all copies of bulletin 08089B, issued
September 2008.
Condition
In November 2002, the U.S. Federal Commissions (FCC) ruled that wireless carriers would no
longer be required to support the analog wireless network beginning in 2008. As a result, On
Star(R) is unable to continue analog service.
OnStar(R) has deactivated most of the systems operating in the analog mode; however, there are
some vehicles that OnStar(R) could not deactivate. Although the analog OnStar(R) hardware in
these vehicles can no longer communicate with OnStar(R), the hardware in the vehicle is still
active. If the OnStar(R) emergency button is pressed, or in the case of an airbag deployment, or
near deployment, the customer may hear a recording that OnStar(R) is being contacted. However,
since analog service is no longer available, the call will not connect to OnStar(R). To end the call,
the customer must press the white phone or white dot button. If the call is not ended, the system
will continue to try to connect to OnStar(R) until the vehicle battery is drained.
Special Policy Adjustment
At the customer's request, dealers/retailers are to deactivate the OnStar(R) system. The service
will be made at no charge to the customer.
This special coverage covers the condition described above until December 31, 2008 for all
non-Saab vehicles; April 30, 2009 for all Saab vehicles.
Vehicles Involved
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Involved are certain vehicles within the VIN breakpoints shown above.
PARTS INFORMATION -- Saab US Only
Customer Notification
General Motors will notify customers of this special coverage on their vehicles (see copy of typical
customer letter shown in this bulletin - actual divisional letter may vary slightly).
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Claim Information - GM, Saturn Canada and Saab Canada Only
Claim Information - Saturn US Only
Customer Reimbursement Claims - Special Attention Required
Customer reimbursement claims must have entered into the "technician comments" field the CSO
# (if repair was completed at a Saturn Retail Facility) date, mileage, customer name, and any
deductibles and taxes paid by the customer.
Claim Information - Saab US Only
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1. To receive credit, submit a claim with the information above.
Disclaimer
2001 and Older Model Year Vehicles (Except Saab Vehicles)
2001 and Older Model Year Vehicles (Except Saab Vehicles)
Important:
2001 and older model year vehicles require the removal of the battery power from the OnStar(R)
vehicle interface unit (VIU) to eliminate the possibility of an inadvertent OnStar(R) or
emergency/airbag call.
1. Locate and gain access to the OnStar® VIU. Refer to OnStar Vehicle Interface Unit
Replacement in SI.
Important:
Complete removal of the VIU is usually not required. Perform only the steps required to gain
access to the C2 32-way blue connector. Residing in the C2 connector are the battery positive (+)
circuits. Removal of the C2 connector will deactivate the unit and eliminate the possibility of an
inadvertent OnStar(R) or emergency/airbag call.
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2. Disconnect the C2 32-way blue connector from the VIU and tape the connector to a secure
location. Refer to Cellular Communications Connector End Views and related schematics in SI, if
required.
Important:
DO NOT perform the OnStar(R) reconfiguration and/or programming procedure.
3. Secure the VIU in its original brackets and/or mounting locations and reinstall the VIU and
interior components that were removed to gain access to the VIU. Refer to OnStar Vehicle
Interface Unit Replacement in SI.
2002 Through 2006 Model Year Vehicles (Except Saab Vehicles)
2002 through 2006 Model Year Vehicles (Except Saab Vehicles)
Important:
The Tech 2 diagnostic tool must be updated with version 28.002 or later in order to successfully
perform the VCIM setup procedure and disable the analog system.
1. Connect the Tech 2 to the data link connector (DLC), which is located under the instrument
panel of the vehicle.
2. Turn the Tech 2 ON by pressing the power button.
Important:
Tech 2 screen navigation to get to the setup procedure depends on the year and make of the
vehicle. The actual name of the setup procedure (Setup New OnStar or VCIM Setup) depends on
model year and vehicle make as well. Example Tech 2 navigation to the setup procedure Tech 2
screen is provided below.
^ Diagnostics >> (2) 2002 >> Passenger Car >> Body >> C >> OnStar >> Special Functions >>
Setup New OnStar >>
^ Diagnostics >> (5) 2005 >> Passenger Car >> (4) Buick >> C >> Body >> Vehicle Comm.
Interface Module >> Module Setup >> VCIM Setup >>
3. Setup VCIM using the Tech 2. Follow on-screen instructions when you have reached the setup
Tech 2 screen.
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
1. Remove the ground cable from the battery's negative terminal.
2. Apply the handbrake brake.
3. Detach the floor console.
4. Remove the switch and the floor console:
3.1. Twist loose the immobilizer unit (A), bayonet fitting. Unplug the unit's connector.
3.2. Remove the ignition switch cover (B) by first undoing the rear edge of the cover and then
unhooking the front edge. Unplug the ignition
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switch lighting connector.
3.3. Undo the floor console's retaining bolts (C).
3.4. Take out the rear ashtray/cover (D).
3.5. Remove the screw (E) for the rear cover.
3.6. Remove the floor console's retaining nuts (E).
3.7. Detach the floor console (G) by pulling it straight back and lifting it slightly.
3.8. If required, detach the switch for the rear seat heater and unplug the connector.
4. Remove the switch and the floor console:
4.1. Detach the window lift module (A) by loosening it in the front edge (snap fastener). Unplug the
window lift module's connector.
4.2. Detach the switch for the roof lighting (B) and unplug its connector. Lift away the floor console.
5. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
5.1. Unplug the SRS control module's connector (A).
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5.2 Cut off the cable tie (B), detach the connector's rear end face (C) and pull out the connecting
rail (D).
5.3. Remove pin 39, cut off the cable terminal and insulate the end with tape (E). Fold back the
cable and secure it with tape (F).
5.4. Fit the connecting rail and end face.
5.5. Plug in the connector (A) and secure the cables with cable ties (B).
6. Install the floor console over the handbrake. Do not press the console down into place, but
instead allow it to fit loosely.
7. Install the switch:
7.1. Install the switch for the roof lighting (B) and plug in its connector.
7.2. Guide the connectors for the window lift module and rear seat heater, if equipped, through the
hole for each respective unit. Plug in the window lift module's connector and install the module (A).
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7.3. If equipped, connect the rear seat heater's connector and install the switch.
8. Install the floor console:
8.1. Install the floor console's retaining bolts (C) and retaining nuts (F).
8.2. Align the rear cover; make sure that the air duct connects firmly to the air nozzle. Screw in the
cover (E).
8.3. Install the ashtray/cover (D).
8.4. Install the ignition switch cover (B).
8.5. Plug in the immobilizer unit (A) connector. Install the unit, bayonet fitting.
9. Remove the OnStar(R) control modules and secure the wiring:
9.1. Remove the right-hand rear luggage compartment trim in accordance with WIS - 8.
Body - Interior equipment - Adjustment/Replacement.
9.2. Unplug the connectors (A) from the OnStar(R) control modules.
9.3. Remove the console (B) together with the OnStar(R) control modules.
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Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
9.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
9.5. Install the right-hand rear luggage compartment in accordance with WIS - 8. Body - Interior
equipment - Adjustment/Replacement.
10. Install the ground cable to the battery's negative terminal.
11. Clear the diagnostic trouble codes.
12. Set the date and time, see WIS - 3. Electrical system - Information display (SID_ - Technical
description.
2003-2005 Saab 9-3 (9400) 4D/5D; 2004-2005 Saab 9-3 (9400) CV
2003-2005 Saab 9-3 (9440) 4D/5D; 2004-2005 Saab 9-3 (9440) CV
Notice:
Handle the fiber optic cables with care or the signal may be distorted.
^ It is very important that the two leads in the connector are not confused with one another.
^ Do not splice the cables.
^ Do not bend the cable in a radius smaller than 25 mm (1 in).
^ Do not expose the cable to temperatures exceeding 185°F (85°C).
^ Keep the cable ends free from dirt and grime.
^ Do not expose the cable to impact as this may cause the transparent plastic to whiten, thereby
reducing the intensity of the light and causing possible communication interruptions.
^ The cable should not lie against any sharp edges as this may cause increased signal attenuation.
1. Remove the ECU CU with a Tech 2(R) according to the following: Fault diagnosis - Select model
year - Select Saab 9-3 Sport (9440) - All - Add/Remove - Control Module - CU/PU - Remove.
2. Remove the ground cable from the battery's negative terminal.
3. Remove the floor console in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
4. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
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4.1. Unplug the SRS control module's connector (A).
4.2. Cut off the cable tie (B), detach the connector's rear end face (C), and pull out the connecting
rail (D).
4.3. Extract pin 15, cut off the cable terminal and insulate the end with tape (E). Fold back the cable
and secure it with tape (F).
4.4. Fit the connecting rail and end face.
4.5. Plug in the connector (A) and secure the cables with cable ties (B).
5. Remove the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6. M03: Replace the optic cable on the right-hand side
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Important:
Secure the wiring harness so that there is no risk of chafing or rattling.
6.1. Remove the passenger seat in accordance with WIS 8. Body - Seats Adjustment/Replacement.
6.2. Remove the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.3. Remove the right-hand C pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.4. Fold the rear seat backrest forward.
6.5. Remove the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.6. Remove the A-pillar's lower side piece.
6.7. Open the cover on the right-hand wiring harness channels.
6.8. Loosen the locking strip (A) on the 2-pin connector (H2-11) for the optic cable, located by the
right-hand A-pillar.
6.9. Loosen the catch (B) and remove the optic cable that runs backward in the car.
6.10. Dismantle the end cap from the new optic cable (12 783 577) and connect it to the connector
H2-11. Push in the optic cable and make sure
the catch (B) locks and refit the locking strip (A).
6.11. Secure the connector and the old optic cable using the cable tie for the existing wiring
harness (C).
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.12. Place the optic cable in the wiring harness channels on the right-hand side. Thread through
the existing cable ties (C) if possible, otherwise,
secure with a cable tie to the existing one. Close the cover on the channels. Ensure the catches
lock.
6.13. Secure the optic cable along the right-hand rear wheel housing, next to the ordinary wiring
harness securing points and by the SRS unit (D).
6.14. Thread the optic cable up next to the safety belt by the old optic cable and place on the parcel
shelf.
6.15. Unplug the connectors (E) from the OnStar(R) control modules.
6.16. Remove the console (F) together with the OnStar(R) control modules.
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.17. Fold back the wiring harness and tape over the connectors (G). Fold back the wiring harness
once more and secure with cable ties (H).
6.18. Secure the new optic cable on the parcel shelf along the existing wiring harness by the
ordinary securing points and by the speaker (I).
6.19. Thread the optic cable down next to the old cable from the parcel shelf to the left-hand wheel
housing, next to REC. The cable is secured in
the existing clips.
6.20. Fit the right-hand C-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.21. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.22. Fit the passenger seat in accordance with WIS - 8. Body - Seats - Adjustment/Replacement.
6.23. Fit the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.24. Fold up the rear seat backrest.
6.25. Fit the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.26. Fit the A-pillar's lower side piece.
7. M04-05, 4D: Removing the OnStar® control modules and securing the wiring:
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7.1. Remove the console (A) together with the OnStar(R) control modules.
7.2. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
7.3. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
7.4. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
8. CV: Removing the OnStar(R) control modules and securing the wiring:
Adjustment/Replacement.
8.1. Open the luggage compartment floor.
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8.2. Remove the console (A) together with the OnStar(R) control modules.
8.3. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
8.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
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8.5. Close the luggage compartment floor.
9. Fold down the left-hand rear side hatch in the luggage compartment.
10. M03: Replace the optic cable on the left-hand rear side:
10.1. Place the optic cable so that it is positioned behind the terminal housing on top of REC (A).
10.2. Remove the locking strip (B) on the 2-pin connector (H2-9) for the optic cable.
10.3. Open the terminal housing (C) with a screwdriver. Remove the secondary catch (D) on the
connector and disconnect the optic cable coming
from the OnStar(R) control modules.
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10.4. Remove the end cap from the new optic cable, connect to the connector and refit the
secondary catch (D). Fit the terminal housing (C) to the
connector and refit the locking strip (B).
10.5. Secure the old optic cable together with the new one (E).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
11. CV: Remove the rear seat in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement. The O-bus connector H2-9 is located behind the left speaker.
12. M04-05: Disconnect the optic cables on the OnStar(R) control modules and join the cables:
12.1. Cut off the cable tie holding the connector (H2-9) against REC.
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12.2. Cars with brackets for e.g. an amplifier: Remove the pin strap (A) from the bracket and
remove the tape (B) holding the optic cables.
12.3. Remove the locking strip (C) on the 2-pin connector (H2-9). Open the terminal housing with a
screwdriver. Remove the secondary catch (E)
on the connector and remove the optic cables coming from the OnStar(R) control modules.
12.4. Loosen one of the optic cables remaining in H2-9 (F), connect it to the connector and fit the
secondary catch (E). Connect the connector so
that the optic cables are opposite each other (G). Connect the terminal housing (D) and refit the
locking strip (C).
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Emergency Contact Module: > 08089C > Nov > 08 > Campaign - Deactivation Of Analog OnStar(R) > Page 157
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.5. Cars with brackets for e.g. an amplifier: Fit the cable tie (11 900 515) to the wiring harness
approx. 100 mm (4 in) from H2-9, fit the cable
tie (H) to the bracket. Gather the optic cable in a gentle loop (I) and then place the loop behind the
bracket.
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.6. Cars without brackets for e.g. an amplifier: Gather the optic cable in a gentle loop (J) and
secure with cable tie.
13. CV: Fit the left-hand, rear side hatch trim in accordance with WIS - 8. Body - Interior equipment
- Adjustment/Replacement.
14. Fit the ground cable to the battery's negative terminal.
15. Carry out procedures after disconnecting the battery, see WIS - 3. Electrical System - Charging
system - Adjustment/Replacement.
Important:
Follow Tech 2(R) on-screen instructions.
16. Add ECU ICM, choose without OnStar(R). See WIS-General-Tech 2(R) - Description and
Operation - Add/Remove.
2000-2004 Saab 9-5
2000-2004 Saab 9-5
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1. Remove the ground cable from the battery's negative cable.
2. Remove the center console, see WIS - Body - Interior.
3. Loosen the gear shift housing (A).
AUT: Disconnect the 6-pin connector (B) to improve access to the gear shift housing screws.
4. Disconnect the signal cable from the SRS control module to the OnStar(R) control module and
secure the cable.
4.1. Disconnect the connector (A) from the SRS control module and cut the cable tie (B).
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4.2. Release the back end of the connector (C) and remove from the contact rail (D).
4.3. M00-01: Disconnect pin 39, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.4. M02-04: Disconnect pin 58, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.5. Assemble the contact rail and end.
4.6. Connect connector (A) and secure the cable using a cable tie (B).
5. Assemble the gear shift housing (A).
AUT: Connect connector (B).
6. Assemble the center console, see WIS - Body - Interior.
7. Remove the OnStar(R) control module and secure the cable harness:
7.1. 5D: Remove the right-hand cover from the luggage compartment floor.
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7.2. Remove the console (A).
7.3. Disconnect the connector (B) from the OnStar(R) control module.
Important:
Secure the cable harness to prevent the risk of scraping and rattling.
7.4. Fold back the cable harness and tape down the connector (C). Fold back the cable harness
again and secure with cable ties (D).
7.5. 5D: Assemble the right-hand cover for the luggage compartment floor.
8. Fit the ground cable on the battery's negative cable.
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9. Erase the diagnostic trouble codes.
10. Set the date and time, see WIS - 3. Electrical system - Information display (SID) - Technical
description.
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Emergency Contact Module: > 06-08-64-007A > Sep > 08 > OnStar(R) - Analog Only Systems Information
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Analog Only Systems
Information
INFORMATION
Bulletin No.: 06-08-64-007A
Date: September 22, 2008
Subject: Information on OnStar(R) Analog-Only Systems
Models
Supercede:
This bulletin is being revised to update the models affected list above. Please discard Corporate
Bulletin Number 06-08-46-007 (Section 08 - Body & Accessories).
All vehicles equipped with OnStar(R) listed in this bulletin were built with Analog-Only OnStar(R)
Hardware. OnStar(R) equipped vehicles with analog-only equipment were designed to operate only
on the analog wireless network and cannot be upgraded for digital network compatibility.
Vehicles with this equipment will no longer be able to receive OnStar(R) services beginning
January 1, 2008. At that time, service will be available only through Dual-Mode (Analog / Digital)
equipment. Analog-Only vehicles cannot be upgraded to digital equipment.
Disclaimer
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Emergency Contact Module: > 08-08-46-004 > Aug > 08 > OnStar(R) - Aftermarket Device Interference Information
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Aftermarket Device
Interference Information
INFORMATION
Bulletin No.: 08-08-46-004
Date: August 14, 2008
Subject: Information on Aftermarket Device Interference with OnStar(R) Diagnostic Services
Models: 2009 and Prior GM Passenger Car and Truck (including Saturn) 2009 and Prior HUMMER
H2, H3 Models 2009 and Prior Saab 9-7X
with OnStar(R) (RPO UE1)
This bulletin is being issued to provide dealer service personnel with information regarding
aftermarket devices connected to the Diagnostic Link Connector (DLC) and the impact to
OnStar(R) diagnostic probes and Vehicle Diagnostic e-mails.
Certain aftermarket devices, when connected to the Diagnostic Link Connector, such as, but not
limited to, Scan Tools, Trip Computers, Fuel Economy Analyzers and Insurance Tracking Devices,
interfere with OnStar's ability to perform a diagnostic probe when requested (via a blue button call)
by a subscriber. These devices also prohibit the ability to gather diagnostic and tire pressure data
for a subscriber's scheduled OnStar(R) Vehicle Diagnostic (OVD) e-mail.
These aftermarket devices utilize the Vehicles serial data bus to perform data requests and/or
information gathering. When these devices are requesting data, OnStar(R) is designed not to
interfere with any data request being made by these devices as required by OBD II regulations.
The OnStar(R) advisor is unable to definitively detect the presence of these devices and will only
be able to inform the caller or requester of the unsuccessful or incomplete probe and may in some
cases refer the subscriber/requester to take the vehicle to a dealer for diagnosis of the concern.
When performing a diagnostic check for an unsuccessful or incomplete OnStar(R) diagnostic
probe, or for concerns regarding completeness of the OnStar(R) Vehicle Diagnostic (OVD) e-mail,
verify that an aftermarket device was not present at the time of the requested probe. Regarding the
OVD e-mail, if an aftermarket device is interfering (including a Scan Tool of any type), the e-mail
will consistently display a "yellow" indication in diagnostics section for all vehicle systems except
the OnStar(R) System and Tire Pressure data (not available on all vehicles) will not be displayed
(i.e. section is collapsed). Successful diagnostic probes and complete OVD e-mails will resume
following the removal or disconnecting of the off-board device.
Disclaimer
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Emergency Contact Module: > 00-08-46-004C > Jan > 08 > OnStar(R) - Re-establishing OnStar(R) Communications
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Re-establishing OnStar(R)
Communications
Bulletin No.: 00-08-46-004C
Date: January 17, 2008
INFORMATION
Subject: Re-establishing Communications with OnStar(R) Center After Battery Disconnect
Models: 2000-2008 GM Passenger Cars and Trucks (Including Saturn and Saab)
with Digital OnStar(R) (RPO UE1)
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 00-08-46-004B (Section 08 - Body and Accessories).
When servicing any of the above models and a battery cable is disconnected or power to the
OnStar(R) Vehicle Communication Interface Module (VCIM) is interrupted for any reason the
following procedure must be performed to verify proper Global Positioning System (GPS) function.
Never swap OnStar(R) Vehicle Communication Interface Modules (VCIM) from other vehicles.
Transfer of OnStar(R) modules from other vehicles should not be done. Each OnStar(R) module
has a unique identification number. The VCIM has a specific Station Identification (STID). This
identification number is used by the National Cellular Telephone Network and OnStar(R) systems
and is stored in General Motors Vehicle History files by VIN.
After completing ALL repairs to the vehicle you must perform the following procedure:
Move the vehicle into an open area of the service lot.
Sit in the vehicle with the engine running and the radio turned on for five minutes.
Press the OnStar(R) button in the vehicle.
When the OnStar(R) advisor answers ask the advisor to verify the current location of the vehicle.
If the vehicle location is different than the location the OnStar(R) advisor gives contact GM
Technical Assistance (TAC) and choose the OnStar(R) prompt. GM OnStar(R) TAC will assist in
the diagnosis of a failed VCIM and, if appropriate, order a replacement part. Replacement parts are
usually shipped out within 24 hours, and a pre-paid return package label will be included for
returning the faulty part. By returning the faulty part, you will avoid a non-return core charge.
Disclaimer
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Emergency Contact Module: > 02-08-46-006C > Jan > 08 > OnStar(R) - Incorrect GPS Position Reported During Call
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Incorrect GPS Position
Reported During Call
Bulletin No.: 02-08-46-006C
Date: January 08, 2008
INFORMATION
Subject: Incorrect OnStar(R) Global Positioning System (GPS) Location Reported During
OnStar(R) Call
Models: 2000-2008 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R)
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
02-08-46-006B (Section 08 - Body and Accessories).
A small number of the above-mentioned vehicles may exhibit a condition in which the vehicle
reports an inaccurate location to the OnStar(R) Call Center. This condition can only be identified
via a button press to the OnStar(R) Call Center by the customer. Call Center personnel will be able
to identify this inaccurate location condition. Customers will then be notified through the mail by
OnStar(R) if their vehicle exhibits this condition. Once this condition has been identified OnStar(R)
will instruct the customer to return to the dealership to have this condition corrected.
It is not necessary to reconfigure the vehicle after the following procedure.
In order to correct this condition you must cycle power to the OnStar(R) system. This can be done
by either removing the fuses powering the OnStar(R) system or disconnecting the OnStar(R)
module (VCIM) from the vehicle. As a last resort you can disconnect the vehicle's battery.
The power needs to be removed from the system for approximately 15 minutes.
After completing this procedure the vehicle should be taken to an area with an unobstructed view of
the sky. The vehicle should be kept running for approximately 10 minutes to allow the vehicle to
reacquire the global positioning system (GPS). Then contact the OnStar(R) Call Center via the blue
OnStar(R) button and ask the advisor to verify the GPS position.
If the OnStar(R) advisor still has an inaccurate GPS location refer to the Navigation Systems and
Cellular Communications sub-sections in the Service Manual in order to diagnose and repair the
concern. If the normal diagnostics lead to module replacement you will need to contact Technical
Assistance (TAC) and choose the OnStar(R) prompt. GM OnStar(R) TAC will assist in the
diagnosis and if appropriate order a replacement part. Replacement parts are usually shipped out
within 24 hours and a pre-paid return package label will be included for returning the faulty part. By
returning the faulty part you will avoid a significant non-return core charge.
Warranty Information (excluding Saab US Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab US Models)
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Page 178
For vehicles repaired under warranty use, the table.
Disclaimer
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Emergency Contact Module: > 02-08-46-007C > Nov > 07 > OnStar(R) - Loss of GPS Signal/Hands Free Issues
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Loss of GPS Signal/Hands
Free Issues
Bulletin No.: 02-08-46-007C
Date: November 19, 2007
INFORMATION
Subject: Information on OnStar(R) System - Possible Loss of GPS Signal, Hands-Free Calling
Minutes Expire Prematurely and/or Inability to Add Hands-Free Calling Minutes
Models: 2001-2008 GM Passenger Cars and Light Duty Trucks (Including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R) System (RPO UE1)
Supercede:
This bulletin is being revised to add the 2008 model year, warranty information and to provide GPS
signal recovery steps (under Dealer Action heading) to do PRIOR to determining if the VIU/VCIM
needs replacement. Please discard Corporate Bulletin Number 02-08-46-007B (Section 08 - Body
& Accessories).
If the vehicle currently has analog-upgradable OnStar(R) hardware, then the customer should be
made aware of the digital upgrade program per the latest version of Service Bulletin #
05-08-46-006. Any analog OnStar system that is not upgraded prior to the end of 2007 will be
deactivated due to the upcoming phase-out of the analog cellular network in the U.S. and Canada.
If the vehicle has recently been upgraded or has had a service replacement unit installed, this
bulletin may not be applicable.
Certain 2001-2008 model year vehicles equipped with OnStar(R) may exhibit a condition with the
Global Positioning System (GPS) that causes inaccuracies in the GPS clock. The GPS system is
internal to the OnStar(R) Vehicle Interface Unit (VIU) or the Vehicle Communication Interface
Module (VCIM). This inaccuracy can result in a symptom where the OnStar(R) Call Center is
unable to obtain an accurate GPS signal, hands-Free Calling minutes expire prematurely and/or
the inability to add Hands-Free calling minutes.
Customer Notification
OnStar(R) will notify the customer by mail with instructions to contact their dealership service
department.
Dealer Action
Not all vehicles will require VIU/VCIM replacement.
The GPS signal in some vehicles may be recoverable. To determine if the signal is recoverable,
simply connect the Tech2(R) and using the GPS information data display option, observe the GPS
date and time. If the date/time stamps are equal to a date approximately 19 years in the future, the
GPS clock has exceeded its capacity and the VIU/VCIM will need to be replaced. If the date/time
stamp is in the past or near future, the GPS clock has simply generated an inaccurate value and
may be recoverable by performing the following power-up reset.
To initiate a power-up reset, battery voltage (batt. +) must be removed from the VIU/VCIM. The
preferred methods, in order, of initiating the reset are outlined below.
Remove the fuse that supplies Battery positive (Batt. +) voltage to the module (refer to the
applicable Service Information schematics for the appropriate fuse).
The next preferred method is to remove the connector to the OnStar(R) unit that Batt + is
contained.
The least preferable method is to remove the negative terminal of the vehicle battery. This will not
only initiate the power-up reset, but it may also result in the loss of radio presets and other stored
personalization information/settings in other modules as well.
After initiating the power-up reset, the GPS data will be set to the defaulted date and time and will
require an acquisition of the GPS signal in order to gain the proper date and time.
Acquiring the GPS signal requires running the vehicle in an open/unobstructed view of the sky.
First, contact OnStar(R) Technical Support by pressing the blue button. Allow the OnStar(R)
Technical Advisor to activate the GPS recovery process. This should take approximately 10
minutes. Continue to
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183
monitor the Tech2(R) for the current time and date. REMINDER - Keep in mind that the time
displayed on the Tech2(R) is in Greenwich Mean Time (GMT) and the offset is based on the time
zones relationship to GMT.
If replacement of the VIU/VCIM is necessary, you MUST reconfigure the OnStar® system. Failure
to reconfigure the system will result in an additional customer visit for repair. OnStar® VIU,
Generations 2 and 3, will require the technician to press the blue OnStar® button to reconfigure the
vehicle with an OnStar® advisor.
OnStar(R) VCIM, Generations 4-7 will require the technician to reconfigure the vehicle with the use
of the TIS2WEB and SPS applications (pass thru only), along with the Tech2(R).
The configuration and set-up procedure is a two-step process that must be completed step-by-step
without interruption or delay in between each step. This procedure enables an automated activation
without a button press by the technician to the OnStar(R) Call Center. Following this procedure, it
may take up to 24 hours for all OnStar(R) services to be fully activated.
How to Order Parts
If the OnStar(R) GPS date/time stamp is non-recoverable and the unit needs to be replaced,
dealers in the U.S. should contact Autocraft Electronics select the catalog item that contains this
bulletin number. Canadian dealers should contact MASS Electronics.
Dealers DO NOT need to call the GM Technical Assistance Center (TAC) for replacement
approval. Autocraft Electronics and MASS Electronics will be responsible for verifying that the
subject vehicle is a candidate for a replacement VIU/VCIM.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab U.S. Models)
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184
For vehicles repaired under warranty, use the table.
Disclaimer
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Emergency Contact Module: > 06-08-46-007 > Dec > 06 > OnStar - Analog-Only Systems Information
Emergency Contact Module: All Technical Service Bulletins OnStar - Analog-Only Systems
Information
Bulletin No.: 06-08-46-007
Date: December 13, 2006
INFORMATION
Subject: Information on OnStar(R) Analog-Only Systems
Models: 1996-2001 GM Passenger Cars and Trucks
Plus: 2002 Buick LeSabre, Rendezvous 2002-2003 Buick Century, Regal 2002-2005 Buick Park
Avenue 2002 Cadillac Eldorado, Escalade Models 2002 Chevrolet Avalanche, Silverado,
Suburban, Tahoe, Venture 2002 GMC Denali, Denali XL, Jimmy, Sierra, Yukon, Yukon XL 2002
Oldsmobile Intrigue, Silhouette 2002-2003 Oldsmobile Aurora 2002 Pontiac Aztek, Bonneville,
Montana 2002-2003 Pontiac Grand Prix
with OnStar(R) (RPO UE1)
All vehicles equipped with OnStar(R) listed in this bulletin were built with Analog-Only OnStar(R)
Hardware. OnStar(R) equipped vehicles with analog-only equipment were designed to operate only
on the analog wireless network and cannot be upgraded for digital network compatibility.
Vehicles with this equipment will no longer be able to receive OnStar(R) services beginning
January 1, 2008. At that time, service will be available only through Dual-Mode (Analog/Digital)
equipment. Analog-Only vehicles cannot be upgraded to digital equipment.
Disclaimer
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Emergency Contact Module: > 05-08-46-004C > Dec > 10 > OnStar(R) - Number Incorrect/Incorrectly Assigned
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Number
Incorrect/Incorrectly Assigned
INFORMATION
Bulletin No.: 05-08-46-004C
Date: December 23, 2010
Subject: OnStar(R) Phone Number Concerns (Phone Number Incorrect/Assigned to Another
Vehicle/Phone) That Occur During Diagnosis of OnStar(R) System
Models:
2000-2011 GM Passenger Cars and Trucks Equipped with OnStar(R) (RPO UE1)
Supercede: This bulletin is being revised to update model years up to 2011. Please discard
Corporate Bulletin Number 05-08-46-004B (Section 08 - Body and Accessories).
During diagnosis of an OnStar(R) concern, the technician may be told that the OnStar(R) phone
number is incorrect or tied to another vehicle and/or phone of some kind. To resolve these
concerns, the Tech 2(R) with software version 22.005 (or higher), has the capability to change the
OnStar(R) phone number.
Service Procedure
1. With the Tech 2(R), build the vehicle to specifications within the Diagnostics area of the Tech
2(R). 2. For vehicles with physical-based diagnostics - under Body, go to the OnStar(R) section.
Then select the Special Functions menu.
For vehicles with functional-based diagnostics - under Body and Accessories, go to the Cellular
Communication section. Select Module Setup and then Vehicle Communication Interface Module.
3. Locate the Program Phone Number prompt and select it. The original phone number will be
displayed on the Tech 2(R) screen. 4. Contact the OnStar(R) team at the GM Technical Assistance
Center (TAC) to obtain a new phone number. 5. Highlight the digits of the phone number one at a
time and enter the new phone number using the number keys on the Tech 2(R). 6. Press the Soft
key at the base of the screen for Done once these numbers have been changed on the screen. 7.
Press the Soft key for Done again. The area code or new phone number has now been
programmed into the phone. 8. Cycle the ignition to Off and open the driver's door. 9. Press the
blue OnStar(R) button to make sure that a normal connection can be made to the OnStar(R) call
center. If applicable, make sure the
Hands-Free Calling (HFC) works properly by making a phone call.
10. If the system is working properly, fax or voicemail a case closing into the OnStar(R) team at
TAC with the results. Dealers in Canada should
submit case closing information through the GM infoNET.
Please follow this diagnostic process thoroughly and complete each step. If the condition exhibited
is resolved WITHOUT completing every step, the remaining steps do not need to be performed. If
the procedure above does not resolve the condition, you must contact TAC for further assistance.
This diagnostic approach was developed specifically for this condition and should not automatically
be used for other vehicles with similar symptoms.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
For vehicles repaired under warranty, use the table.
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Emergency Contact Module: > 02-08-44-007D > May > 09 > OnStar(R) - Negative Impact of Cloth/Vinyl Roofs
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Negative Impact of
Cloth/Vinyl Roofs
INFORMATION
Bulletin No.: 02-08-44-007D
Date: May 12, 2009
Subject: Negative Impact of Dealer-Installed Cloth/Vinyl Roofs on XM Radio and/or OnStar(R)
Systems
Models:
2002-2009 Passenger Cars and Trucks (Including Saturn) 2003-2009 HUMMER H2 2006-2009
HUMMER H3 2005-2009 Saab 9-7X with XM Radio (RPO U2K) and/or OnStar(R) (RPO UE1)
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
include the 2009 model year. Please discard Corporate Bulletin Number 02-08-44-007C (Section
08 - Body and Accessories).
..............................................................................................................................................................
..................................................................................
Dealers should not install a cloth or vinyl roof on vehicles that have been ordered with the XM radio
option (RPO U2K) and/or OnStar(R) (RPO UE1). The performance of these systems may be
negatively impacted by the installation of the cloth/vinyl roof. Additionally, water leaks may result
from installing a cloth or vinyl roof on vehicles with roof-mounted antenna systems. Relocating the
antenna to another spot on the vehicle exterior, in order to install a cloth or vinyl roof, is not advised
either. The performance of the OnStar(R) and XM Radio antennas has been optimized for their
current locations. Relocating the antennas may result in a performance degradation.
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Emergency Contact Module: > 06-08-64-007A > Sep > 08 > OnStar(R) - Analog Only Systems Information
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Analog Only Systems
Information
INFORMATION
Bulletin No.: 06-08-64-007A
Date: September 22, 2008
Subject: Information on OnStar(R) Analog-Only Systems
Models
Supercede:
This bulletin is being revised to update the models affected list above. Please discard Corporate
Bulletin Number 06-08-46-007 (Section 08 - Body & Accessories).
All vehicles equipped with OnStar(R) listed in this bulletin were built with Analog-Only OnStar(R)
Hardware. OnStar(R) equipped vehicles with analog-only equipment were designed to operate only
on the analog wireless network and cannot be upgraded for digital network compatibility.
Vehicles with this equipment will no longer be able to receive OnStar(R) services beginning
January 1, 2008. At that time, service will be available only through Dual-Mode (Analog / Digital)
equipment. Analog-Only vehicles cannot be upgraded to digital equipment.
Disclaimer
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Emergency Contact Module: > 08-08-46-004 > Aug > 08 > OnStar(R) - Aftermarket Device Interference Information
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Aftermarket Device
Interference Information
INFORMATION
Bulletin No.: 08-08-46-004
Date: August 14, 2008
Subject: Information on Aftermarket Device Interference with OnStar(R) Diagnostic Services
Models: 2009 and Prior GM Passenger Car and Truck (including Saturn) 2009 and Prior HUMMER
H2, H3 Models 2009 and Prior Saab 9-7X
with OnStar(R) (RPO UE1)
This bulletin is being issued to provide dealer service personnel with information regarding
aftermarket devices connected to the Diagnostic Link Connector (DLC) and the impact to
OnStar(R) diagnostic probes and Vehicle Diagnostic e-mails.
Certain aftermarket devices, when connected to the Diagnostic Link Connector, such as, but not
limited to, Scan Tools, Trip Computers, Fuel Economy Analyzers and Insurance Tracking Devices,
interfere with OnStar's ability to perform a diagnostic probe when requested (via a blue button call)
by a subscriber. These devices also prohibit the ability to gather diagnostic and tire pressure data
for a subscriber's scheduled OnStar(R) Vehicle Diagnostic (OVD) e-mail.
These aftermarket devices utilize the Vehicles serial data bus to perform data requests and/or
information gathering. When these devices are requesting data, OnStar(R) is designed not to
interfere with any data request being made by these devices as required by OBD II regulations.
The OnStar(R) advisor is unable to definitively detect the presence of these devices and will only
be able to inform the caller or requester of the unsuccessful or incomplete probe and may in some
cases refer the subscriber/requester to take the vehicle to a dealer for diagnosis of the concern.
When performing a diagnostic check for an unsuccessful or incomplete OnStar(R) diagnostic
probe, or for concerns regarding completeness of the OnStar(R) Vehicle Diagnostic (OVD) e-mail,
verify that an aftermarket device was not present at the time of the requested probe. Regarding the
OVD e-mail, if an aftermarket device is interfering (including a Scan Tool of any type), the e-mail
will consistently display a "yellow" indication in diagnostics section for all vehicle systems except
the OnStar(R) System and Tire Pressure data (not available on all vehicles) will not be displayed
(i.e. section is collapsed). Successful diagnostic probes and complete OVD e-mails will resume
following the removal or disconnecting of the off-board device.
Disclaimer
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Emergency Contact Module: > 00-08-46-004C > Jan > 08 > OnStar(R) - Re-establishing OnStar(R) Communications
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Re-establishing OnStar(R)
Communications
Bulletin No.: 00-08-46-004C
Date: January 17, 2008
INFORMATION
Subject: Re-establishing Communications with OnStar(R) Center After Battery Disconnect
Models: 2000-2008 GM Passenger Cars and Trucks (Including Saturn and Saab)
with Digital OnStar(R) (RPO UE1)
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 00-08-46-004B (Section 08 - Body and Accessories).
When servicing any of the above models and a battery cable is disconnected or power to the
OnStar(R) Vehicle Communication Interface Module (VCIM) is interrupted for any reason the
following procedure must be performed to verify proper Global Positioning System (GPS) function.
Never swap OnStar(R) Vehicle Communication Interface Modules (VCIM) from other vehicles.
Transfer of OnStar(R) modules from other vehicles should not be done. Each OnStar(R) module
has a unique identification number. The VCIM has a specific Station Identification (STID). This
identification number is used by the National Cellular Telephone Network and OnStar(R) systems
and is stored in General Motors Vehicle History files by VIN.
After completing ALL repairs to the vehicle you must perform the following procedure:
Move the vehicle into an open area of the service lot.
Sit in the vehicle with the engine running and the radio turned on for five minutes.
Press the OnStar(R) button in the vehicle.
When the OnStar(R) advisor answers ask the advisor to verify the current location of the vehicle.
If the vehicle location is different than the location the OnStar(R) advisor gives contact GM
Technical Assistance (TAC) and choose the OnStar(R) prompt. GM OnStar(R) TAC will assist in
the diagnosis of a failed VCIM and, if appropriate, order a replacement part. Replacement parts are
usually shipped out within 24 hours, and a pre-paid return package label will be included for
returning the faulty part. By returning the faulty part, you will avoid a non-return core charge.
Disclaimer
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Emergency Contact Module: > 02-08-46-006C > Jan > 08 > OnStar(R) - Incorrect GPS Position Reported During Call
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Incorrect GPS Position
Reported During Call
Bulletin No.: 02-08-46-006C
Date: January 08, 2008
INFORMATION
Subject: Incorrect OnStar(R) Global Positioning System (GPS) Location Reported During
OnStar(R) Call
Models: 2000-2008 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R)
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
02-08-46-006B (Section 08 - Body and Accessories).
A small number of the above-mentioned vehicles may exhibit a condition in which the vehicle
reports an inaccurate location to the OnStar(R) Call Center. This condition can only be identified
via a button press to the OnStar(R) Call Center by the customer. Call Center personnel will be able
to identify this inaccurate location condition. Customers will then be notified through the mail by
OnStar(R) if their vehicle exhibits this condition. Once this condition has been identified OnStar(R)
will instruct the customer to return to the dealership to have this condition corrected.
It is not necessary to reconfigure the vehicle after the following procedure.
In order to correct this condition you must cycle power to the OnStar(R) system. This can be done
by either removing the fuses powering the OnStar(R) system or disconnecting the OnStar(R)
module (VCIM) from the vehicle. As a last resort you can disconnect the vehicle's battery.
The power needs to be removed from the system for approximately 15 minutes.
After completing this procedure the vehicle should be taken to an area with an unobstructed view of
the sky. The vehicle should be kept running for approximately 10 minutes to allow the vehicle to
reacquire the global positioning system (GPS). Then contact the OnStar(R) Call Center via the blue
OnStar(R) button and ask the advisor to verify the GPS position.
If the OnStar(R) advisor still has an inaccurate GPS location refer to the Navigation Systems and
Cellular Communications sub-sections in the Service Manual in order to diagnose and repair the
concern. If the normal diagnostics lead to module replacement you will need to contact Technical
Assistance (TAC) and choose the OnStar(R) prompt. GM OnStar(R) TAC will assist in the
diagnosis and if appropriate order a replacement part. Replacement parts are usually shipped out
within 24 hours and a pre-paid return package label will be included for returning the faulty part. By
returning the faulty part you will avoid a significant non-return core charge.
Warranty Information (excluding Saab US Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab US Models)
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Page 215
For vehicles repaired under warranty use, the table.
Disclaimer
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Emergency Contact Module: > 02-08-46-007C > Nov > 07 > OnStar(R) - Loss of GPS Signal/Hands Free Issues
Emergency Contact Module: All Technical Service Bulletins OnStar(R) - Loss of GPS Signal/Hands
Free Issues
Bulletin No.: 02-08-46-007C
Date: November 19, 2007
INFORMATION
Subject: Information on OnStar(R) System - Possible Loss of GPS Signal, Hands-Free Calling
Minutes Expire Prematurely and/or Inability to Add Hands-Free Calling Minutes
Models: 2001-2008 GM Passenger Cars and Light Duty Trucks (Including Saturn) 2003-2008
HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
with OnStar(R) System (RPO UE1)
Supercede:
This bulletin is being revised to add the 2008 model year, warranty information and to provide GPS
signal recovery steps (under Dealer Action heading) to do PRIOR to determining if the VIU/VCIM
needs replacement. Please discard Corporate Bulletin Number 02-08-46-007B (Section 08 - Body
& Accessories).
If the vehicle currently has analog-upgradable OnStar(R) hardware, then the customer should be
made aware of the digital upgrade program per the latest version of Service Bulletin #
05-08-46-006. Any analog OnStar system that is not upgraded prior to the end of 2007 will be
deactivated due to the upcoming phase-out of the analog cellular network in the U.S. and Canada.
If the vehicle has recently been upgraded or has had a service replacement unit installed, this
bulletin may not be applicable.
Certain 2001-2008 model year vehicles equipped with OnStar(R) may exhibit a condition with the
Global Positioning System (GPS) that causes inaccuracies in the GPS clock. The GPS system is
internal to the OnStar(R) Vehicle Interface Unit (VIU) or the Vehicle Communication Interface
Module (VCIM). This inaccuracy can result in a symptom where the OnStar(R) Call Center is
unable to obtain an accurate GPS signal, hands-Free Calling minutes expire prematurely and/or
the inability to add Hands-Free calling minutes.
Customer Notification
OnStar(R) will notify the customer by mail with instructions to contact their dealership service
department.
Dealer Action
Not all vehicles will require VIU/VCIM replacement.
The GPS signal in some vehicles may be recoverable. To determine if the signal is recoverable,
simply connect the Tech2(R) and using the GPS information data display option, observe the GPS
date and time. If the date/time stamps are equal to a date approximately 19 years in the future, the
GPS clock has exceeded its capacity and the VIU/VCIM will need to be replaced. If the date/time
stamp is in the past or near future, the GPS clock has simply generated an inaccurate value and
may be recoverable by performing the following power-up reset.
To initiate a power-up reset, battery voltage (batt. +) must be removed from the VIU/VCIM. The
preferred methods, in order, of initiating the reset are outlined below.
Remove the fuse that supplies Battery positive (Batt. +) voltage to the module (refer to the
applicable Service Information schematics for the appropriate fuse).
The next preferred method is to remove the connector to the OnStar(R) unit that Batt + is
contained.
The least preferable method is to remove the negative terminal of the vehicle battery. This will not
only initiate the power-up reset, but it may also result in the loss of radio presets and other stored
personalization information/settings in other modules as well.
After initiating the power-up reset, the GPS data will be set to the defaulted date and time and will
require an acquisition of the GPS signal in order to gain the proper date and time.
Acquiring the GPS signal requires running the vehicle in an open/unobstructed view of the sky.
First, contact OnStar(R) Technical Support by pressing the blue button. Allow the OnStar(R)
Technical Advisor to activate the GPS recovery process. This should take approximately 10
minutes. Continue to
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monitor the Tech2(R) for the current time and date. REMINDER - Keep in mind that the time
displayed on the Tech2(R) is in Greenwich Mean Time (GMT) and the offset is based on the time
zones relationship to GMT.
If replacement of the VIU/VCIM is necessary, you MUST reconfigure the OnStar® system. Failure
to reconfigure the system will result in an additional customer visit for repair. OnStar® VIU,
Generations 2 and 3, will require the technician to press the blue OnStar® button to reconfigure the
vehicle with an OnStar® advisor.
OnStar(R) VCIM, Generations 4-7 will require the technician to reconfigure the vehicle with the use
of the TIS2WEB and SPS applications (pass thru only), along with the Tech2(R).
The configuration and set-up procedure is a two-step process that must be completed step-by-step
without interruption or delay in between each step. This procedure enables an automated activation
without a button press by the technician to the OnStar(R) Call Center. Following this procedure, it
may take up to 24 hours for all OnStar(R) services to be fully activated.
How to Order Parts
If the OnStar(R) GPS date/time stamp is non-recoverable and the unit needs to be replaced,
dealers in the U.S. should contact Autocraft Electronics select the catalog item that contains this
bulletin number. Canadian dealers should contact MASS Electronics.
Dealers DO NOT need to call the GM Technical Assistance Center (TAC) for replacement
approval. Autocraft Electronics and MASS Electronics will be responsible for verifying that the
subject vehicle is a candidate for a replacement VIU/VCIM.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab U.S. Models)
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For vehicles repaired under warranty, use the table.
Disclaimer
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Emergency Contact Module: > 06-08-46-007 > Dec > 06 > OnStar - Analog-Only Systems Information
Emergency Contact Module: All Technical Service Bulletins OnStar - Analog-Only Systems
Information
Bulletin No.: 06-08-46-007
Date: December 13, 2006
INFORMATION
Subject: Information on OnStar(R) Analog-Only Systems
Models: 1996-2001 GM Passenger Cars and Trucks
Plus: 2002 Buick LeSabre, Rendezvous 2002-2003 Buick Century, Regal 2002-2005 Buick Park
Avenue 2002 Cadillac Eldorado, Escalade Models 2002 Chevrolet Avalanche, Silverado,
Suburban, Tahoe, Venture 2002 GMC Denali, Denali XL, Jimmy, Sierra, Yukon, Yukon XL 2002
Oldsmobile Intrigue, Silhouette 2002-2003 Oldsmobile Aurora 2002 Pontiac Aztek, Bonneville,
Montana 2002-2003 Pontiac Grand Prix
with OnStar(R) (RPO UE1)
All vehicles equipped with OnStar(R) listed in this bulletin were built with Analog-Only OnStar(R)
Hardware. OnStar(R) equipped vehicles with analog-only equipment were designed to operate only
on the analog wireless network and cannot be upgraded for digital network compatibility.
Vehicles with this equipment will no longer be able to receive OnStar(R) services beginning
January 1, 2008. At that time, service will be available only through Dual-Mode (Analog/Digital)
equipment. Analog-Only vehicles cannot be upgraded to digital equipment.
Disclaimer
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Emergency Contact Module: > 08089C > Nov > 08 > Campaign - Deactivation Of Analog OnStar(R)
Technical Service Bulletin # 08089C Date: 081118
Campaign - Deactivation Of Analog OnStar(R)
# 08089C: Special Coverage Adjustment - Analog OnStar Deactivation (Nov 18, 2008)
Subject: 08089C -- SPECIAL COVERAGE ADJUSTMENT - ANALOG ONSTAR(R)
DEACTIVATION
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Models
The service procedure in this bulletin has been revised. Step 11 in the procedure for the 2004-2005
Saab 9-3 (9440) Convertible has been revised. Discard all copies of bulletin 08089B, issued
September 2008.
Condition
In November 2002, the U.S. Federal Commissions (FCC) ruled that wireless carriers would no
longer be required to support the analog wireless network beginning in 2008. As a result, On
Star(R) is unable to continue analog service.
OnStar(R) has deactivated most of the systems operating in the analog mode; however, there are
some vehicles that OnStar(R) could not deactivate. Although the analog OnStar(R) hardware in
these vehicles can no longer communicate with OnStar(R), the hardware in the vehicle is still
active. If the OnStar(R) emergency button is pressed, or in the case of an airbag deployment, or
near deployment, the customer may hear a recording that OnStar(R) is being contacted. However,
since analog service is no longer available, the call will not connect to OnStar(R). To end the call,
the customer must press the white phone or white dot button. If the call is not ended, the system
will continue to try to connect to OnStar(R) until the vehicle battery is drained.
Special Policy Adjustment
At the customer's request, dealers/retailers are to deactivate the OnStar(R) system. The service
will be made at no charge to the customer.
This special coverage covers the condition described above until December 31, 2008 for all
non-Saab vehicles; April 30, 2009 for all Saab vehicles.
Vehicles Involved
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Involved are certain vehicles within the VIN breakpoints shown above.
PARTS INFORMATION -- Saab US Only
Customer Notification
General Motors will notify customers of this special coverage on their vehicles (see copy of typical
customer letter shown in this bulletin - actual divisional letter may vary slightly).
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Claim Information - GM, Saturn Canada and Saab Canada Only
Claim Information - Saturn US Only
Customer Reimbursement Claims - Special Attention Required
Customer reimbursement claims must have entered into the "technician comments" field the CSO
# (if repair was completed at a Saturn Retail Facility) date, mileage, customer name, and any
deductibles and taxes paid by the customer.
Claim Information - Saab US Only
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1. To receive credit, submit a claim with the information above.
Disclaimer
2001 and Older Model Year Vehicles (Except Saab Vehicles)
2001 and Older Model Year Vehicles (Except Saab Vehicles)
Important:
2001 and older model year vehicles require the removal of the battery power from the OnStar(R)
vehicle interface unit (VIU) to eliminate the possibility of an inadvertent OnStar(R) or
emergency/airbag call.
1. Locate and gain access to the OnStar® VIU. Refer to OnStar Vehicle Interface Unit
Replacement in SI.
Important:
Complete removal of the VIU is usually not required. Perform only the steps required to gain
access to the C2 32-way blue connector. Residing in the C2 connector are the battery positive (+)
circuits. Removal of the C2 connector will deactivate the unit and eliminate the possibility of an
inadvertent OnStar(R) or emergency/airbag call.
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2. Disconnect the C2 32-way blue connector from the VIU and tape the connector to a secure
location. Refer to Cellular Communications Connector End Views and related schematics in SI, if
required.
Important:
DO NOT perform the OnStar(R) reconfiguration and/or programming procedure.
3. Secure the VIU in its original brackets and/or mounting locations and reinstall the VIU and
interior components that were removed to gain access to the VIU. Refer to OnStar Vehicle
Interface Unit Replacement in SI.
2002 Through 2006 Model Year Vehicles (Except Saab Vehicles)
2002 through 2006 Model Year Vehicles (Except Saab Vehicles)
Important:
The Tech 2 diagnostic tool must be updated with version 28.002 or later in order to successfully
perform the VCIM setup procedure and disable the analog system.
1. Connect the Tech 2 to the data link connector (DLC), which is located under the instrument
panel of the vehicle.
2. Turn the Tech 2 ON by pressing the power button.
Important:
Tech 2 screen navigation to get to the setup procedure depends on the year and make of the
vehicle. The actual name of the setup procedure (Setup New OnStar or VCIM Setup) depends on
model year and vehicle make as well. Example Tech 2 navigation to the setup procedure Tech 2
screen is provided below.
^ Diagnostics >> (2) 2002 >> Passenger Car >> Body >> C >> OnStar >> Special Functions >>
Setup New OnStar >>
^ Diagnostics >> (5) 2005 >> Passenger Car >> (4) Buick >> C >> Body >> Vehicle Comm.
Interface Module >> Module Setup >> VCIM Setup >>
3. Setup VCIM using the Tech 2. Follow on-screen instructions when you have reached the setup
Tech 2 screen.
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
2000-2002 Saab 9-3 (9400) 4D/5D; 2000-2003 Saab 9-3 (9400) CV
1. Remove the ground cable from the battery's negative terminal.
2. Apply the handbrake brake.
3. Detach the floor console.
4. Remove the switch and the floor console:
3.1. Twist loose the immobilizer unit (A), bayonet fitting. Unplug the unit's connector.
3.2. Remove the ignition switch cover (B) by first undoing the rear edge of the cover and then
unhooking the front edge. Unplug the ignition
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switch lighting connector.
3.3. Undo the floor console's retaining bolts (C).
3.4. Take out the rear ashtray/cover (D).
3.5. Remove the screw (E) for the rear cover.
3.6. Remove the floor console's retaining nuts (E).
3.7. Detach the floor console (G) by pulling it straight back and lifting it slightly.
3.8. If required, detach the switch for the rear seat heater and unplug the connector.
4. Remove the switch and the floor console:
4.1. Detach the window lift module (A) by loosening it in the front edge (snap fastener). Unplug the
window lift module's connector.
4.2. Detach the switch for the roof lighting (B) and unplug its connector. Lift away the floor console.
5. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
5.1. Unplug the SRS control module's connector (A).
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5.2 Cut off the cable tie (B), detach the connector's rear end face (C) and pull out the connecting
rail (D).
5.3. Remove pin 39, cut off the cable terminal and insulate the end with tape (E). Fold back the
cable and secure it with tape (F).
5.4. Fit the connecting rail and end face.
5.5. Plug in the connector (A) and secure the cables with cable ties (B).
6. Install the floor console over the handbrake. Do not press the console down into place, but
instead allow it to fit loosely.
7. Install the switch:
7.1. Install the switch for the roof lighting (B) and plug in its connector.
7.2. Guide the connectors for the window lift module and rear seat heater, if equipped, through the
hole for each respective unit. Plug in the window lift module's connector and install the module (A).
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7.3. If equipped, connect the rear seat heater's connector and install the switch.
8. Install the floor console:
8.1. Install the floor console's retaining bolts (C) and retaining nuts (F).
8.2. Align the rear cover; make sure that the air duct connects firmly to the air nozzle. Screw in the
cover (E).
8.3. Install the ashtray/cover (D).
8.4. Install the ignition switch cover (B).
8.5. Plug in the immobilizer unit (A) connector. Install the unit, bayonet fitting.
9. Remove the OnStar(R) control modules and secure the wiring:
9.1. Remove the right-hand rear luggage compartment trim in accordance with WIS - 8.
Body - Interior equipment - Adjustment/Replacement.
9.2. Unplug the connectors (A) from the OnStar(R) control modules.
9.3. Remove the console (B) together with the OnStar(R) control modules.
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Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
9.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
9.5. Install the right-hand rear luggage compartment in accordance with WIS - 8. Body - Interior
equipment - Adjustment/Replacement.
10. Install the ground cable to the battery's negative terminal.
11. Clear the diagnostic trouble codes.
12. Set the date and time, see WIS - 3. Electrical system - Information display (SID_ - Technical
description.
2003-2005 Saab 9-3 (9400) 4D/5D; 2004-2005 Saab 9-3 (9400) CV
2003-2005 Saab 9-3 (9440) 4D/5D; 2004-2005 Saab 9-3 (9440) CV
Notice:
Handle the fiber optic cables with care or the signal may be distorted.
^ It is very important that the two leads in the connector are not confused with one another.
^ Do not splice the cables.
^ Do not bend the cable in a radius smaller than 25 mm (1 in).
^ Do not expose the cable to temperatures exceeding 185°F (85°C).
^ Keep the cable ends free from dirt and grime.
^ Do not expose the cable to impact as this may cause the transparent plastic to whiten, thereby
reducing the intensity of the light and causing possible communication interruptions.
^ The cable should not lie against any sharp edges as this may cause increased signal attenuation.
1. Remove the ECU CU with a Tech 2(R) according to the following: Fault diagnosis - Select model
year - Select Saab 9-3 Sport (9440) - All - Add/Remove - Control Module - CU/PU - Remove.
2. Remove the ground cable from the battery's negative terminal.
3. Remove the floor console in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
4. Pry out the signal line from the SRS control module to the OnStar(R) control module and secure
it:
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4.1. Unplug the SRS control module's connector (A).
4.2. Cut off the cable tie (B), detach the connector's rear end face (C), and pull out the connecting
rail (D).
4.3. Extract pin 15, cut off the cable terminal and insulate the end with tape (E). Fold back the cable
and secure it with tape (F).
4.4. Fit the connecting rail and end face.
4.5. Plug in the connector (A) and secure the cables with cable ties (B).
5. Remove the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6. M03: Replace the optic cable on the right-hand side
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Important:
Secure the wiring harness so that there is no risk of chafing or rattling.
6.1. Remove the passenger seat in accordance with WIS 8. Body - Seats Adjustment/Replacement.
6.2. Remove the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.3. Remove the right-hand C pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.4. Fold the rear seat backrest forward.
6.5. Remove the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.6. Remove the A-pillar's lower side piece.
6.7. Open the cover on the right-hand wiring harness channels.
6.8. Loosen the locking strip (A) on the 2-pin connector (H2-11) for the optic cable, located by the
right-hand A-pillar.
6.9. Loosen the catch (B) and remove the optic cable that runs backward in the car.
6.10. Dismantle the end cap from the new optic cable (12 783 577) and connect it to the connector
H2-11. Push in the optic cable and make sure
the catch (B) locks and refit the locking strip (A).
6.11. Secure the connector and the old optic cable using the cable tie for the existing wiring
harness (C).
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.12. Place the optic cable in the wiring harness channels on the right-hand side. Thread through
the existing cable ties (C) if possible, otherwise,
secure with a cable tie to the existing one. Close the cover on the channels. Ensure the catches
lock.
6.13. Secure the optic cable along the right-hand rear wheel housing, next to the ordinary wiring
harness securing points and by the SRS unit (D).
6.14. Thread the optic cable up next to the safety belt by the old optic cable and place on the parcel
shelf.
6.15. Unplug the connectors (E) from the OnStar(R) control modules.
6.16. Remove the console (F) together with the OnStar(R) control modules.
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
6.17. Fold back the wiring harness and tape over the connectors (G). Fold back the wiring harness
once more and secure with cable ties (H).
6.18. Secure the new optic cable on the parcel shelf along the existing wiring harness by the
ordinary securing points and by the speaker (I).
6.19. Thread the optic cable down next to the old cable from the parcel shelf to the left-hand wheel
housing, next to REC. The cable is secured in
the existing clips.
6.20. Fit the right-hand C-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.21. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.22. Fit the passenger seat in accordance with WIS - 8. Body - Seats - Adjustment/Replacement.
6.23. Fit the right-hand side bolster in accordance with WIS - 8. Body - Seats Adjustment/Replacement.
6.24. Fold up the rear seat backrest.
6.25. Fit the right-hand B-pillar trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
6.26. Fit the A-pillar's lower side piece.
7. M04-05, 4D: Removing the OnStar® control modules and securing the wiring:
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7.1. Remove the console (A) together with the OnStar(R) control modules.
7.2. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
7.3. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
7.4. Fit the parcel shelf trim in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement.
8. CV: Removing the OnStar(R) control modules and securing the wiring:
Adjustment/Replacement.
8.1. Open the luggage compartment floor.
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8.2. Remove the console (A) together with the OnStar(R) control modules.
8.3. Remove the connectors (B).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
8.4. Fold back the wiring harness and tape over the connectors (C). Fold back the wiring harness
once more and secure with cable ties (D).
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8.5. Close the luggage compartment floor.
9. Fold down the left-hand rear side hatch in the luggage compartment.
10. M03: Replace the optic cable on the left-hand rear side:
10.1. Place the optic cable so that it is positioned behind the terminal housing on top of REC (A).
10.2. Remove the locking strip (B) on the 2-pin connector (H2-9) for the optic cable.
10.3. Open the terminal housing (C) with a screwdriver. Remove the secondary catch (D) on the
connector and disconnect the optic cable coming
from the OnStar(R) control modules.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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10.4. Remove the end cap from the new optic cable, connect to the connector and refit the
secondary catch (D). Fit the terminal housing (C) to the
connector and refit the locking strip (B).
10.5. Secure the old optic cable together with the new one (E).
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
Important:
Secure the wiring harness so that there is no risk of chafing and rattling.
11. CV: Remove the rear seat in accordance with WIS - 8. Body - Interior equipment Adjustment/Replacement. The O-bus connector H2-9 is located behind the left speaker.
12. M04-05: Disconnect the optic cables on the OnStar(R) control modules and join the cables:
12.1. Cut off the cable tie holding the connector (H2-9) against REC.
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12.2. Cars with brackets for e.g. an amplifier: Remove the pin strap (A) from the bracket and
remove the tape (B) holding the optic cables.
12.3. Remove the locking strip (C) on the 2-pin connector (H2-9). Open the terminal housing with a
screwdriver. Remove the secondary catch (E)
on the connector and remove the optic cables coming from the OnStar(R) control modules.
12.4. Loosen one of the optic cables remaining in H2-9 (F), connect it to the connector and fit the
secondary catch (E). Connect the connector so
that the optic cables are opposite each other (G). Connect the terminal housing (D) and refit the
locking strip (C).
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Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.5. Cars with brackets for e.g. an amplifier: Fit the cable tie (11 900 515) to the wiring harness
approx. 100 mm (4 in) from H2-9, fit the cable
tie (H) to the bracket. Gather the optic cable in a gentle loop (I) and then place the loop behind the
bracket.
Important:
The optic cable must not be bent with a radius less than 25 mm (1 in).
12.6. Cars without brackets for e.g. an amplifier: Gather the optic cable in a gentle loop (J) and
secure with cable tie.
13. CV: Fit the left-hand, rear side hatch trim in accordance with WIS - 8. Body - Interior equipment
- Adjustment/Replacement.
14. Fit the ground cable to the battery's negative terminal.
15. Carry out procedures after disconnecting the battery, see WIS - 3. Electrical System - Charging
system - Adjustment/Replacement.
Important:
Follow Tech 2(R) on-screen instructions.
16. Add ECU ICM, choose without OnStar(R). See WIS-General-Tech 2(R) - Description and
Operation - Add/Remove.
2000-2004 Saab 9-5
2000-2004 Saab 9-5
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1. Remove the ground cable from the battery's negative cable.
2. Remove the center console, see WIS - Body - Interior.
3. Loosen the gear shift housing (A).
AUT: Disconnect the 6-pin connector (B) to improve access to the gear shift housing screws.
4. Disconnect the signal cable from the SRS control module to the OnStar(R) control module and
secure the cable.
4.1. Disconnect the connector (A) from the SRS control module and cut the cable tie (B).
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4.2. Release the back end of the connector (C) and remove from the contact rail (D).
4.3. M00-01: Disconnect pin 39, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.4. M02-04: Disconnect pin 58, cut off the cable terminal and insulate the end using tape (E). Fold
back the cable and secure using tape (F).
4.5. Assemble the contact rail and end.
4.6. Connect connector (A) and secure the cable using a cable tie (B).
5. Assemble the gear shift housing (A).
AUT: Connect connector (B).
6. Assemble the center console, see WIS - Body - Interior.
7. Remove the OnStar(R) control module and secure the cable harness:
7.1. 5D: Remove the right-hand cover from the luggage compartment floor.
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7.2. Remove the console (A).
7.3. Disconnect the connector (B) from the OnStar(R) control module.
Important:
Secure the cable harness to prevent the risk of scraping and rattling.
7.4. Fold back the cable harness and tape down the connector (C). Fold back the cable harness
again and secure with cable ties (D).
7.5. 5D: Assemble the right-hand cover for the luggage compartment floor.
8. Fit the ground cable on the battery's negative cable.
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9. Erase the diagnostic trouble codes.
10. Set the date and time, see WIS - 3. Electrical system - Information display (SID) - Technical
description.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Global
Positioning System Module > Component Information > Technical Service Bulletins > Service Manual - Revised OnStar(R)
VIU & VCU Replacement
Global Positioning System Module: Technical Service Bulletins Service Manual - Revised
OnStar(R) VIU & VCU Replacement
File In Section: 08 - Body and Accessories
Bulletin No.: 02-08-46-011
Date: September, 2002
SERVICE MANUAL UPDATE
Subject: Revised OnStar(R) Vehicle Interface Unit (VIU) Replacement and OnStar(R) Vehicle
Communication Unit (VCU) Replacement Reconfiguration Procedure
Models: 2001-2002 Buick LeSabre, Park Avenue 2002 Buick Rendezvous 2001 Cadillac Catera,
DeVille, Seville 2001-2002 Cadillac Eldorado 2001 Chevrolet Blazer, Impala, Monte Carlo
2001-2002 Chevrolet Silverado, Suburban, Tahoe, Venture 2001 GMC Envoy, Jimmy 2001-2002
GMC Sierra, Yukon, Yukon XL 2001 Oldsmobile Bravada, Intrigue 2001-2002 Oldsmobile Aurora,
Silhouette 2001-2002 Pontiac Aztek, Bonneville, Grand Prix, Montana with Generation 3 OnStar(R)
(RPO UE1)
This bulletin is being issued to revise the reconfiguration procedure found in the OnStar(R) Vehicle
Interface Unit (VIU) Replacement and the OnStar(R) Vehicle Communication Unit (VCU)
Replacement procedures in the Cellular Communication sub-section of the Service Manual. Please
replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Due to a new process for configuring replacement Generation 3 (formerly 2.6) OnStar(R) modules
for the OnStar(R) Personal Calling feature, vehicles equipped with this version of the system will
require a revised OnStar(R) Reconfiguration procedure in the event of module replacement. In
addition, the Station Identification Number (STID) and Electronic Serial Number (ESN) numbers
are currently accessible by means of the scan tool The procedures for both the Vehicle Interface
Unit and Vehicle Communication Unit differ only in which number (STID or ESN) is recorded and
transferred to the OnStar(R) Call Center.
Important:
After replacing the VIU or VCU, you must reconfigure the OnStar(R) system. Failure to reconfigure
the system will result in an additional customer visit for repair.
1. Press and hold the white Dot button until the OnStar(R) status LED turns from green to red, and
back again to green.
2. Install a scan tool. Use the ID information menu to access the new STID (VIU) or ESN (VCU)
number.
3. Move the vehicle to an open area that is away from tall buildings and with a clear view of
unobstructed sky. Allow the vehicle to run for 10 minutes.
4. Press the blue OnStar(R) button to connect to the OnStar(R) Call Center. Tell the advisor that
this vehicle has received a new VIU or VCU and ask the advisor to perform the following
procedure:
5. Add the new STID (VIU) or ESN (VCU) to update the customer's account.
6. Follow any additional instructions from the OnStar(R) advisor.
7. Ask the advisor to activate the OnStar(R) Personal Calling feature, if available.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Global
Positioning System Module > Component Information > Technical Service Bulletins > Service Manual - Revised OnStar(R)
VIU & VCU Replacement > Page 289
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Navigation Module > Component Information > Technical Service Bulletins > Service Manual - Revised OnStar(R) VIU &
VCU Replacement
Navigation Module: Technical Service Bulletins Service Manual - Revised OnStar(R) VIU & VCU
Replacement
File In Section: 08 - Body and Accessories
Bulletin No.: 02-08-46-011
Date: September, 2002
SERVICE MANUAL UPDATE
Subject: Revised OnStar(R) Vehicle Interface Unit (VIU) Replacement and OnStar(R) Vehicle
Communication Unit (VCU) Replacement Reconfiguration Procedure
Models: 2001-2002 Buick LeSabre, Park Avenue 2002 Buick Rendezvous 2001 Cadillac Catera,
DeVille, Seville 2001-2002 Cadillac Eldorado 2001 Chevrolet Blazer, Impala, Monte Carlo
2001-2002 Chevrolet Silverado, Suburban, Tahoe, Venture 2001 GMC Envoy, Jimmy 2001-2002
GMC Sierra, Yukon, Yukon XL 2001 Oldsmobile Bravada, Intrigue 2001-2002 Oldsmobile Aurora,
Silhouette 2001-2002 Pontiac Aztek, Bonneville, Grand Prix, Montana with Generation 3 OnStar(R)
(RPO UE1)
This bulletin is being issued to revise the reconfiguration procedure found in the OnStar(R) Vehicle
Interface Unit (VIU) Replacement and the OnStar(R) Vehicle Communication Unit (VCU)
Replacement procedures in the Cellular Communication sub-section of the Service Manual. Please
replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Due to a new process for configuring replacement Generation 3 (formerly 2.6) OnStar(R) modules
for the OnStar(R) Personal Calling feature, vehicles equipped with this version of the system will
require a revised OnStar(R) Reconfiguration procedure in the event of module replacement. In
addition, the Station Identification Number (STID) and Electronic Serial Number (ESN) numbers
are currently accessible by means of the scan tool The procedures for both the Vehicle Interface
Unit and Vehicle Communication Unit differ only in which number (STID or ESN) is recorded and
transferred to the OnStar(R) Call Center.
Important:
After replacing the VIU or VCU, you must reconfigure the OnStar(R) system. Failure to reconfigure
the system will result in an additional customer visit for repair.
1. Press and hold the white Dot button until the OnStar(R) status LED turns from green to red, and
back again to green.
2. Install a scan tool. Use the ID information menu to access the new STID (VIU) or ESN (VCU)
number.
3. Move the vehicle to an open area that is away from tall buildings and with a clear view of
unobstructed sky. Allow the vehicle to run for 10 minutes.
4. Press the blue OnStar(R) button to connect to the OnStar(R) Call Center. Tell the advisor that
this vehicle has received a new VIU or VCU and ask the advisor to perform the following
procedure:
5. Add the new STID (VIU) or ESN (VCU) to update the customer's account.
6. Follow any additional instructions from the OnStar(R) advisor.
7. Ask the advisor to activate the OnStar(R) Personal Calling feature, if available.
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Navigation Module > Component Information > Technical Service Bulletins > Service Manual - Revised OnStar(R) VIU &
VCU Replacement > Page 294
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment >
Parking Assist Control Module > Component Information > Diagrams
Parking Assist Control Module: Diagrams
Rear Object Sensor Control Module Part 1
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Parking Assist Control Module > Component Information > Diagrams > Page 298
Rear Object Sensor Control Module Part 2
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Parking Assist Control Module: Service and Repair
REMOVAL PROCEDURE
1. Lift the right rear seating surface up to gain access to the rear parking aid module. 2. Disconnect
the electrical connector from the module. 3. Remove the module retainer. 4. Remove the module
from the seat frame.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
1. Install the module to the seat frame.
Tighten Tighten the module retainer to 1.7 N.m (15 lb in).
2. Connect the electrical connector. 3. Lower the seating surface.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 >
Electrical - MIL ON/DTC's Set By Various Control Modules
Relay Module: Customer Interest Electrical - MIL ON/DTC's Set By Various Control Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 >
Electrical - MIL ON/DTC's Set By Various Control Modules > Page 308
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 >
Electrical - MIL ON/DTC's Set By Various Control Modules > Page 309
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 >
Electrical - MIL ON/DTC's Set By Various Control Modules > Page 310
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 09-06-03-004D > Dec >
10 > Electrical - MIL ON/DTC's Set By Various Control Modules
Relay Module: All Technical Service Bulletins Electrical - MIL ON/DTC's Set By Various Control
Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 09-06-03-004D > Dec >
10 > Electrical - MIL ON/DTC's Set By Various Control Modules > Page 316
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 09-06-03-004D > Dec >
10 > Electrical - MIL ON/DTC's Set By Various Control Modules > Page 317
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 09-06-03-004D > Dec >
10 > Electrical - MIL ON/DTC's Set By Various Control Modules > Page 318
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Accessories and Optional Equipment > Relay
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Relay Module: >
02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Mirror Control
Module > Component Information > Diagrams
Power Mirror Control Module: Diagrams
Memory Mirror Module Connector C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Mirror Control
Module > Component Information > Diagrams > Page 333
Memory Mirror Module Connector C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Mirror Control
Module > Component Information > Service and Repair > Procedures
Power Mirror Control Module: Procedures
The mirror relearn procedure, when initiated, commands the Memory Mirror Module (MMM) to
control the driver and then the passenger mirror in the left, right, up and down directions. When
commanding the mirrors the MMM also learns the direction of horizontal and vertical position
sensor signal circuit feedback voltages. To initiate the relearn procedure, perform the following:
1. With a scan tool, select Memory Mirror Module 2. Select Special Functions 3. Select Output
Controls 4. Select Mirror Relearn 5. Then press the Reset button
If the mirror relearn procedure does not control the driver and passenger mirrors as described,
there may be another fault in the mirror systems. Refer to Diagnostic System Check - Door
Systems to begin the diagnosis of the mirror system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Mirror Control
Module > Component Information > Service and Repair > Procedures > Page 336
Power Mirror Control Module: Removal and Replacement
REMOVAL PROCEDURE
1. Remove the drivers side door panel. 2. Remove the screws (1) that retain the accessory and
outside rear view mirror module from the door panel. 3. Remove the nut (2) that retains the
accessory and outside rear view mirror module from the door panel. 4. Remove the module from
the door panel.
INSTALLATION PROCEDURE
1. Install the module to the door panel.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the nut (2) that retains the accessory and outside rear view mirror module to the door
panel.
Tighten Tighten the module retaining nut to 0.6 N.m (5 lb in).
3. Install the screws (1) that retain the accessory and outside rear view mirror module to the door
panel.
Tighten Tighten the module retaining screws to 0.6 N.m (5 lb in).
4. Install the drivers door panel. 5. Perform the memory mirror module learn procedure. Refer to
Memory Mirror Module (MMM) Learn Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations > Page 340
Power Seat Control Module: Diagrams
Memory Seat Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations > Page 341
Memory Seat Module - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations > Page 342
Memory Seat Module - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations > Page 343
Power Seat Control Module: Service and Repair
MEMORY SEAT CONTROL MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Remove the seat trim panel. 2. Remove the seal cushion. 3. Disconnect the harness connectors
(2). 4. Remove the memory module retaining screws (1).
5. Slide the module out. 6. Remove the module from the vehicle.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Power Seat Control
Module > Component Information > Locations > Page 344
1. Slide the module in until seated.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the memory module retaining screws (1).
Tighten Tighten the screws to 3 N.m (26 lb in).
3. Connect the harness connectors (2).
4. Install the seat cushion. 5. Install the seat trim panel. 6. It a new memory seat module is
installed, the seat needs to be synchronized:
6.1. Operate the seat in all directions: ^
Front tilt
^ Rear tilt
^ Horizontal
^ Recline
6.2. If the seat stops part way due to programmed soft stop, release the switch and operate again
in the same direction till the seat touches the mechanical stop
6.3. Repeat the above for all seat moving axes.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Seat Heater Control
Module > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Seat Heater Control
Module > Component Information > Locations > Page 348
Seat Heater Control Module: Diagrams
Heated Seat Module - LR
Heated Seat Module - RR
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Sunroof / Moonroof
Module > Component Information > Diagrams
Sunroof / Moonroof Module: Diagrams
Sunroof Module Part 1
Sunroof Module Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Sunroof / Moonroof
Module > Component Information > Diagrams > Page 352
Sunroof / Moonroof Module: Service and Repair
POWER SUNROOF MODULE REPLACEMENT
REMOVAL PROCEDURE
1. The sunroof glass panel must be in the closed position. 2. Remove the headliner. 3. Remove the
sunroof glass panel. 4. Remove the drain channel. 5. Remove the sunshade. 6. Remove the 9
bolts retaining the module to the roof. 7. Remove the module from the vehicle.
INSTALLATION PROCEDURE
1. Install the module to the vehicle.
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Body and Frame > Sunroof / Moonroof
Module > Component Information > Diagrams > Page 353
2. Loosely install the 9 bolts retaining the module to the roof.
Use a drill bit to align the 2 holes (6 and 7).
Tighten Tighten the bolts in the sequence shown to 9 N.m (80 lb in).
3. Install the sunshade. 4. Install the drain channel. 5. Install the sunroof glass panel. 6. Install the
headliner. 7. Inspect the operation of the sunroof.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest for Electronic Brake
Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Electronic Brake Control Module: Customer Interest Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest for Electronic Brake
Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 363
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins for
Electronic Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Electronic Brake Control Module: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins for
Electronic Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set >
Page 369
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Page 370
Electronic Brake Control Module: Specifications
EBCM to BPMV Torx Bolts ..................................................................................................................
................................................. 5 Nm (39 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Page 371
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 374
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 375
Electronic Brake Control Module: Diagrams C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 376
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 377
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 378
Electronic Brake Control Module: Diagrams
C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 379
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 380
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 381
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 382
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
Electronic Brake Control Module (EBCM) Replacement (w/o JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the electrical
connectors from the EBCM. 5. Loosen or remove 3 bolts (4) securing the EHCU mounting bracket
(3) to the frame rail (5).
6. Gently move the EHCU down enough to remove the four mounting screws that fasten the
EBCM(2) to the BPMV(1). 7. Remove the EBCM (2) from the BPMV (1). Removal may require a
light amount of force. 8. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
Important: Do not reuse the old mounting screws. Always install new mounting screws with the new
EBCM.
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
385
1. Install the EBCM (2) on to the BPMV(1).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
3. Install or tighten three EHCU bracket mounting bolts.
Tighten the EHCU bracket mounting bolts to 25 Nm (18 ft. lbs.).
4. Connect the electrical connectors to the EBCM. 5. Lower the vehicle. 6. Connect the negative
battery cable. 7. Revise the tire calibration using the Scan Tool Tire Size Calibration function. 8.
Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
386
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
(W/JL4)
Electronic Brake Control Module (EBCM) Replacement (w/ JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the brake fluid
pressure sensor (7) and pressure accumulator switch (4) electrical connectors.
5. Remove the four mounting screws that fasten the EBCM (2) to the BPMV (1). 6. Remove the
EBCM (2) from the BPMV (1). Removal may require a light amount of force.
Important: Note the routing of the jumper harnesses for reinstallation.
7. Remove the EBCM and jumper harnesses from the vehicle. 8. Remove the jumper harnesses
from the EBCM 9. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
1. Install the jumper harnesses to the EBCM. 2. Install the EBCM and jumper harnesses to the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
387
Important: ^
Do not reuse the old mounting screws. Always install new mounting screws with the new EBCM.
^ Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
3. Install the EBCM (2) on to the BPMV (1).
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
5. Connect the brake fluid pressure sensor (7) and pressure accumulator switch (4) electrical
connectors. 6. Lower the vehicle. 7. Connect the negative battery cable. 8. Revise the tire
calibration using the Scan Tool Tire Size Calibration function. 9. Return to Diagnostic Starting Point
- Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Brakes and Traction Control > Traction
Control Module > Component Information > Diagrams
Inverting Driver Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Cruise Control > Cruise Control Module >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Cruise Control > Cruise Control Module >
Component Information > Locations > Page 395
Cruise Control Module (CCM)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Cruise Control > Cruise Control Module >
Component Information > Locations > Page 396
Cruise Control Module: Service and Repair
REMOVAL PROCEDURE
1. Remove the bolts that retain the upper fender brace assembly. 2. Remove the upper fender
brace assembly.
3. Disconnect the electrical connector at the cruise control module. 4. Remove the nuts retaining
the cruise control module to the cowl.
5. Disconnect the cruise control cable from the module. 6. Remove the cruise control module from
the vehicle.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Cruise Control > Cruise Control Module >
Component Information > Locations > Page 397
1. Install the cruise control module to the vehicle. 2. Connect the cruise control cable to the cruise
control module.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the nuts in order to retain the cruise control module to the cowl.
Tighten Tighten the nuts to 9 N.m (8O lb in).
4. Connect the electrical connector at the cruise control module.
5. Install the brace.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Cruise Control > Cruise Control Module >
Component Information > Locations > Page 398
Tighten Tighten the bolts to 9 N.m (80 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Blower Motor Relay > Component
Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Compressor Clutch Relay >
Component Information > Locations
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Compressor Clutch Relay >
Component Information > Locations > Page 406
Compressor Clutch Relay: Service and Repair
COMPRESSOR RELAY REPLACEMENT
REMOVAL PROCEDURE
1. Remove the cover from the underhood convenience center (1). 2. Remove the compressor relay
(2).
INSTALLATION PROCEDURE
1. Install the compressor relay (2). 2. Install the cover to the underhood convenience center (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Technical Service Bulletins > Customer Interest for Control Module HVAC: > 04-01-39-007 > Jun > 04 > A/C Loss of Mode or Temperature Control
Control Module HVAC: Customer Interest A/C - Loss of Mode or Temperature Control
Bulletin No.: 04-01-39-007
Date: June 17, 2004
TECHNICAL
Subject: Loss Of HVAC System Mode and/or Temperature Control (Replace HVAC Control
Module)
Models: 2002 Cadillac Escalade, Escalade EXT 1999-2002 Chevrolet Silverado, Suburban, Tahoe
2002 Chevrolet Avalanche 1999-2002 GMC Denali, Sierra, Yukon, Yukon XL 2001 GMC Sierra C3
2002 GMC Sierra Denali with Automatic HVAC System (RPO C68)
Condition
Some customers may comment that they cannot control the HVAC system modes and/or the
temperature. These concerns may be intermittent.
Cause
An HVAC control module logic lock-up may be the cause of these conditions.
Correction
Important:
Prior to replacing the HVAC control head, review Corporate Bulletin Number 01-01-39-007.
Replace the HVAC control module. Refer to the HVAC Control Module Replacement procedure in
the HVAC System - Automatic sub-section of the Service Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Technical Service Bulletins > Customer Interest for Control Module HVAC: > 04-01-39-007 > Jun > 04 > A/C Loss of Mode or Temperature Control > Page 415
Part Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Control Module HVAC: > 04-01-39-007 > Jun
> 04 > A/C - Loss of Mode or Temperature Control
Control Module HVAC: All Technical Service Bulletins A/C - Loss of Mode or Temperature Control
Bulletin No.: 04-01-39-007
Date: June 17, 2004
TECHNICAL
Subject: Loss Of HVAC System Mode and/or Temperature Control (Replace HVAC Control
Module)
Models: 2002 Cadillac Escalade, Escalade EXT 1999-2002 Chevrolet Silverado, Suburban, Tahoe
2002 Chevrolet Avalanche 1999-2002 GMC Denali, Sierra, Yukon, Yukon XL 2001 GMC Sierra C3
2002 GMC Sierra Denali with Automatic HVAC System (RPO C68)
Condition
Some customers may comment that they cannot control the HVAC system modes and/or the
temperature. These concerns may be intermittent.
Cause
An HVAC control module logic lock-up may be the cause of these conditions.
Correction
Important:
Prior to replacing the HVAC control head, review Corporate Bulletin Number 01-01-39-007.
Replace the HVAC control module. Refer to the HVAC Control Module Replacement procedure in
the HVAC System - Automatic sub-section of the Service Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Control Module HVAC: > 04-01-39-007 > Jun
> 04 > A/C - Loss of Mode or Temperature Control > Page 421
Part Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Technical Service Bulletins > Page 422
Blower Motor Control Processor - Auxiliary (Tahoe/Yukon)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Service and Repair > HVAC System - Automatic
Control Module HVAC: Service and Repair HVAC System - Automatic
HVAC Control Module Replacement
REMOVAL PROCEDURE
1. Remove the instrument panel accessory trim plate. 2. Remove the screws from the HVAC
control module. 3. Depress the control assembly retaining tabs and remove the HVAC control
module from the instrument panel. 4. Disconnect the electrical connectors from the HVAC control
module.
INSTALLATION PROCEDURE
1. Connect the electrical connectors to the HVAC control module. 2. Install the HVAC control
module into the instrument panel, ensuring that the HVAC control module retaining tabs lock into
place.
NOTE: Use the correct fastener in the correct location. Replacement fasteners must be the correct
part number for that application. Fasteners requiring replacement or fasteners requiring the use of
thread locking compound or sealant are identified in the service procedure. Do not use paints,
lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These
coatings affect fastener torque and joint clamping force and may damage the fastener. Use the
correct tightening sequence and specifications when installing fasteners in order to avoid damage
to parts and systems.
3. Install the screws to the HVAC control module.
Tighten
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Service and Repair > HVAC System - Automatic > Page 425
Tighten the screws to 1.9 N.m (17 lb in).
4. Install the instrument panel accessory trim plate.
Important: Do not adjust any controls on the HVAC control module while the HVAC control module
is calibrating.
If interrupted improper HVAC performance will result.
5. Start the vehicle and let run for one minute.
HVAC Control Module Replacement - Auxiliary
REMOVAL PROCEDURE
1. Separate the front of the console (1) from the headliner by pushing forward and pulling down in
front. 2. Remove the HVAC control assembly (2) by releasing the tabs at the rear of the control.
Push out from the back through the console. 3. Disconnect the electrical connector (3).
INSTALLATION PROCEDURE
1. Connect the electrical connector (3). 2. Install the HVAC control assembly (2) to the console (1).
3. Install the console to the headliner.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Service and Repair > HVAC System - Automatic > Page 426
Control Module HVAC: Service and Repair HVAC System - Manual
HVAC CONTROL PROCESSOR REPLACEMENT - AUXILIARY
REMOVAL PROCEDURE
1. Remove the auxiliary rear HVAC control assembly. 2. Remove the auxiliary HVAC control
processor (2) from the bracket (3).
3. Remove the cover from the auxiliary HVAC control processor (2). 4. Remove the auxiliary HVAC
control processor (2) from the box (1).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > Control Module HVAC > Component
Information > Service and Repair > HVAC System - Automatic > Page 427
1. Install the auxiliary HVAC control processor (2) to the box. (1) 2. Install the cover to the auxiliary
HVAC control processor (2).
3. Install the auxiliary HVAC control processor (2) to the bracket (3). 4. Install the auxiliary rear
HVAC control assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > System Relay, HVAC > Component
Information > Locations
System Relay: Locations
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - HVAC > System Relay, HVAC > Component
Information > Locations > Page 431
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC
Instrument Panel Control Module: Customer Interest Brakes - 'Reduced Brake Power' Shown on
DIC
File In Section: 05 - Brakes
Bulletin No.: 02-05-23-004
Date: October, 2002
TECHNICAL
Subject: Driver's Information Center (DIC) "Reduced Brake Power" Message, Reduced Vacuum
Boost (Inspect/Replace Intake Manifold and Recalibrate the Instrument Panel Cluster (IPC))
Models: 2002-2003 Cadillac Escalade 2WD 2002-2003 Chevrolet Avalanche 1500 Series,
Silverado, Suburban, Tahoe 2002-2003 GMC Sierra, Yukon, Yukon XL with Power Vacuum Boost
Brake System (RPOs JC3 and JC4)
Condition Some customers may comment on a "Reduced Brake Power" message on the DIC.
Cause It is possible that a very small number of 2002 and 2003 model year vehicles may have a
restriction in the vacuum booster port on the intake manifold. On the 2003 model year, only the IPC
calibration is the cause of the DIC message.
Correction Important:
Only inspect suspect vehicles built between June 13, 2002 and August 9, 2002.
Follow the service procedure to diagnose and correct this condition.
1. Open the hood and install fender covers.
2. Loosen the engine sight shield bolt. The bolt should stay in the shield.
3. Remove the engine sight shield from the sight shield retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 441
4. Inspect the left front corner of the intake manifold for a "C" with a circle around it (2). ^
If the intake manifold DOES have a "C" (2) on it, continue with Step 5.
^ If the intake manifold DOES NOT have a "C" (2) on it, continue with Step 19.
5. Disconnect the accelerator control cable clip from the engine sight shield retainer.
6. Disconnect the cruise control cable clip from the retainer if equipped.
7. Remove the engine sight shield retainer bolts and the retainer if equipped.
8. Inspect rear center of the intake manifold just below the recycle symbol for "MADE IN CANADA"
(2). ^
If the intake manifold DOES have "MADE IN CANADA" (1) on it, continue with Step 9
^ If the intake manifold DOES NOT have "MADE IN CANADA" (1) on it, continue with Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 442
9. Locate the vacuum booster port connector (1) on the left rear of the intake manifold.
10. Gently pull out on the vacuum booster hose (2).
11. With two fingers, push in the vacuum booster port connector lock ring (3) while gently pulling
out on the vacuum booster hose (2).
Important:
^ DO NOT force the drill bit into the vacuum booster intake port.
^ If the vacuum booster intake port is restricted, DO NOT attempt to remove the restriction with the
drill bit.
^ If the restriction is removed with the drill bit, the material from the restriction may cause internal
engine damage.
^ If the vacuum booster port is restricted, the intake manifold must be replaced.
12. Inspect the vacuum booster intake port with a 8.7 mm (11/32 in) drill bit, maximum length of
127 mm (5 in).
13. Insert the drill bit approximately 63.5 mm (2.5 in) into the vacuum booster intake port.
^ If the vacuum booster intake port IS restricted, continue with Step 14.
^ If the vacuum booster intake port IS NOT restricted, continue with Step 15.
14. Replace the intake manifold. Refer to Intake Manifold Replacement (SI Document ID #
753666).
15. Reinstall the vacuum booster hose to the vacuum booster intake port by pushing to hose nipple
into the connector.
16. Install the engine sight shield retainer and the bolts.
Tighten
Tighten the engine sight shield retainer bolts to 5 N.m (44 lb in).
17. Install the cruise control cable clip to the retainer.
18. Install the accelerator control cable clip to the retainer if equipped.
19. Install the engine sight shield to the retainer if equipped.
Tighten
Tighten the engine sight shield bolt to 10 N.m (89 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 443
20. Start the engine and fully apply the brakes four or five times in order to ensure a "good" brake
pedal.
Recalibrating the IPC (2003 Model Year Vehicles)
1. Vehicles Built Prior To the following VIN Breakpoints
^ 3G104569
^ 3E117608
^ 31118369
^ 3Z120443
^ 3R107568
^ 3J101720
2. Plug in Tech 2.
3. Set the parking brake and turn the ignition ON with the engine off.
4. Reprogram the IPC following normal SPS procedures (TIS Version 9 released August 2002 or
newer).
5. After reprogramming the IPC, start the vehicle and fully apply the brakes four to five times in
order to ensure a "good" brake pedal and that there are no messages on the DIC.
Important:
The Owner's Manual Must Be Replaced After The IPC Is Recalibrated.
^ A new Owner's Manual can be ordered from Helm @ 1-800-551-4123. The dealer will be billed
for the new Manual and reimbursed through the warranty claims system.
^ The Owner's Manual will be shipped to the dealer. Dealers will be required to mail the Manual to
the customer.
Parts Information Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 444
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 02-05-23-004 > Oct > 02
> Brakes - 'Reduced Brake Power' Shown on DIC
Instrument Panel Control Module: All Technical Service Bulletins Brakes - 'Reduced Brake Power'
Shown on DIC
File In Section: 05 - Brakes
Bulletin No.: 02-05-23-004
Date: October, 2002
TECHNICAL
Subject: Driver's Information Center (DIC) "Reduced Brake Power" Message, Reduced Vacuum
Boost (Inspect/Replace Intake Manifold and Recalibrate the Instrument Panel Cluster (IPC))
Models: 2002-2003 Cadillac Escalade 2WD 2002-2003 Chevrolet Avalanche 1500 Series,
Silverado, Suburban, Tahoe 2002-2003 GMC Sierra, Yukon, Yukon XL with Power Vacuum Boost
Brake System (RPOs JC3 and JC4)
Condition Some customers may comment on a "Reduced Brake Power" message on the DIC.
Cause It is possible that a very small number of 2002 and 2003 model year vehicles may have a
restriction in the vacuum booster port on the intake manifold. On the 2003 model year, only the IPC
calibration is the cause of the DIC message.
Correction Important:
Only inspect suspect vehicles built between June 13, 2002 and August 9, 2002.
Follow the service procedure to diagnose and correct this condition.
1. Open the hood and install fender covers.
2. Loosen the engine sight shield bolt. The bolt should stay in the shield.
3. Remove the engine sight shield from the sight shield retainer.
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4. Inspect the left front corner of the intake manifold for a "C" with a circle around it (2). ^
If the intake manifold DOES have a "C" (2) on it, continue with Step 5.
^ If the intake manifold DOES NOT have a "C" (2) on it, continue with Step 19.
5. Disconnect the accelerator control cable clip from the engine sight shield retainer.
6. Disconnect the cruise control cable clip from the retainer if equipped.
7. Remove the engine sight shield retainer bolts and the retainer if equipped.
8. Inspect rear center of the intake manifold just below the recycle symbol for "MADE IN CANADA"
(2). ^
If the intake manifold DOES have "MADE IN CANADA" (1) on it, continue with Step 9
^ If the intake manifold DOES NOT have "MADE IN CANADA" (1) on it, continue with Step 16.
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Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 02-05-23-004 > Oct > 02
> Brakes - 'Reduced Brake Power' Shown on DIC > Page 451
9. Locate the vacuum booster port connector (1) on the left rear of the intake manifold.
10. Gently pull out on the vacuum booster hose (2).
11. With two fingers, push in the vacuum booster port connector lock ring (3) while gently pulling
out on the vacuum booster hose (2).
Important:
^ DO NOT force the drill bit into the vacuum booster intake port.
^ If the vacuum booster intake port is restricted, DO NOT attempt to remove the restriction with the
drill bit.
^ If the restriction is removed with the drill bit, the material from the restriction may cause internal
engine damage.
^ If the vacuum booster port is restricted, the intake manifold must be replaced.
12. Inspect the vacuum booster intake port with a 8.7 mm (11/32 in) drill bit, maximum length of
127 mm (5 in).
13. Insert the drill bit approximately 63.5 mm (2.5 in) into the vacuum booster intake port.
^ If the vacuum booster intake port IS restricted, continue with Step 14.
^ If the vacuum booster intake port IS NOT restricted, continue with Step 15.
14. Replace the intake manifold. Refer to Intake Manifold Replacement (SI Document ID #
753666).
15. Reinstall the vacuum booster hose to the vacuum booster intake port by pushing to hose nipple
into the connector.
16. Install the engine sight shield retainer and the bolts.
Tighten
Tighten the engine sight shield retainer bolts to 5 N.m (44 lb in).
17. Install the cruise control cable clip to the retainer.
18. Install the accelerator control cable clip to the retainer if equipped.
19. Install the engine sight shield to the retainer if equipped.
Tighten
Tighten the engine sight shield bolt to 10 N.m (89 lb in).
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Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 02-05-23-004 > Oct > 02
> Brakes - 'Reduced Brake Power' Shown on DIC > Page 452
20. Start the engine and fully apply the brakes four or five times in order to ensure a "good" brake
pedal.
Recalibrating the IPC (2003 Model Year Vehicles)
1. Vehicles Built Prior To the following VIN Breakpoints
^ 3G104569
^ 3E117608
^ 31118369
^ 3Z120443
^ 3R107568
^ 3J101720
2. Plug in Tech 2.
3. Set the parking brake and turn the ignition ON with the engine off.
4. Reprogram the IPC following normal SPS procedures (TIS Version 9 released August 2002 or
newer).
5. After reprogramming the IPC, start the vehicle and fully apply the brakes four to five times in
order to ensure a "good" brake pedal and that there are no messages on the DIC.
Important:
The Owner's Manual Must Be Replaced After The IPC Is Recalibrated.
^ A new Owner's Manual can be ordered from Helm @ 1-800-551-4123. The dealer will be billed
for the new Manual and reimbursed through the warranty claims system.
^ The Owner's Manual will be shipped to the dealer. Dealers will be required to mail the Manual to
the customer.
Parts Information Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use table.
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> Brakes - 'Reduced Brake Power' Shown on DIC > Page 453
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair
Grounding Point: All Technical Service Bulletins Electrical - Information For Electrical Ground
Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 459
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 460
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 461
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 462
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 463
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
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Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 464
For vehicles repaired under warranty, use the table.
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Grounding Point: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 469
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 475
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 476
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 477
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 478
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
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Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 479
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
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Module: > 10-08-45-001B > Oct > 10 > Electrical - Information For Electrical Ground Repair > Page 480
For vehicles repaired under warranty, use the table.
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Instrument Panel > Instrument Panel Control
Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Instrument Panel Control
Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 485
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Brake Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions
Brake Lamp Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 491
Electrical Symbols Part 1
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Component Information > Diagrams > Diagram Information and Instructions > Page 492
Electrical Symbols Part 2
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Component Information > Diagrams > Diagram Information and Instructions > Page 493
Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 494
Electrical Symbols Part 4
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Brake Lamp Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Component Information > Diagrams > Diagram Information and Instructions > Page 496
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Daytime Running Lamp
Control Unit > Component Information > Diagrams > Diagram Information and Instructions
Daytime Running Lamp Control Unit: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Control Unit > Component Information > Diagrams > Diagram Information and Instructions > Page 527
Electrical Symbols Part 3
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Control Unit > Component Information > Diagrams > Diagram Information and Instructions > Page 528
Electrical Symbols Part 4
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Daytime Running Lamp Control Unit: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Control Unit > Component Information > Diagrams > Diagram Information and Instructions > Page 552
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Relay > Component Information > Locations
Daytime Running Lamp Relay: Locations
Fuse Block - Underhood
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Relay > Component Information > Locations > Page 558
Locations View
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Daytime Running Lamp Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Daytime Running Lamp Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Relay > Component Information > Diagrams > Diagram Information and Instructions > Page 590
Conversion - English/Metric
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Relay > Component Information > Diagrams > Page 591
Daytime Running Lamp Relay: Service and Repair
REMOVAL PROCEDURE
1. Open the electrical center cover (2). 2. Using the relays/fuses diagram, locate the DRL relay. 3.
Remove the relay from the underhood electrical center.
INSTALLATION PROCEDURE
1. Refer to the diagram for the relays/fuses in the cover locate the position of the relay. 2. Install the
relay in the electrical center. 3. Install the cover (2). 4. Start and vehicle and shift gear lever out of
park.
Ask an assistant to look in front of vehicle to ensure the DRL are operating.
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> Component Information > Diagrams > Diagram Information and Instructions
Exterior Lighting Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Exterior Lighting Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 608
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 609
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 610
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 611
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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> Component Information > Diagrams > Diagram Information and Instructions > Page 612
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 613
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 614
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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> Component Information > Diagrams > Diagram Information and Instructions > Page 615
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 616
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 617
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 618
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 619
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 620
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Component Information > Diagrams > Diagram Information and Instructions > Page 621
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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> Component Information > Diagrams > Diagram Information and Instructions > Page 623
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 624
Various symbols are used in order to describe different service operations.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 625
Conversion - English/Metric
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> Component Information > Diagrams > Diagram Information and Instructions > Page 626
Roof Beacon Relay
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Fog/Driving Lamp Relay
> Component Information > Locations
Fog/Driving Lamp Relay: Locations
Fuse Block - Underhood
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> Component Information > Locations > Page 630
Locations View
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> Component Information > Diagrams > Diagram Information and Instructions
Fog/Driving Lamp Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 633
Electrical Symbols Part 1
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> Component Information > Diagrams > Diagram Information and Instructions > Page 634
Electrical Symbols Part 2
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Electrical Symbols Part 3
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> Component Information > Diagrams > Diagram Information and Instructions > Page 636
Electrical Symbols Part 4
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Fog/Driving Lamp Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 647
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Fog/Driving Lamp Relay
> Component Information > Diagrams > Diagram Information and Instructions > Page 648
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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> Component Information > Diagrams > Diagram Information and Instructions > Page 649
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 650
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 651
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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> Component Information > Diagrams > Diagram Information and Instructions > Page 652
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 653
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 654
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 655
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 656
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 657
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Component Information > Diagrams > Diagram Information and Instructions > Page 658
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 662
Conversion - English/Metric
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Headlamp Relay >
Component Information > Locations
Headlamp Relay: Locations
Locations View
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Component Information > Locations > Page 666
Fuse Block - Underhood
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Component Information > Diagrams > Diagram Information and Instructions
Headlamp Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Component Information > Diagrams > Diagram Information and Instructions > Page 670
Electrical Symbols Part 2
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Component Information > Diagrams > Diagram Information and Instructions > Page 671
Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 672
Electrical Symbols Part 4
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Headlamp Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Horn Relay >
Component Information > Locations
Horn Relay: Locations
Locations View
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Component Information > Locations > Page 702
Fuse Block - Underhood
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Component Information > Service and Repair
Lamp Control Module: Service and Repair
REMOVAL PROCEDURE
1. Remove the IP trim bezel. 2. Remove the head lamp switch/4WD shift button housing from the
IP by pulling outwards.
The arrows in the graphic shows the locations of the retaining clips.
3. Disconnect all the electrical connectors.
4. Remove the electrical tape around the lamp module and discard. 5. Remove the lamp module
from the connector by pulling outwards.
INSTALLATION PROCEDURE
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1. Install the lamp module to the connector until fully seated.
IMPORTANT: Do not tape past the line where the cooling fins begin. Taping around the fins will
result in the module overheating.
2. Install a new electrical tape around the module in order to secure the module to the IP wire
harness. 3. Connect all the electrical connectors.
4. Install the head lamp switch/4WD shift button housing to the IP so that the retainers are fully
seated. 5. Install the IP trim bezel.
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Component Information > Diagrams > Diagram Information and Instructions
Parking Lamp Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Parking Lamp Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 727
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 728
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 729
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 730
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 731
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 732
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 733
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 734
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 735
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Parking Lamp Relay >
Component Information > Diagrams > Diagram Information and Instructions > Page 736
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Component Information > Diagrams > Diagram Information and Instructions > Page 737
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 738
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 739
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 740
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > Customer Interest for Trailer Lighting Module: > 02-05-22-004C >
Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON
Trailer Lighting Module: Customer Interest Electrical - Trailer Brakes Apply With Headlamps ON
Bulletin No.: 02-05-22-004C
Date: April 05, 2005
TECHNICAL
Subject: Trailer Brakes Applied When Headlights/Park Lamps Are On, Brake Controller Illumination
(Modify Brake Controller Wiring Harness)
Models: 2002-2005 Cadillac Escalade, Escalade EXT 1999-2005 Chevrolet Silverado 2000-2005
Chevrolet Suburban, Tahoe 2002-2005 Chevrolet Avalanche 1999-2005 GMC Sierra 2000-2005
GMC Yukon, Yukon XL 2003-2005 HUMMER H2
Supercede:
This bulletin is being revised to add additional model years. Please discard Corporate Bulletin
Number 02-05-22-004B (Section 05 - Brakes).
Condition
Some customers may comment that when the headlamps or park lamps are on, the brakes on the
trailer are always applied, or that the back lighting for the trailer brake controller only illuminates
when the brakes are applied.
Cause
The cause of this condition may be due to wiring changes within the vehicle electrical system for
the 2003 model year.
Correction
Inspect the brake controller wiring harness jumper that is plugged into the vehicle relay block-body.
The relay block-body is located under the left side of the instrument panel near the left kick panel,
behind a plastic cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > Customer Interest for Trailer Lighting Module: > 02-05-22-004C >
Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON > Page 749
The 1999 though early 2003 wiring harness jumper that plugs into the relay block will have a
reddish/brown 6-way connector and a tag with the last four digits of the wiring harness part
number. Second design 2003-05 may have a white plastic connector with part number 5418 as
well.
^ The 1999 jumper is/was P/N 12171982 with a pink/purple tag identifier of 1982. This number has
been superseded to 15366255, with a pink/purple tag identifier of 6255.
^ The 2000 jumper harness is P/N 15366255. The pink/purple tag identifier is 6255.
^ The 2001-2002 jumper is P/N 15086884. The orange tag identifier is 6884.
^ The 2003-05 jumper is P/N 15085418. The orange tag identifier is 5418.
When transferring the brake controller with the wiring jumper attached from a 2001-2002 vehicle to
a 2003-05 vehicle, a change to the jumper harness connector must be performed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > Customer Interest for Trailer Lighting Module: > 02-05-22-004C >
Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON > Page 750
The information shown is for the 1999-2002 wiring harnesses and for the 2003-05 wiring harness.
To modify a 12171982, 15366255 or 15086884 harness for use in a 2003-05 vehicle, switch the
wires in cavities "A" and "D".
To modify a 15085418 harness for use in a 1999-2002 vehicle (see model list at the front of this
bulletin for applicable models), switch the wires in cavities "A" and "D".
Warranty Information
When the correct wiring harness P/N is matched to the specific model year of the vehicle,
everything works properly.
Therefore, conversion of an incorrect wiring jumper to match the vehicle would not be considered a
warrantable repair.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Trailer Lighting Module: >
02-05-22-004C > Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON
Trailer Lighting Module: All Technical Service Bulletins Electrical - Trailer Brakes Apply With
Headlamps ON
Bulletin No.: 02-05-22-004C
Date: April 05, 2005
TECHNICAL
Subject: Trailer Brakes Applied When Headlights/Park Lamps Are On, Brake Controller Illumination
(Modify Brake Controller Wiring Harness)
Models: 2002-2005 Cadillac Escalade, Escalade EXT 1999-2005 Chevrolet Silverado 2000-2005
Chevrolet Suburban, Tahoe 2002-2005 Chevrolet Avalanche 1999-2005 GMC Sierra 2000-2005
GMC Yukon, Yukon XL 2003-2005 HUMMER H2
Supercede:
This bulletin is being revised to add additional model years. Please discard Corporate Bulletin
Number 02-05-22-004B (Section 05 - Brakes).
Condition
Some customers may comment that when the headlamps or park lamps are on, the brakes on the
trailer are always applied, or that the back lighting for the trailer brake controller only illuminates
when the brakes are applied.
Cause
The cause of this condition may be due to wiring changes within the vehicle electrical system for
the 2003 model year.
Correction
Inspect the brake controller wiring harness jumper that is plugged into the vehicle relay block-body.
The relay block-body is located under the left side of the instrument panel near the left kick panel,
behind a plastic cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Trailer Lighting Module: >
02-05-22-004C > Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON > Page 756
The 1999 though early 2003 wiring harness jumper that plugs into the relay block will have a
reddish/brown 6-way connector and a tag with the last four digits of the wiring harness part
number. Second design 2003-05 may have a white plastic connector with part number 5418 as
well.
^ The 1999 jumper is/was P/N 12171982 with a pink/purple tag identifier of 1982. This number has
been superseded to 15366255, with a pink/purple tag identifier of 6255.
^ The 2000 jumper harness is P/N 15366255. The pink/purple tag identifier is 6255.
^ The 2001-2002 jumper is P/N 15086884. The orange tag identifier is 6884.
^ The 2003-05 jumper is P/N 15085418. The orange tag identifier is 5418.
When transferring the brake controller with the wiring jumper attached from a 2001-2002 vehicle to
a 2003-05 vehicle, a change to the jumper harness connector must be performed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Trailer Lighting Module
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Trailer Lighting Module: >
02-05-22-004C > Apr > 05 > Electrical - Trailer Brakes Apply With Headlamps ON > Page 757
The information shown is for the 1999-2002 wiring harnesses and for the 2003-05 wiring harness.
To modify a 12171982, 15366255 or 15086884 harness for use in a 2003-05 vehicle, switch the
wires in cavities "A" and "D".
To modify a 15085418 harness for use in a 1999-2002 vehicle (see model list at the front of this
bulletin for applicable models), switch the wires in cavities "A" and "D".
Warranty Information
When the correct wiring harness P/N is matched to the specific model year of the vehicle,
everything works properly.
Therefore, conversion of an incorrect wiring jumper to match the vehicle would not be considered a
warrantable repair.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Lighting and Horns > Turn Signal Relay >
Component Information > Diagrams > Diagram Information and Instructions
Turn Signal Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Turn Signal Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Component Information > Diagrams > Diagram Information and Instructions > Page 778
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Component Information > Diagrams > Diagram Information and Instructions > Page 786
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Component Information > Diagrams > Diagram Information and Instructions > Page 791
Conversion - English/Metric
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Power and Ground Distribution > Relay Box >
Component Information > Locations
Locations View
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Component Information > Locations > Page 796
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
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Component Information > Locations > Page 797
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
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Component Information > Locations > Page 798
Junction Block - Rear Lamps - C4
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Power and Ground Distribution > Relay Box >
Component Information > Service and Repair > Relay Replacement (Within an Electrical Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
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1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
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Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
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Locations View
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Body Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Body Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 826
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Body Control Module: Connector Views
Body Control Module Connector (BCM) - C1
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Body Control Module (BCM) - C2
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Body Control Module (BCM) - C3
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Body Control Module: Electrical Diagrams
Controlled/Monitored Subsystem References
Controlled/Monitored Subsystem References
Body Control Module Schematics: Controlled/Monitored Subsystem References
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 844
Exterior Lighting Systems References
Exterior Lighting Systems References
Body Control Module Schematics: Exterior Lighting Systems References
Interior Lighting Systems References
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 845
Interior Lighting Systems References
Body Control Module Schematics: Interior Lighting Systems References
Power, Ground and Serial Data
Power, Ground and Serial Data
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 846
Body Control Module Schematics: Power, Ground And Serial Data
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures
Body Control Module: Procedures
IMPORTANT: If any module is replaced, programming the module with the proper RPO
configurations must be done prior to performing the Passlock Learn procedure.
1. The BCM must be programmed with the proper RPO configurations. The BCM stores the
information regarding the vehicle options. If the BCM is
not properly configured with the correct RPO codes the BCM will not control the features properly.
Ensure that the following conditions exist in order to prepare for BCM programming: ^
The battery is fully charged.
^ The ignition switch is in the RUN position.
^ The DLC is accessible.
^ All disconnected modules and devices are reconnected before programming.
2. Follow the SPS instructions on the Techline Terminal and scan tool to program the BCM. 3. If
the BCM fails to accept the program, perform the following steps:
^ Inspect all BCM connections.
^ Verify that the SPS Techline Terminal and scan tool have the latest software version.
Passlock Learn Procedures Refer to the Theft Deterrent sub-system for the appropriate learn
procedure.
IMPORTANT: After programming, perform the following to avoid future misdiagnosis: 1. Turn the
ignition OFF for 10 seconds. 2. Connect the scan tool to the data link connector. 3. Turn the ignition
ON with the engine OFF. 4. Use the scan tool in order to retrieve History DTCs from all modules. 5.
Clear all history DTCs.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures > Page 849
Body Control Module: Removal and Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
1. Disconnect the negative battery cable(s). 2. Remove the knee bolster.
3. Disconnect the brown connector. 4. Disconnect all other connectors (1). 5. Remove the BCM
from the sliding bracket.
INSTALLATION PROCEDURE
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures > Page 850
1. Slide the BCM onto the bracket. 2. Connect all the connectors (1) except the brown connector. 3.
Connect the brown connector.
4. Install the knee bolster. 5. Connect the negative battery cable(s). 6. Reprogram the BCM.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations
Electronic Throttle Control Module: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 854
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 855
Electronic Throttle Control Module: Diagrams
Throttle Actuator Control (TAC) Module Connector C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 856
Throttle Actuator Control (TAC) Module Connector C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 857
Electronic Throttle Control Module: Description and Operation
THROTTLE ACTUATOR CONTROL (TAC) MODULE
Throttle Actuator Control (TAC) Module
The TAC module is the control center for the electronic throttle system. The TAC module and the
powertrain control module (PCM) communicate via a dedicated redundant serial data circuit. The
TAC module and the PCM monitor the commanded throttle position and compare the commanded
position to the actual throttle position. This is accomplished by monitoring the APP and the TP
sensor. These 2 values must be within a calibrated value of each other. The TAC module also
monitors each individual circuit of the TP sensor and the APP to verify proper operation.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 858
Electronic Throttle Control Module: Service and Repair
THROTTLE ACTUATOR CONTROL (TAC) MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Release the retainer tab from the left side of the throttle actuator control (TAC) module. 2. Slowly
slide the TAC module out of the retaining bracket. 3. Disconnect the TAC module connectors from
the TAC module.
INSTALLATION PROCEDURE
1. Connect the TAC module connectors to the TAC module. 2. Slide the TAC module into the TAC
module bracket. 3. Push the TAC module towards the bracket in order to snap the TAC module into
the bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Engine Control Module: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set > Page 867
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage > Page 873
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set
Engine Control Module: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire
DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set > Page 878
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage > Page 884
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Page 885
Locations View
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions
Engine Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 888
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 889
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 890
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 891
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 892
Engine Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 904
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Engine Control Module: Connector Views
Powertrain Control Module (PCM) C1 Part 1
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Powertrain Control Module (PCM) C1 Part 2
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Powertrain Control Module (PCM) C1 Part 3
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Powertrain Control Module (PCM) C2 Part 1
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Powertrain Control Module (PCM) C2 Part 2
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Powertrain Control Module (PCM) C2 Part 3
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> Electronic Ignition (EI) System Description
Engine Control Module: Description and Operation Electronic Ignition (EI) System Description
POWERTRAIN CONTROL MODULE (PCM)
The PCM controls all ignition system functions, and constantly corrects the basic spark timing. The
PCM monitors information from various sensor inputs that include the following:
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Mass Airflow (MAF) sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Vehicle Speed Sensor (VSS)
^ The transmission gear position or range information sensors
^ The Engine Knock Sensors (KS)
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Engine Control Module: Description and Operation Powertrain Control Module (PCM) Description
General Information
The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while
maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ The fuel control
^ The Ignition Control (IC)
^ The Knock Sensor (KS) system
^ The automatic transmission shift functions
^ The manual transmission
^ The cruise control enable, if equipped
^ The generator
^ The evaporative emissions (EVAP) purge
^ The A/C clutch control, if equipped
^ The secondary air injection (AIR), if equipped
^ The Exhaust Gas Recirculation (EGR)
PCM Function
The PCM supplies a buffered voltage to various sensors and switches. The PCM controls most
components with electronic switches which complete a ground circuit when turned ON.
Powertrain Control Module
Powertrain Control Module
The Powertrain Control Module (PCM) is located in the engine compartment. The PCM is the
control center of the vehicle. The PCM controls the following:
^ The fuel metering system
^ The transmission shifting
^ The ignition timing
^ The on-board diagnostics for powertrain functions
The PCM constantly monitors the information from various sensors and controls the systems that
affect vehicle performance and emissions. The PCM also performs the diagnostic functions for
those systems. The PCM can recognize operational problems and alert the driver through the
Malfunction Indicator Lamp (MIL) when a malfunction has occurred. When a malfunction is
detected, the PCM stores a Diagnostic Trouble Code (DTC) which helps to identify problem areas.
This is done to aid the technician in making repairs.
The PCM supplies either 5.0 or 12.0 volts to power various sensors and switches. This is done
through resistances in the PCM. The resistance is so high in value that a test lamp does not
illuminate when connected to the circuit. In some cases, even an ordinary shop voltmeter does not
give an accurate reading because the voltmeters resistance is too low. Therefore, a DMM with a
minimum of 10 megaohms input impedance is required to ensure accurate voltage readings.
The PCM controls output circuits such as the fuel injectors, the Idle Air Control (IAC), the cooling
fan relays, etc. by controlling the ground or the power feed circuit through transistors or a device
called an output driver module.
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Torque Management
Torque management is a function of the PCM that reduces engine power under certain conditions.
Torque management is performed for the following reasons:
1. To prevent over-stressing the powertrain and driveline components 2. To prevent damage to the
vehicle during certain abusive maneuvers 3. To reduce engine speed when the IAC is out of the
normal operating range
The PCM monitors the following sensors and engine parameters in order to calculate engine output
torque:
^ The air/fuel ratio
^ The Mass Air Flow (MAF) sensor
^ The Manifold Absolute Pressure (MAP) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The spark advance
^ The engine speed
^ The Engine Coolant Temperature (ECT) Sensor
^ The A/C clutch status
The PCM monitors the torque converter status, the transmission gear ratio, and the engine speed
in order to determine if torque reduction is required. The PCM retards the spark as appropriate to
reduce engine torque output if torque reduction is required. The PCM also shuts OFF the fuel to
certain injectors in order to reduce the engine power in the case of an abusive maneuver.
The following are instances when engine power reduction is likely to be experienced:
^ During transmission upshifts and downshifts
^ During heavy acceleration from a standing start
^ When the clutch pedal is released too quick under a heavy load, 6.0L only
^ When one set of drive axles looses traction while the other set of drive axles are not moving, 4
Wheel Drive only and in 4WD low
^ If the IAC is out of the normal operating range, except 6.0L
^ When the driver is performing harsh or abusive maneuvers such as shifting into gear at high
throttle angles or shifting the transmission from reverse to drive to create a rocking motion
The driver is unlikely to notice the torque management actions in the first 2 instances. The engine
power output is moderate at full throttle in the other cases.
The PCM calculates the amount of spark retard necessary to reduce the engine power by the
desired amount. The PCM disables the fuel injectors for cylinders 1, 4, 6, and 7 in the case of an
abusive maneuver.
Basic Knowledge Required
Without a basic knowledge of electricity, you will have difficulty using the diagnostic procedures.
You should understand the basic theory of electricity and know the meaning of voltage-volts,
current-amps, and resistance-ohms. You should understand what happens in a circuit with an open
or a shorted wire. You should be able to read and understand a wiring diagram.
PCM Service Precautions
The PCM is designed to withstand normal current draws associated with vehicle operations. Avoid
overloading any circuit. When testing for opens or shorts, do not ground any of the PCM circuits
unless instructed. When testing for opens or shorts, do not apply voltage to any of the PCM circuits
unless instructed. Only test these circuits with a DMM while the PCM connectors remain
connected.
Engine Controls Information
The driveability and emissions information describes the function and operation of the powertrain
control module (PCM).
The engine controls Information contains the following:
^ Component locations
^ Wiring diagrams
^ PCM terminal end view and terminal definitions
^ Diagnostic System Check-Computers and Controls Systems
^ Diagnostic trouble code (DTC) tables
The component system includes the following items:
^ Component and circuit description
^ On-vehicle service for each sub-system
^ Functional checks and diagnostic tables
The DTCs also contain diagnostic support information containing circuit diagrams, circuit or system
information, and helpful diagnostic information.
System Status and Drive Cycle For Inspection/Maintenance
The System Status selection is included in the scan tool System Info menu.
Several states require that the I/M (OBD II system) pass on-board tests for the major diagnostics
prior to having a vehicle emission inspection. This is
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also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the System Status, complete or not complete, in
order to verify that the vehicle meets the criteria to comply with local area requirements. Using the
System Status display, any of the following systems or combination of systems may be monitored
for I/M Readiness:
^ The catalyst
^ The Evaporative Emission (EVAP) system
^ The Heated Oxygen Sensors (HO2S)
^ The HO2S heater
^ The Exhaust Gas Recirculation (EGR) system
^ The secondary air injection (AIR) system
IMPORTANT: The System Status display indicates only whether or not the test has been
completed. The System Status display does not necessarily mean that the test has passed. If a
Failed Last Test indication is present for a DTC associated with one of the above systems,
diagnosis and repair is necessary in order to meet the I/M requirement. Verify that the vehicle
passes all of the diagnostic tests associated with the displayed System Status prior to returning the
vehicle to the customer. Refer to the Typical Drive Cycle table, more than one drive cycle may be
needed, to use as a guide to complete the I/M System Status tests.
Typical Drive Cycle
Following a DTC info clear, System Status clears for one or all of these systems. Following a
battery disconnect or a PCM replacement, all System Status information clears.
Primary System Based Diagnostics
There are primary system-based diagnostics which evaluate the system operation and their effect
on vehicle emissions. The primary system-based diagnostics are listed below, with a brief
description of the diagnostic functionality.
Oxygen Sensor Diagnosis
Diagnose the fuel control heated oxygen sensors (HO2S) for the following conditions:
^ Heater performance, heater current monitor
^ Response switches, number or switches R/L or L/R
^ Response time, time to switch R/L or L/R
^ Inactive signal, output steady at bias voltage - approximately 450 mV
^ Signal fixed high
^ Signal fixed low
Diagnose the catalyst monitor HO2S for the following functions:
^ Heater performance, heater current monitor
^ Signal fixed low
^ Signal fixed high
^ Inactive sensor
Heated Oxygen Sensors
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases.
The PCM uses the signal voltage from the fuel control HO2S in a Closed Loop in order to adjust
the fuel injector pulse width. While in a Closed Loop, the PCM can adjust fuel delivery in order to
maintain an air to fuel ratio which allows the best combination of emission control and driveability.
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If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Catalyst Monitor Heated Oxygen Sensors
In order to control emissions of HydroCarbons (HC), Carbon Monoxide (CO), and Oxides Of
Nitrogen (NOx), the system uses a TWC. The catalyst promotes a chemical reaction which oxidizes
the HC and CO present in the exhaust gas, converting the HC and CO into harmless water vapor
and carbon dioxide. The catalyst also converts NOx to nitrogen. Catalyst monitor HO2S,
post-catalyst HO2S, are always located downstream of the catalytic converter.
The PCM has the ability to monitor this process using the post catalyst HO2S. The pre-sensors
produce an output signal which indicates the amount of oxygen present in the exhaust gas entering
the TWC. The post sensor produces an output signal which indicates the oxygen storage capacity
of the catalyst. This in turn indicates the catalysts ability to convert exhaust gases efficiently. If the
catalyst is operating efficiently, the pre-HO2S signal is far more active than that produced by the
post-HO2S.
In addition to catalyst monitoring, the post-HO2S has a limited role in controlling fuel delivery. If the
post-HO2S signal indicates a high or low oxygen content for an extended period of time while in a
Closed Loop, the PCM adjusts the fuel delivery slightly in order to compensate.
Catalyst Monitor Diagnostic Operation
The catalyst monitor diagnostic measures oxygen storage capacity of the catalyst converter. In
order to do this, the HO2S are installed before and after the TWC. Voltage variations between the
sensors allow the PCM to determine the catalyst emission performance.
As a catalyst becomes less effective in promoting chemical reactions, the catalysts capacity to
store and release oxygen generally degrades. The catalyst monitor diagnostic is based on a
correlation between conversion efficiency and oxygen storage capacity.
A good catalyst, e.g. 95 percent hydrocarbon conversion efficiency, shows a relatively flat output
voltage on the post-catalyst HO2S. A degraded catalyst, 65 percent hydrocarbon conversion,
shows a greatly increased activity in output voltage from the post catalyst HO2S.
The post-catalyst HO2S is used to measure the oxygen storage and release capacity of the
catalyst. A high oxygen storage capacity indicates a good catalyst. Low oxygen storage capacity
indicates a failing catalyst. The TWC and the HO2S must be at operating temperature in order to
achieve correct oxygen sensor voltages like those shown in the post-catalyst HO2S outputs
graphic.
The catalyst monitor diagnostic is sensitive to the following conditions:
^ Exhaust leaks
^ HO2S contamination
^ Alternative fuels
Exhaust system leaks may cause the following:
^ Prevent a degraded catalyst from failing the diagnostic
^ Cause a false failure for a normally functioning catalyst
^ Prevent the diagnostic from running
Some of the contaminants that may be encountered are phosphorus, lead, silica, and sulfur. The
presence of these contaminants prevent the TWC diagnostic from functioning properly.
Three-Way Catalyst Oxygen Storage Capacity
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Three-Way Catalyst Oxygen Storage Capacity
The PCM must monitor the TWC system for efficiency. In order to accomplish this, the PCM
monitors the pre-catalyst and post-catalyst HO2S. When the TWC is operating properly, the
post-catalyst (2) HO2S shows significantly less activity than the pre-catalyst (1) HO2S. The TWC
stores oxygen during the normal reduction and oxidation process. The TWC releases oxygen
during the normal reduction and oxidation process. The PCM calculates the oxygen storage
capacity using the difference between the pre-catalyst and post-catalyst HO2S voltage levels.
Whenever the sensor activity of the post-catalyst (2) HO2S nears the sensor activity of the
pre-catalyst (1) HO2S, the catalysts efficiency is degraded. Aftermarket HO2S characteristics may
be different from the original equipment manufacturer sensor. This may lead to a false pass or a
false fail of the catalyst monitor diagnostic. Similarly, if an aftermarket catalyst does not contain the
same amount of precious metal content as the original part, the correlation between oxygen
storage and conversion efficiency may be altered enough to set a false DTC.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft rotational velocity, aka reference period,
variations. The PCM determines crankshaft rotational velocity using the Crankshaft Position (CKP)
Sensor and Camshaft Position (CMP) Sensor. When a cylinder misfires, the crankshaft slows down
momentarily. By monitoring the crankshaft and CMP sensor signals, the PCM can calculate when a
misfire occurs.
For a non-catalyst damaging misfire, the diagnostic is required to monitor a misfire present for
between 1,000-3,200 engine revolutions.
For catalyst damage misfire, the diagnostic responds to the misfire within 200 engine revolutions
Rough roads may cause false misfire detection. A rough road applies sudden torque variations to
the drive wheels and drivetrain. This torque can intermittently decrease the crankshaft rotational
velocity. The Antilock Braking (ABS) System detects uneven speed between the vehicles wheels
and sends data via the serial data bus to the PCM to disable the misfire monitor until the rough
road is no longer detected.
On automatic transmission equipped vehicles, the Torque Converter Clutch (TCC) disables
whenever a misfire is detected. Disabling the TCC isolates the engine from the rest of the drive line
and minimizes the affect of the drive wheel inputs on crankshaft rotation.
When the TCC has disabled as a result of misfire detection, the TCC is re-enabled after
approximately 3,200 engine revolutions if no misfire is detected. The TCC remains disabled
whenever the misfire is detected, with or without a DTC set. This allows the misfire diagnostic to
reevaluate the system.
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Whenever a cylinder misfires, the misfire diagnostic counts the misfire and notes the crankshaft
position at the time the misfire occurred.
A current and a history misfire counter is maintained for each cylinder. The misfire current
counters, Misfire Cur #1-8, indicate the number of firing events out of the last 200 cylinder firing
events which were misfires. The misfire current counters displays real time data without a misfire
DTC stored. The misfire history counters, Misfire Hist #1-8, indicate the total number of cylinder
firing events which were misfires. The misfire history counters display 0 until the misfire diagnostic
has failed and a DTC P0300 is set. Once the misfire DTC sets, the misfire history counters will be
updated every 200 cylinder firing events. The Misfire counters graphic illustrates how these misfire
counters are maintained.
When crankshaft rotation is erratic, the PCM detects a misfire condition. Because of this erratic
condition, the data that is collected by the diagnostic can sometimes incorrectly identify which
cylinder is misfiring. The Misfire Counters graphic shows there are misfires counted from more than
one cylinder. Cylinder #1 has the majority of counted misfires. In this case, the misfire counters
would identify cylinder #1 as the misfiring cylinder. The misfires in the other counters were just
background noise caused by the erratic rotation of the crankshaft. If the number of accumulated
misfires is sufficient for the diagnostic to identify a true misfire, the diagnostic will set DTC
P0300-Misfire Detected. The illustration depicts an accumulation in the history buffers.
If two cylinders in sequential tiring order are both misfiring, the first misfiring cylinder will
accumulate misfires in the cylinder buffer, but the second misfiring cylinder will not. This is because
the PCM compares a misfiring cylinder with the cylinder 90 degrees prior to that cylinder in the
firing order. Therefore the PCM would be comparing crankshaft speed of the second misfiring
cylinder to an already suspect cylinder. The PCM however, will be able to detect both misfiring
cylinders after the engine exceeds 2,000 RPM. This is because the PCM then starts to compare
misfires to the opposing cylinder rather than the previous cylinder in the firing order.
Use Techline equipment to monitor the misfire counter data on applicable vehicles. Knowing which
specific cylinders misfire can lead to the root cause. Using the information in the misfire counters
identifies which cylinders are misfiring. If the counters indicate cylinders number 1 and 4 misfired,
look for a circuit or component common to both cylinders.
The misfire diagnostic may indicate a fault due to a temporary fault not necessarily caused by a
vehicle emission system malfunction. Examples include the following items:
^ Contaminated fuel
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^ Running out of fuel
^ Fuel fouled spark plugs
^ Basic engine fault
Fuel Trim System Operation
The fuel trim system monitors the averages of short-term and long-term fuel trim values. If these
fuel trim values stay at the individual limits for a calibrated period of time, a malfunction is indicated.
The fuel trim diagnostic compares the average of short and long-term fuel trim values. If either
value is within the thresholds, a pass is recorded. If either value is outside the thresholds, a rich or
lean fuel trim DTC will set.
Comprehensive Component Monitor Diagnostic
Comprehensive component monitoring diagnostics are required to monitor emissions-related input
and output powertrain components.
Input Components The PCM monitors the input components for circuit continuity and out-of-range
values. This includes performance checking. Performance checking refers to indicating a fault
when the signal from a sensor does not seem reasonable, such as a Throttle Position (TP) sensor
that indicates high throttle position at low engine loads or manifold Absolute Pressure (MAP)
Voltage. The input components may include, but are not limited to, the following sensors: ^
The Vehicle Speed (VSS) Sensor
^ The Mass Air Flow (MAF) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Crankshaft Position (CKP) Sensor
^ The Knock Sensor (KS)
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Camshaft Position (CMP) Sensor
^ The Manifold Absolute Pressure (MAP) Sensor
In addition to the circuit continuity and rationality check, the engine coolant temperature (ECT)
sensor is monitored for the sensors ability to achieve a steady state temperature to enable Closed
Loop fuel control.
Output Components Diagnose the output components for the proper response to PCM commands.
Components where functional monitoring is not feasible will be monitored for circuit continuity and
out-of-range values if applicable.
Output components to be monitored include, but are not limited to, the following circuits: ^
The Idle Air Control (IAC) Motor
^ The Evaporative Emission (EVAP) System
^ The electronic transmission controls
^ The A/C relay, if equipped
^ The VSS output
^ The Malfunction Indicator Lamp (MIL) Control
^ The cruise control enable, if equipped
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Powertrain Control Module (PCM) Programming (Off-board)
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(Off-board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: ^
DO NOT program a control module unless you are directed by a service procedure or you are
directed by a General Motors Corporation service bulletin. Programming a control module at any
other time will not permanently correct a customer's concern.
^ The Off-Board Programming is used in situations where a control module must be programmed
without having the vehicle present. The Off-Board Programming Adapter must be used to perform
the Off-Board Programming procedure. The adapter allows the control module to power up and
allows the Tech 2 to communicate with the control module.
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
Ensure that all connections are secure at the following locations: ^
The Off-Board Programming Adapter
^ The Tech 2
^ The control module
^ The Techline terminal
OFF-BOARD PROGRAMMING
1. Obtain the VIN of the vehicle for which the control module is being programmed. 2. With the
Techline terminal, select Service Programming. 3. Select Tech 2, Reprogram ECU, and Off-Board
Programming Adapter as the ECU location. 4. Connect the control module, Off-Board
Programming Adapter, and the Tech 2 as described on the Techline terminal. Ensure you use the
correct
harness connector from the Off-Board Programming Adapter kit.
5. With the Tech 2, select Service Programming Request Information function. The Tech 2
communicates with the control module and receives the
access code.
6. With the Tech 2, exit the Service Programming Request Information. 7. Disconnect the Tech 2
from the Off-Board Programming Adapter. 8. Connect the Tech 2 to the Techline terminal. 9. Turn
ON the Tech 2.
10. With the Techline terminal, enter the VIN of the vehicle that will be receiving the control module.
11. The Techline terminal will display the message, attaching to database. 12. Identify what type of
programming that you are performing. 13. Select the appropriate calibration file. 14. Ensure all
connections are secure. 15. The Techline terminal displays a summary screen that summarizes
your selections. After confirming you choices, the Techline terminal
automatically loads the calibration files to the Tech 2.
16. After the download is complete, turn OFF the Tech 2. 17. Disconnect the Tech 2 from the
Techline terminal. 18. Connect the Tech 2 to the Off-Board Programming Adapter. 19. With the
Tech 2, select Service Programming.
IMPORTANT: DO NOT turn OFF the Off-Board Programming Adapter if the programming
procedure is interrupted or unsuccessful. Ensure the control module and the Off-Board
Programming Adapter connections are secure and the Techline operating software is up to date.
Attempt to reprogram the control module. If the control module cannot be programmed, replace the
control module.
20. With the Tech 2, select Program. 21. After the download is complete, exit Service
Programming. 22. Turn OFF the Off-Board Programming Adapter.
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Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(On-Board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: DO NOT program a control module unless you are directed by a service procedure
or you are directed by a General Motors Corporation service bulletin. Programming a control
module at any other time will not permanently correct a customers concern.
Ensure the following conditions are met before programming a control module: ^
Vehicle system voltage There is no charging system concern. All charging system concerns must be repaired before
programming a control module.
- Battery voltage is greater than 12 volts but less than 16 volts. The battery must be charged before
programming the control module if the battery voltage is low.
- A battery charger is NOT connected to the vehicle's battery. Incorrect system voltage or voltage
fluctuations from a battery charger, may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicle's battery. ^
Twilight sentinel
^ Interior lights
^ Daytime running lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system. Refer to the Owners manual.
^ HVAC systems
^ Cooling System fans, etc.
^ The ignition is in the proper position. The scan tool prompts you to turn ON the ignition, with the
engine OFF. DO NOT change the position of the ignition switch during the programming procedure,
unless instructed to do so.
^ All tool connections are secure. RS-232
- The connection at the DLC is secure.
- Voltage supply circuits
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
REMOTE PROGRAMMING
1. Turn OFF the ignition. 2. Install the Tech 2 to the data link connector (DLC). 3. Turn ON the
ignition, with the engine OFF. 4. Turn OFF all vehicle accessories. 5. With the Tech 2, select
Service Programming. 6. Identify vehicle information as requested by the Tech 2. 7. Select the type
of module you are programming. 8. Select the type of programming to be performed. 9. Verify the
displayed VIN with the vehicle VIN. If the displayed VIN does not match the actual VIN, write down
the actual VIN and correct the
VIN at the Techline terminal.
10. When complete, Exit Service Programming. 11. Turn OFF the Tech 2 and disconnect the Tech
2 from the vehicle. 12. Turn OFF the ignition. 13. Connect the Tech 2 to the Techline terminal. 14.
Select Service Programming. 15. Select Tech 2 as the tool you are using. 16. Select the type of
programming to be performed. 17. Verify the displayed VIN with the vehicle VIN. Correct the VIN
as necessary. 18. Select the type of module you are programming. 19. Identify what type of
programming that you are performing.
^ Normal-This type of programming is for updating an existing calibration or programming a new
controller.
^ Vehicle configuration index (VCI)-This selection is used if the vehicle VIN is unavailable or not
recognized by the Techline terminal. Observe, you will need to contact the Techline Customer
Support center to use this option.
^ Reconfigure-This is to reconfigure a vehicle, such as tire size and axle ratio changes.
20. Select the appropriate calibration file. 21. Ensure all connections are secure. 22. Select Reprog
to initiate the download of the new calibration to the Tech 2. 23. After the download is complete,
turn OFF the Tech 2. 24. Disconnect the Tech 2 from the Techline terminal. 25. Install the Tech 2
to the data link connector (DLC). 26. Turn ON the Tech 2. 27. Turn ON the ignition, with the engine
OFF. 28. Select Service Programming.
IMPORTANT: DO NOT turn OFF the ignition if the programming procedure is interrupted or
unsuccessful. Ensure that all the PCM and DLC
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connections are secure and the Techline(TM) operating software is up to date. Attempt to
reprogram the control module. If the control module cannot be programmed, replace the control
module. Refer to Powertrain Control Module (PCM) Replacement.
29. Select Program. 30. After the download is complete, EXIT Service Programming. 31. Turn OFF
the ignition for 30 seconds. 32. Turn OFF the Tech 2. 33. If a control module is replaced the
following service procedures must be performed:
^ CKP System Variation Learn Procedure
^ Inspection/Maintenance (I/M) Complete System Set Procedure
^ Programming Theft Deterrent System Components
PROGRAMMING VERIFICATION
1. With a scan tool, clear the DTCs. 2. Attempt to start the engine. 3. Repeat the Service
Programming procedure if the engine does not start or operates poorly. Perform the following
procedures before programming
the PCM: ^
Ensure the control module and DLC connections are OK.
^ Ensure the Techline operating software is up to date.
^ Ensure the calibration part number is correct for the vehicle.
4. Attempt to program the control module. If the control module still cannot be programmed
properly, replace the control module. Refer to
Powertrain Control Module (PCM) Replacement. You must program the replacement control
module.
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Engine Control Module: Service and Repair Powertrain Control Module (PCM) Replacement
Service of the powertrain control module (PCM) should normally consist of either replacement of
the PCM or electrically erasable programmable read only memory (EEPROM) programming. If the
diagnostic procedures call for the PCM to be replaced, the PCM should be inspected first to see if
the correct part is being used. If the correct part is being used, remove the faulty PCM and install
the new service PCM.
IMPORTANT: To prevent internal PCM damage, the ignition must be OFF when disconnecting or
reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail,
PCM fuse, or jumper cables. ^
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM
module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are
installed correctly. The gaskets prevent contaminant intrusion into the PCM.
^ The replacement PCM must be programmed
Removal Procedure
1. Release the PCM cover mounting holes (1,5) away from the mounting tabs on the PCM
mounting bracket. 2. Release the PCM cover (8) from the mounting bracket. 3. Remove the PCM
cover.
NOTE: ^
Refer to PCM and ESD Notice in Service Precautions.
^ In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or
reconnecting the PCM connector.
4. Disconnect the PCM harness connectors (6). 5. Release the spring latch (2) from the PCM. 6.
Release the PCM mounting tabs (3) from the PCM. 7. Remove the PCM (4) from the engine
compartment.
Installation Procedure
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1. Install the PCM (4) to the PCM mounting bracket (7) ensuring that the mounting tabs (3) are
engaged. 2. Secure the spring latch (2) to the PCM.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Connect the PCM connectors (6) to the PCM (4).
Tighten Tighten the PCM connector end fasteners to 8 N.m (71 lb in).
4. Install the PCM cover (8) to the PCM mounting bracket (7), ensuring the mounting tabs on the
PCM mounting bracket are engaged into the
mounting holes in the PCM cover.
5. If a new PCM is being installed, program the PCM. See: Testing and Inspection/Programming
and Relearning
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Engine Control Module: Service and Repair Service Programming System (SPS)
The Service Programming System (SPS) allows a technician to program a control module through
the Data Link Connector (DLC). The information transfer circuit that is used at the DLC is the same
serial data circuit used by the scan tool for retrieving Diagnostic Trouble Codes (DTCs), displaying
data, clearing DTCs, etc. This procedure offers the ability to install software/calibrations matched to
a particular vehicle.
Most control modules have 2 types of memory. The software/calibrations reside in the flash
memory. The two types of memory are listed below:
^ Electrically Erasable Programmable Read Only Memory (EEPROM)
This type of memory allows selected portions of memory to be programmed while other portions
remain unchanged.
Certain learned values reside in the EEPROM, such as: ^
The Vehicle Identification Number (VIN)
^ The crankshaft variation learned position
^ The software/calibrations identification numbers
^ The control module security information
^ Flash Read Only Memory - Flash Memory
^ Flash memory has increased memory storage capacity. During programming, all information
within this type of memory is erased, and then replaced with entirely new information.
Service Programming Methods The 4 methods of programming a control module and the proper
tools for each method are as follows: ^
Remote Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle
^ Pass Thru Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle.
^ Off-Board Remote Programming, vehicle NOT available: The Tech 2 or other scan tool, Off-board Programming Adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
^ Off-Board Pass Thru Programming -
The Tech 2 or other scan tool, off-board programming adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
Before Programming A Control Module
IMPORTANT: DO NOT program an existing control module with the identical software/calibration
package. This procedure is not a short cut to correct a driveability condition. This is an ineffective
repair. A control module should only be programmed when the following occurs: ^
When a service procedure instructs you to replace the control module. The service part control
module does not contain operating software or calibrations.
^ General Motors Corporation releases an updated software/calibration package.
Ensure that the following conditions are met before programming a control module: ^
Vehicle system voltage: There are no charging system concerns. All charging system concerns must be repaired before
programming a control module.
- The battery voltage is greater than 12 volts but less than 16 volts. The battery must be fully
charged before programming the control module.
- A battery charger is NOT connected to the vehicles battery. Incorrect system voltage or voltage
fluctuations from a battery charger may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicles battery. Turn OFF or disable
systems such as: ^
Daytime Running Lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system.
^ Heating, Ventilation, And Air Conditioning (HVAC) systems
^ Engine cooling fans, etc
^ The ignition switch is in the proper position. The scan tool prompts you to turn ON the ignition,
with the engine OFF. DO NOT change the position of the ignition switch during the programming
procedure unless instructed to do so.
^ All tool connections are secure: The RS-232 cable
- The connection at the DLC
- The voltage supply circuits
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Powertrain Control Module (PCM) Programming (Off-board) > Page 940
- The OBPA
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
^ If you are performing the pass-through programming procedure using a notebook computer
without the power cord, ensure that the internal battery is fully charged.
After Programming a Control Module The powertrain may operate slightly different after a control
module software/calibration update. Operating the powertrain through various driving conditions
allows the control module to re-learn certain values. The control module must re-learn the following
after a software/calibration update: ^
Fuel trim correction
^ Idle Air Control (IAC) learned position
^ Automatic transmission shift adapts
Other learned values only re-learn by performing a service procedure.
If a control module is replaced the following service procedures may need to be performed: ^
The crankshaft variation learn procedure
^ The engine oil life reset procedure
^ The idle learn procedure
^ The inspection/maintenance complete system set procedure
^ The vehicle theft deterrent password learn procedure
^ The Throttle Position (TP) sensor learn procedure
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Locations > Fuel Pump Relay
Fuel Pump Relay: Locations Fuel Pump Relay
FUEL PUMP RELAY
Fuse Block - Underhood
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Page 946
Locations View
The Fuel Pump (FP) Relay is located in the Underhood Fuse Block. The Underhood Fuse Block is
located at the left side of the engine compartment near the battery.
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Page 947
Fuel Pump Relay: Locations Fuel Pump Relay Secondary - With Dual Tanks
SECONDARY FUEL PUMP RELAY (With Dual Tanks Only)
Locations View
The Secondary Fuel Pump (FP) Relay (1) is attached to the Underhood Fuse Block on bracket.
The Underhood Fuse Block is located at the left side of the engine compartment near the battery.
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Page 948
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
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and Instructions
Fuel Pump Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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and Instructions > Page 951
Electrical Symbols Part 1
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and Instructions > Page 952
Electrical Symbols Part 2
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and Instructions > Page 953
Electrical Symbols Part 3
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Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 954
Electrical Symbols Part 4
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and Instructions > Page 955
Fuel Pump Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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and Instructions > Page 956
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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and Instructions > Page 965
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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and Instructions > Page 966
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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and Instructions > Page 967
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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and Instructions > Page 969
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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and Instructions > Page 974
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 976
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 977
Equivalents - Decimal And Metric Part 1
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 978
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 979
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 980
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information
and Instructions > Page 981
Fuel Pump (FP) Relay-Secondary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Ignition System > Ignition Relay > Component Information > Locations
Ignition Relay: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Ignition System > Ignition Relay > Component Information > Locations > Page 986
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Ignition System > Ignition Relay > Component Information > Locations > Page 987
Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTION
The ignition relay supplies battery positive voltage to the following components: ^
The fuel injectors
^ The ignition coils
^ The powertrain control module (PCM)
^ The throttle actuator control (TAC) module
DIAGNOSTIC AIDS
The following will occur if the ignition relay fails to close: ^
The engine cranks, but does not run.
^ Scan tool data will be available.
^ Instrument panel lights will illuminate.
TEST DESCRIPTION
Steps 1-5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Powertrain Management > Relays and
Modules - Ignition System > Ignition Relay > Component Information > Locations > Page 988
Steps 6-11
The numbers below refer to the step numbers on the diagnostic table. 2. This step is testing the
battery positive voltage circuit of the ignition relay. 3. This step is testing the ignition 1 positive
voltage circuit of the ignition relay. 4. This step is testing the coil ground circuit of the ignition relay.
5. This step isolates the circuits from the ignition relay. All of the circuits at the relay are good if the
test lamp illuminates.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations
Starter Relay: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations > Page 993
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations > Page 994
Starter Relay: Service and Repair
REMOVAL PROCEDURE
1. Remove the underhood bussed electrical center (UBEC) cover. 2. Remove the starter motor
relay.
INSTALLATION PROCEDURE
1. Install the starter motor relay. 2. Install the underhood bussed electrical center (UBEC) cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Specifications
Suspension Control Module: Specifications
Electronic Suspension Control Module to Bracket
.............................................................................................................................. 1.6 Nm (14 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 1002
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 1003
Suspension Control Module: Diagrams C3
Suspension Control Module - C3
Part 1 of 2
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 1004
Part 2 of 2
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > Page 1005
Suspension Control Module: Service and Repair
Electronic Suspension Control Module Replacement (Tahoe/Yukon/Escalade)
Removal Procedure
1. Remove the right side interior trim panel. 2. Disconnect the electrical connectors from the
module.
3. Remove the screw. 4. Slide the module from the bracket and remove the module from the
vehicle.
Installation Procedure
1. Install the module to the vehicle by sliding the module into the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the screw.
Tighten the screw to 1.6 Nm (14 inch lbs.).
3. Connect the electrical connectors to the module. 4. If you are replacing the module you must
recalibrate the module by performing the following procedure:
^ Connect the scan tool to the Data Line Connector (DLC).
^ Turn the ignition ON with the engine OFF.
^ Proceed per the instructions on the scan tool readout.
5. Install the right side interior trim panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Steering and Suspension > Relays and
Modules - Wheels and Tires > Tire Pressure Monitor Receiver / Transponder > Component Information > Technical Service
Bulletins > Tire Monitor System - TPM Sensor Information
Tire Pressure Monitor Receiver / Transponder: Technical Service Bulletins Tire Monitor System TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Technical Service Bulletins >
Drivetrain - Transfer Case Control Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Technical Service Bulletins >
Drivetrain - Transfer Case Control Module Replacement > Page 1017
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1 > Page 1020
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1 > Page 1021
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 1022
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 1023
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Transmission and Drivetrain > Relays and
Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 1024
10. Start the engine and test the automatic transfer case system for proper shift operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Heated Glass Element
Relay > Component Information > Locations
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Rear Defogger Relay >
Component Information > Locations
Rear Defogger Relay: Locations
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Rear Defogger Relay >
Component Information > Locations > Page 1032
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Power Window Control
Module > Component Information > Service and Repair > Module Replacement - Rear Power Window
Power Window Control Module: Service and Repair Module Replacement - Rear Power Window
REMOVAL PROCEDURE
1. Remove the trim panel. 2. Remove the water deflector. 3. Remove the window glass. 4. Remove
the window sash. 5. Remove the glass weatherstrip. 6. Remove the module from the door.
INSTALLATION PROCEDURE
1. Install the module to the door. 2. Install the glass weatherstrip. 3. Install the window sash. 4.
Install the window glass. 5. Install the water deflector. 6. Install the trim panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Power Window Control
Module > Component Information > Service and Repair > Module Replacement - Rear Power Window > Page 1037
Power Window Control Module: Service and Repair Module Replacement - Front Power Window
REMOVAL PROCEDURE
1. Raise and support the window glass. 2. Remove the trim panel. 3. Remove the water deflector.
4. Disconnect the harness from the electric window motor assembly. 5. Remove the 2 bolts that
hold the window glass to the regulator. 6. Remove the bolts from the window regulator. 7. Remove
the window regulator assembly from the door by folding both sides of the window regulator
assembly together.
INSTALLATION PROCEDURE
1. Install the regulator to the door.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the bolts to the window regulator.
Tighten Tighten the bolts to 9 N.m (80 lb in).
3. Align the window glass to the regulator, and install the bolts that hold the window glass to the
regulator.
Tighten Tighten the bolts to 9 N.m (80 lb in).
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Chevrolet Workshop Manuals > Relays and Modules > Relays and Modules - Windows and Glass > Power Window Control
Module > Component Information > Service and Repair > Module Replacement - Rear Power Window > Page 1038
4. Connect the harness to the electric window motor assembly. 5. Install the water deflector. 6.
Install the trim panel. 7. Lower the window. Inspect the operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Lock Cylinder Switch > Component Information > Diagrams
Passlock Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams
Parking Assist Distance Sensor: Diagrams
Object Sensor - LR Corner
Object Sensor - RR Corner
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1047
Object Sensor - LR Middle
Object Sensor - RR Middle
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1048
Parking Assist Distance Sensor: Service and Repair
REAR OBJECT SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Disconnect the electrical connectors to the rear object sensor.
2. Lift the locking tabs on the housing (4) and remove the rear object sensor (1).
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1049
3. Insert a small size screw driver at (3) to release the tabs in order to remove the spring (1).
4. From the inside of the housing push in the tabs and remove.
5. Remove the bezel by pushing it through the fascia.
INSTALLATION PROCEDURE
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1050
IMPORTANT: Do not paint the sensor.
1. Paint the sensor bezel to match the color of the bumper fascia.
2. Align the keyhole (2) with the key (1) and press the sensor bezel into the fascia.
3. Install the housing to the bezel through the back side of the fascia. The housing snaps into the
cutouts on the bezel.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1051
IMPORTANT: The spring keys must be on the top and bottom of the housing.
4. Install the spring (1) to the housing (2) until fully seated.
Ensure the sensor is held to the bumper fascia firmly.
5. Install the decoupling ring (2) to the sensor (1). 6. Insert the sensor into the housing (4) with the
connector pointing toward the passenger side of the fascia. The sensor tabs snap into the cutouts
on
the housing (4).
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Distance Sensor > Component Information > Diagrams > Page 1052
7. Connect the electrical connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Switch > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Switch > Component Information > Locations > Page 1056
Rear Parking Assist (RPA) Disable Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Parking Assist Switch > Component Information > Locations > Page 1057
Parking Assist Switch: Service and Repair
REAR OBJECT ALARM MODULE SWITCH REPLACEMENT
REMOVAL PROCEDURE
1. Remove the dash trim bezel. 2. Grasp the buttons assembly (2) housing and pull outwards. 3.
Disconnect the electrical connector from the rear object alarm module switch. 4. Remove the
switch (1) from the housing (2).
INSTALLATION PROCEDURE
1. Install the rear object alarm switch into the housing (2). 2. Connect the electrical connector to the
switch (1). 3. Install the switch housing into the dash. 4. Install the dash trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Accessories and Optional Equipment >
Remote Switch, Audio - Stereo > Component Information > Technical Service Bulletins > Audio - Inadvertent Steering
Wheel Button Activation
Remote Switch: Technical Service Bulletins Audio - Inadvertent Steering Wheel Button Activation
INFORMATION
Bulletin No.: 08-08-44-028
Date: August 28, 2008
Subject: Information On Inadvertent Steering Wheel Control (SWC) Button Press Causing Radio
Anomalies
Models: 2009 and Prior GM Passenger Cars and Trucks (Including Saturn) 2009 and Prior
HUMMER H2, H3 Models 2009 and Prior Saab 9-7X
All Vehicles with Steering Wheel Controls
This bulletin is being issued to provide a recommendation for vehicles with a customer concern of
the radio station tuning changing by itself, volume changing by itself, radio changing by itself, or
radio muting or going silent when driving and turning the steering wheel.
The switches on the right hand side of the steering wheel are easily pressed and may inadvertently
be pressed when turning the steering wheel.
These concerns may be affected by the location of the steering wheel controls.
Recommendation
Do Not Replace The Radio
1. Please determine that the switch controls on the steering wheel are functioning correctly.
2. Ask the customer if their hand was in close proximity to the steering wheel controls when the
condition happened. Explain to the customer that bumping the controls would have caused this
undesired action. Explain to the customer the proper use and function of the steering wheel
controls.
Disclaimer
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Underhood Lamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Underhood Lamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1081
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1082
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1083
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1084
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1085
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1086
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1087
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1088
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1089
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1090
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1091
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1092
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1093
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1094
Equivalents - Decimal And Metric Part 1
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> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1095
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1096
Various symbols are used in order to describe different service operations.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Hood Switch / Sensor
> Underhood Lamp Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1097
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Door Lock
Switch > Component Information > Diagrams > Door Lock Switch - Driver/Front Passenger
Door Lock Switch - Driver/Front Passenger
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Door Lock
Switch > Component Information > Diagrams > Door Lock Switch - Driver/Front Passenger > Page 1102
Window/Door Lock Switch - Front Passenger
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Door Lock
Switch > Component Information > Service and Repair > Power Door Lock Switch Replacement - Front
Power Door Lock Switch: Service and Repair Power Door Lock Switch Replacement - Front
REMOVAL PROCEDURE
1. Remove the power accessory switch panel. 2. Disconnect the electrical connector from the door
lock switch. 3. Remove the screws from the door lock switch. 4. Remove the power window and
door lock switch from the switch panel.
INSTALLATION PROCEDURE
1. Install the power door lock and power window switch assembly to the switch panel, sliding the
front tabs in first. Rock the switch down in order to
seat the door lock switch completely.
2. Install the screws to the door lock switch. 3. Connect the electrical connector to the door lock
switch. 4. Install the power accessory switch plate.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Door Lock
Switch > Component Information > Service and Repair > Power Door Lock Switch Replacement - Front > Page 1105
Power Door Lock Switch: Service and Repair Power Door Lock Switch Replacement - Rear
REMOVAL PROCEDURE
1. Remove the upper garnish molding. 2. Remove the D-Pillar molding. 3. Disconnect the electrical
connectors.
4. Push on the tab (2) in order to remove the switch from the D-Pillar molding. 5. Insert a small
screwdriver between the tab (1) in order to pry out the switch from the case.
INSTALLATION PROCEDURE
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Switch > Component Information > Service and Repair > Power Door Lock Switch Replacement - Front > Page 1106
1. Install the switch into the case by pushing until the tab (1) locks into place. 2. Install the switch
assembly into the D-Pillar molding. 3. Connect the electrical connectors.
4. Install the D-Pillar molding to vehicle. 5. Install the upper garnish molding to vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Mirror Switch >
Component Information > Service and Repair > Power Mirror Switch Replacement
Power Mirror Switch: Service and Repair Power Mirror Switch Replacement
REMOVAL PROCEDURE
1. Remove the power accessory switch panel. 2. Remove the power mirror switch from the
accessory switch panel using a flat-bladed tool in order to release the retainer tabs.
INSTALLATION PROCEDURE
1. Install the power mirror switch, pressing the switch into place until fully seated. 2. Install the
power accessory switch panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Mirror Switch >
Component Information > Service and Repair > Power Mirror Switch Replacement > Page 1111
Power Mirror Switch: Service and Repair Power Folding Outside Mirror Switch Replacement
REMOVAL PROCEDURE
1. Remove the instrument panel (IP) bezel. 2. Release the plastic retaining clips using a flat-bladed
tool in order to remove the power folding mirror switch. 3. Disconnect the electrical connectors. 4.
Remove the power folding mirror switch from the IP accessory housing.
INSTALLATION PROCEDURE
1. Connect the electrical connectors. 2. Install the power folding mirror switch to the IP accessory
housing. 3. Push in the power folding mirror switch until the switch snaps into position. 4. Install the
power accessory switch panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Motor
Position Sensor > Component Information > Diagrams > Seat Recliner Motor Position Sensor - Driver
Seat Recliner Motor Position Sensor - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Motor
Position Sensor > Component Information > Diagrams > Seat Recliner Motor Position Sensor - Driver > Page 1116
Seat Front Vertical Motor Position Sensor - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Motor
Position Sensor > Component Information > Diagrams > Seat Recliner Motor Position Sensor - Driver > Page 1117
Seat Horizontal Motor Position Sensor - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Motor
Position Sensor > Component Information > Diagrams > Seat Recliner Motor Position Sensor - Driver > Page 1118
Seat Rear Vertical Motor Position Sensor - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Technical Service Bulletins > Customer Interest for Power Seat Switch: > 05-08-50-017 > Dec >
05 > Interior - Power Seat Switch Knobs Loose/Missing
Power Seat Switch: Customer Interest Interior - Power Seat Switch Knobs Loose/Missing
Bulletin No.: 05-08-50-017
Date: December 14, 2005
TECHNICAL
Subject: Power Front Seat (RPO AN3) Switch Knobs Loose or Missing (Replace Switch Knobs)
Models: 2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV
2002-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe 2002-2006 GMC Sierra, Yukon,
Yukon XL
with Individual Front Seat Non-Bucket (RPO AN3) and Driver Front Seat Power Adjuster (AG1)
and/or Passenger Front Seat Power Adjuster (AG2)
Condition
Some customers may comment that the power front seat adjuster switch knobs are loose and fall
off or are missing.
Correction
Replace the front seat adjuster switch knob. These knobs were formerly available only as part of
the power seat adjuster switch. DO NOT replace the switch if the knob only needs to be replaced.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Technical Service Bulletins > Customer Interest for Power Seat Switch: > 05-08-50-017 > Dec >
05 > Interior - Power Seat Switch Knobs Loose/Missing > Page 1127
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Power Seat Switch: >
05-08-50-017 > Dec > 05 > Interior - Power Seat Switch Knobs Loose/Missing
Power Seat Switch: All Technical Service Bulletins Interior - Power Seat Switch Knobs
Loose/Missing
Bulletin No.: 05-08-50-017
Date: December 14, 2005
TECHNICAL
Subject: Power Front Seat (RPO AN3) Switch Knobs Loose or Missing (Replace Switch Knobs)
Models: 2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV
2002-2006 Chevrolet Avalanche, Silverado, Suburban, Tahoe 2002-2006 GMC Sierra, Yukon,
Yukon XL
with Individual Front Seat Non-Bucket (RPO AN3) and Driver Front Seat Power Adjuster (AG1)
and/or Passenger Front Seat Power Adjuster (AG2)
Condition
Some customers may comment that the power front seat adjuster switch knobs are loose and fall
off or are missing.
Correction
Replace the front seat adjuster switch knob. These knobs were formerly available only as part of
the power seat adjuster switch. DO NOT replace the switch if the knob only needs to be replaced.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Power Seat Switch: >
05-08-50-017 > Dec > 05 > Interior - Power Seat Switch Knobs Loose/Missing > Page 1133
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch
Power Seat Switch: Diagrams Lumbar/Bolster Switch
Lumbar/Bolster Switch - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch > Page 1136
Lumbar/Bolster Switch - Front Passenger
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch > Page 1137
Power Seat Switch: Diagrams Seat Adjuster Switch
Seat Adjuster Switch - Front Passenger
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch > Page 1138
Seat Adjuster Switch - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch > Page 1139
Seat Adjuster Switch - Driver - Full Feature
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Diagrams > Lumbar/Bolster Switch > Page 1140
Seat Adjuster Switch - Front Passenger - Full Feature
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Service and Repair > Seat Switch Bezel Replacement
Power Seat Switch: Service and Repair Seat Switch Bezel Replacement
Seat Switch Bezel Replacement
Removal Procedure
1. Remove the lumbar knob, if equipped.
2. Remove the screws retaining the power seat switch bezel. 3. Disconnect the electrical
connectors. 4. Remove the lumbar support switch. 5. Remove the power seat adjuster switch
assembly.
Installation Procedure
1. Install the power seat adjuster switch assembly to the seat switch bezel. 2. Install the lumbar
support switch to the seat switch bezel. 3. Connect the electrical connectors.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the screws retaining the power seat switch bezel.
Tighten the screws to 2 N.m (18 lb in).
5. Install the lumbar knob, if equipped.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Service and Repair > Seat Switch Bezel Replacement > Page 1143
Power Seat Switch: Service and Repair Seat Switch Replacement - Power
Seat Switch Replacement - Power
Removal Procedure
1. Remove the lumbar knob, if equipped.
2. Remove the power seat switch bezel from the seat.
3. Remove the power seat switch to bezel screws. 4. Remove the power seat switch.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the power seat switch to bezel screws.
Tighten the screws to 2 N.m (18 lb in).
2. Install the power seat switch bezel to the seat. 3. Install the lumbar knob, if equipped.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Seat Switch >
Component Information > Service and Repair > Seat Switch Bezel Replacement > Page 1144
Power Seat Switch: Service and Repair Lumbar Switch Replacement
Lumbar Switch Replacement
Removal Procedure
1. Remove the power seat switch bezel containing the lumbar switch (1) from the seat. 2. Remove
the lumbar switch screws from the power seat switch bezel. 3. Remove the lumbar switch.
Installation Procedure
1. Install the lumbar switch to the power seat switch bezel.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the lumbar switch screws.
Tighten the screws to 2 N.m (18 lb in).
3. Install the power seat switch bezel (1) to the seat.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Power Trunk / Liftgate
Lock Switch > Component Information > Diagrams
Liftgate/Liftglass Ajar Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations
Seat Heater Switch: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations > Page 1151
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations > Page 1152
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations > Page 1153
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations > Page 1154
Seat Heater Switch: Diagrams
Heated Seat Switch - Front Passenger
Heated Seat Switch - LR
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Locations > Page 1155
Heated Seat Switch - RR
Memory/Heated Seat Switch - Driver
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Service and Repair > Heated Seat Switch Replacement - Front
Seat Heater Switch: Service and Repair Heated Seat Switch Replacement - Front
Heated Seat Switch Replacement - Front
Removal Procedure
1. Remove the front door trim panel. 2. Disconnect the electrical connector.
3. Release the retaining clips for the front seat heater switch in order to remove the switch. 4.
Remove the front seat heater switch.
Installation Procedure
1. Install the front seat heater switch to the front trim panel by pressing the switch into place until
the switch is completely seated. 2. Connect the electrical connector to the front seat heater switch.
3. Install the front trim panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Seat Heater Switch >
Component Information > Service and Repair > Heated Seat Switch Replacement - Front > Page 1158
Seat Heater Switch: Service and Repair Heated Seat Switch Replacement - Rear
Heated Seat Switch Replacement - Rear
Removal Procedure
1. Remove the center console end panel.
2. Disconnect the electrical connector. 3. Remove the seat heater switch retaining screws. 4.
Remove the switch from the vehicle.
Installation Procedure
1. Install the switch to the console panel.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the retaining screw.
Tighten the screws to 1.6 N.m (14 lb in).
3. Connect the electrical connector. 4. Install the center console end panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Sunroof / Moonroof
Switch > Component Information > Diagrams
Sunroof Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Sunroof / Moonroof
Switch > Component Information > Diagrams > Page 1162
Sunroof / Moonroof Switch: Service and Repair
REMOVAL PROCEDURE
1. Remove the roof console assembly. 2. Disconnect the electrical connector. 3. Remove the
switch by un-snapping from roof console assembly.
INSTALLATION PROCEDURE
1. Install the switch to roof console assembly by snapping into place. 2. Connect the electrical
connector. 3. Install the roof console assembly. 4. Synchronize the sunroof motor. Refer to Sunroof
Motor Synchronization.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Trunk / Liftgate Switch
> Component Information > Diagrams
Trunk / Liftgate Switch: Diagrams
Cargo Door Ajar Switch
Cargo Door Key Switch - Security - RH
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Body and Frame > Trunk / Liftgate Switch
> Component Information > Diagrams > Page 1166
Liftgate Key Switch - Security
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Level Sensor/Switch > Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Level Sensor/Switch > Component Information > Diagrams > Page 1171
Brake Fluid Level Sensor/Switch: Service and Repair
Master Cylinder Fluid Level Sensor Replacement
Removal Procedure
1. Disconnect the electrical connector from the fluid level sensor.
2. Remove the fluid level sensor (1). Use a needle nose pliers in order to compress the locking tabs
at the opposite side of the master cylinder.
Installation Procedure
1. Install the fluid level sensor (1) until the locking tabs snap into place. 2. Connect the electrical
connector to the fluid level sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Specifications
Brake Fluid Pressure Sensor/Switch: Specifications
Brake Fluid Pressure Sensor (JL4)
...........................................................................................................................................................
16 Nm (12 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Locations > MPA Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Locations > MPA Switch > Page 1177
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
Brake Fluid Pressure Sensor/Switch: Service and Repair Brake Fluid Pressure Sensor
Replacement
Brake Fluid Pressure Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the alien bolt (2) from the Brake Pressure Modulator Valve (BPMV) mounting bracket
(3) located on the sensor side. 3. Raise the BPMV to access the brake fluid pressure sensor.
4. Disconnect the electrical connector from the brake fluid pressure sensor.
Important: The replacement of the old brake fluid pressure sensor must be performed quickly to
reduce the amount of fluid that is lost during the procedure.
5. Use a wrench to keep the brake fluid pressure sensor collar from turning (1).
Remove the brake fluid pressure sensor (2) from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement >
Page 1180
Notice: Refer to Fastener Notice in Service Precautions.
1. Quickly install the new brake fluid pressure sensor (2) to the BPMV as soon as the old sensor
has been removed.
Use a wrench to keep the brake fluid pressure sensor collar from turning (1). Tighten the brake fluid
pressure sensor to 16 Nm (12 ft. lbs.).
2. Install the alien bolt (2) to the Brake Pressure Modulator Valve (BPMV) mounting bracket (3).
Tighten the alien bolt to 9 Nm (7 ft. lbs.).
3. Connect the electrical connector to the brake fluid pressure sensor. 4. Lower the vehicle. 5.
Check and fill the brake fluid level in the master cylinder.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement >
Page 1181
Brake Fluid Pressure Sensor/Switch: Service and Repair Pressure Accumulator Switch
Replacement
Pressure Accumulator Switch Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the bolts (2) that secure the Brake Pressure Modulator Valve (BPMV) (1) to the
mounting bracket (3).
3. Disconnect the electrical connector from the pressure accumulator switch.
4. Position the BPMV to be able to remove the pressure accumulator switch. 5. Remove the
pressure accumulator switch from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Brake Fluid
Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement >
Page 1182
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the pressure accumulator switch to the BPMV.
Tighten the pressure accumulator switch to 3 Nm (30 inch lbs.).
2. Connect the electrical connector to the pressure accumulator switch.
3. Install the Brake Pressure Modulator Valve (BPMV) (1) and the bolts (2) to the mounting bracket
(3).
Tighten the bolts to 9 Nm (7 ft. lbs.).
4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Parking
Brake Warning Switch > Component Information > Specifications
Parking Brake Warning Switch: Specifications
Park Brake Warning Lamp Switch Bolt
.................................................................................................................................................. 3 Nm
(25 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Parking
Brake Warning Switch > Component Information > Specifications > Page 1186
Parking Brake Warning Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Parking
Brake Warning Switch > Component Information > Specifications > Page 1187
Parking Brake Warning Switch: Service and Repair
Park Brake Warning Lamp Switch Replacement
Removal Procedure
1. Remove the body wiring harness junction block but do not disconnect the harness.
2. Remove the park brake warning lamp switch mounting bolt. 3. Remove the park brake warning
lamp switch.
Installation Procedure
1. Install the park brake warning lamp switch.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the park brake lamp switch mounting bolt.
Tighten the bolt to 3 Nm (25 inch lbs.).
3. Install the body wiring harness junction block.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Traction
Control Switch > Component Information > Locations
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Traction
Control Switch > Component Information > Locations > Page 1191
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak
Traction Control Switch: Service and Repair Stabilitrak
Traction Control Switch Replacement (Stabilitrak)
Removal Procedure
1. Remove Instrument Panel (IP) bezel.
2. Gently lift the retaining tabs (2) and remove the stabilitrak switch (3) from the instrument panel
(IP) assembly (1).
3. Disconnect the harness connector from the stabilitrak switch.
Installation Procedure
1. Connect the harness connector to the stabilitrak switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak > Page 1194
2. Install the stabilitrak switch (3) into the Instrument Panel (IP) assembly (1) 3. Ensure that the
switch is secure into both retaining tabs (2). 4. Install instrument panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak > Page 1195
Traction Control Switch: Service and Repair Traction Control
Traction Control Switch Replacement (Traction Control)
Removal Procedure
1. Remove instrument panel (IP) bezel.
2. Gently lift the switch retaining tabs (1) and remove the traction control switch (2) from the
Instrument Panel (IP) assembly (3). 3. Disconnect the harness connector from the traction control
switch.
Installation Procedure
1. Connect the harness connector to the traction control switch.
2. Install the traction control switch (2) into the instrument panel (IP) assembly (3), making sure that
all of the switch retaining tabs (1) are engaged. 3. Install Instrument Panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1204
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1205
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1206
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1207
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1208
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1209
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1210
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible
Front Wheel Speed Sensor Corrosion > Page 1211
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > NHTSA05V379000 > Aug > 05 > Recall
05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: Recalls Recall 05V379000: Wheel Speed Sensor Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1220
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1221
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1222
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1223
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1224
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1225
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1226
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1227
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel
Speed Sensor Corrosion > Page 1228
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May > 09 >
Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: Customer Interest Brakes - Low Speed ABS Activation/No DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May > 09 >
Brakes - Low Speed ABS Activation/No DTC's Set > Page 1234
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 1240
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1245
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1246
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1247
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1248
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1249
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1250
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1251
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1252
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1261
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1262
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1263
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1264
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1265
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1266
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1267
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1268
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1269
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 1275
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1281
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1282
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1283
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1284
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1285
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1286
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1287
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 1288
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1297
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1298
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1299
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1300
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1301
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1302
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1303
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1304
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 1305
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Page 1306
Wheel Speed Sensor: Specifications
Front Wheel Speed Sensor Mounting Bolt
............................................................................................................................................... 18 Nm
(13 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Technical Service Bulletins > Page 1307
Wheel Speed Sensor - RF (4WD)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Diagrams > LF
Wheel Speed Sensor (WSS) - LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Diagrams > LF > Page 1310
Wheel Speed Sensor (WSS) - RF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Diagrams > Page 1311
Wheel Speed Sensor: Service and Repair
Wheel Speed Sensor Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the brake rotor (2). 4. Remove the Wheel Speed Sensor (WSS) mounting bolt.
Notice: Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a
screwdriver, or other device to pry the sensor out of the bore. Prying will cause the sensor body to
break off in the bore.
5. Remove the wheel speed sensor (5) from the hub/bearing assembly (4). 6. Remove the WSS
cable mounting clip from the knuckle. 7. Remove the WSS cable mounting clip from the upper
control arm. 8. Remove the WSS cable mounting clip from the frame attachment point. 9. Remove
the WSS cable electrical connector.
Installation Procedure
1. Install the WSS (5) into the hub/bearing assembly (4).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the WSS mounting bolt.
Tighten the WSS mounting bolt to 18 Nm (13 ft. lbs.).
3. Install the WSS cable mounting clip to the knuckle. 4. Install the WSS cable mounting clip to the
upper control arm. 5. Install the WSS cable mounting clip to the frame attachment point. 6. Connect
the WSS cable electrical connector. 7. Install the brake rotor (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Wheel
Speed Sensor > Component Information > Diagrams > Page 1312
8. Install the tire and wheel. 9. Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Yaw Rate
Sensor > Component Information > Specifications
Yaw Rate Sensor: Specifications
Yaw Rate Sensor/Lateral Accelerometer Nut
........................................................................................................................................ 10 Nm (89
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Brakes and Traction Control > Yaw Rate
Sensor > Component Information > Specifications > Page 1316
Yaw Rate Sensor: Service and Repair
Yaw Rate Sensor/Lateral Accelerometer Replacement
Removal Procedure
1. Remove the front floor console bezel. 2. Disconnect the yaw rate sensor/lateral accelerometer
electrical connector.
3. Remove the 3 yaw rate sensor/lateral accelerometer nuts. 4. Remove the yaw rate sensor/lateral
accelerometer from the vehicle.
Installation Procedure
Important: Use care not to bend or distort the bracket that supports the yaw rate sensor/lateral
accelerometer.
1. Install the yaw rate sensor/lateral accelerometer to the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the 3 yaw rate sensor/lateral accelerometer nuts to the bracket.
Tighten the nuts to 10 Nm (89 inch lbs.).
3. Connect the yaw rate sensor/lateral accelerometer electrical connector. 4. Install the front floor
bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Cooling System > Engine - Coolant
Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Cooling System > Engine - Coolant
Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations >
Page 1322
Engine Coolant Temperature (ECT) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Cooling System > Engine - Coolant
Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations >
Page 1323
Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Cooling System > Engine - Coolant
Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations >
Page 1324
1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Level Sensor > Component
Information > Specifications
Oil Level Sensor: Specifications
Oil Level Sensor ..................................................................................................................................
................................................ 13 Nm (115 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Level Sensor > Component
Information > Specifications > Page 1329
Oil Level Sensor: Service and Repair
Engine Oil Level Sensor and/or Switch Replacement
Removal Procedure
1. Drain the engine oil. 2. Disconnect the oil level sensor electrical connector (6).
3. Remove the oil level sensor from the oil pan.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the oil level sensor to the oil pan.
- Tighten the oil level sensor to 13 Nm (115 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Level Sensor > Component
Information > Specifications > Page 1330
2. Connect the oil level sensor electrical connector (6). 3. Fill the engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Level Sensor For ECM >
Component Information > Diagrams
Engine Oil Level Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Pressure Sender >
Component Information > Diagrams
Engine Oil Pressure (EOP) Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Pressure Sender >
Component Information > Diagrams > Page 1337
Oil Pressure Sender: Service and Repair
Engine Oil Pressure Sensor and/or Switch Replacement
- Tools Required J 41712 Oil Pressure Sensor Socket
Removal Procedure
1. If necessary, remove the engine sight shield. 2. Disconnect the oil pressure sensor electrical
connector (1).
3. Using J 41712 or equivalent, remove the oil pressure sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Engine > Oil Pressure Sender >
Component Information > Diagrams > Page 1338
1. Apply sealant GM U.S. P/N 12346004, Canada P/N 10953480, or equivalent, to the threads of
the oil pressure sensor.
Notice: Refer to Fastener Notice in Service Precautions.
2. Using J 41712 or equivalent, install the oil pressure sensor.
- Tighten the oil pressure sensor to 20 Nm (15 ft. lbs.).
3. Connect the oil pressure sensor electrical connector (1). 4. If necessary, install the engine sight
shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Air Temperature Sensor - Upper
Air Temperature Sensor - Upper
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Air Temperature Sensor - Upper > Page 1345
Air Temperature Sensor - Lower
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Air Temperature Sensor - Upper > Page 1346
Air Temperature Sensor - Ambient
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Air Temperature Sensor - Upper > Page 1347
Air Temperature Sensor - Lower Auxiliary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Air Temperature Sensor - Upper > Page 1348
Air Temperature Sensor Assembly - Inside (Over Head)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Ambient Temperature Sensor /
Switch HVAC > Component Information > Diagrams > Page 1349
Ambient Temperature Sensor / Switch HVAC: Service and Repair
REMOVAL PROCEDURE
1. Remove the Park/Turn Signal. 2. Disconnect the electrical connector from the ambient air
temperature sensor (3). 3. Remove the ambient air temperature sensor (3).
INSTALLATION PROCEDURE
1. Install the ambient air temperature sensor (3). 2. Connect the electrical connector to the ambient
air temperature sensor (3). 3. Install the Park/Turn Signal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Blower Motor Switch >
Component Information > Diagrams
HVAC Blower Motor Control Switch - C2 (Part Of HVAC Control Assembly)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Blower Motor Switch >
Component Information > Diagrams > Page 1353
Blower Motor Switch: Service and Repair
BLOWER MOTOR SWITCH REPLACEMENT - AUXILIARY
REMOVAL PROCEDURE
1. Separate the front of the console (1) from the headliner. 2. Remove the blower motor switch (2)
by releasing the tabs at the rear of the switch housing. 3. Disconnect the electrical connector (3).
INSTALLATION PROCEDURE
1. Connect the electrical connector (3). 2. Install the blower motor switch (2) to the switch housing.
3. Install the console (1) to the headliner.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Cabin Temperature Sensor /
Switch > Component Information > Service and Repair
Cabin Temperature Sensor / Switch: Service and Repair
INSIDE AIR TEMPERATURE SENSOR REPLACEMENT (OVERHEAD)
REMOVAL PROCEDURE
1. Remove the left windshield garnish molding. 2. Remove the left center pillar assist handle. 3.
Remove the left center pillar garnish molding. 4. Remove the left sunshade. 5. Remove the
retaining screws from the headliner. 6. Gently pull down the headliner. 7. Remove the inside air
temperature sensor from the headliner. 8. Disconnect the electrical connector from the inside air
temperature sensor.
9. Remove the inside air temperature sensor from the headliner.
INSTALLATION PROCEDURE
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1. Install the inside air temperature sensor to the headliner.
2. Connect the electrical connector to the inside air temperature sensor. 3. Install the screws to the
headliner. 4. Install the left sunshade. 5. Install the left center pillar garnish molding. 6. Install the
left center assist handle. 7. Install the left windshield garnish molding.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Discharge Air Temperature
Sensor / Switch, HVAC > Component Information > Locations > Air Temperature Sensor-Upper Auxiliary
Locations View
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Sensor / Switch, HVAC > Component Information > Locations > Air Temperature Sensor-Upper Auxiliary > Page 1362
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Discharge Air Temperature
Sensor / Switch, HVAC > Component Information > Service and Repair > Air Temperature Sensor Replacement - Upper
Discharge Air Temperature Sensor / Switch: Service and Repair Air Temperature Sensor
Replacement - Upper
REMOVAL PROCEDURE
1. Remove the radio. 2. Disconnect the electrical connector from the upper duct air temperature
sensor. 3. Remove the upper duct air temperature sensor from the air duct by prying out of the
duct.
INSTALLATION PROCEDURE
1. Install the upper duct air temperature sensor to the air duct. 2. Connect the electrical connector
to the upper duct air temperature sensor. 3. Install the radio.
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Page 1365
Discharge Air Temperature Sensor / Switch: Service and Repair Air Temperature Sensor
Replacement - Upper Auxiliary
REMOVAL PROCEDURE
1. Remove the right side C-Pillar Trim Panel. 2. Disconnect the electrical connector from the rear
upper A/C temperature sensor (11). 3. Remove the rear upper A/C temperature sensor (11) from
the air distribution duct.
INSTALLATION PROCEDURE
1. Install the rear upper A/C temperature sensor (11) to the air distribution duct. 2. Connect the
electrical connector to the rear upper A/C temperature sensor (11). 3. Install the right side C-Pillar
Trim Panel.
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Page 1366
Discharge Air Temperature Sensor / Switch: Service and Repair Air Temperature Sensor
Replacement - Lower
REMOVAL PROCEDURE
1. Remove the lower duct air temperature sensor (3) and wiring harness assembly from the floor air
outlet (2). 2. Disconnect the electrical connector from the lower duct air temperature sensor (3).
INSTALLATION PROCEDURE
1. Connect the lower duct air temperature sensor (3) to the electrical connector. 2. Install the lower
duct air temperature sensor (3) and wiring harness assembly to the floor air outlet (2).
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Page 1367
Discharge Air Temperature Sensor / Switch: Service and Repair Air Temperature Sensor
Replacement - Lower Auxiliary
REMOVAL PROCEDURE
1. Remove the right side C-Pillar Trim Panel. 2. Disconnect the electrical connector from the
auxiliary lower A/C temperature sensor (10). 3. Remove the auxiliary lower A/C temperature sensor
(10) from the air distribution duct.
INSTALLATION PROCEDURE
1. Install the rear lower A/C temperature sensor (10) to the air distribution duct. 2. Connect the
electrical connector to the rear lower A/C temperature sensor (10). 3. Install the right side C-Pillar
Trim Panel.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Refrigerant Pressure Sensor /
Switch, HVAC > Low Pressure Sensor / Switch, HVAC > Component Information > Technical Service Bulletins > Air
Conditioning - Diagnose A/C Low Pressure Switch
Low Pressure Sensor / Switch: Technical Service Bulletins Air Conditioning - Diagnose A/C Low
Pressure Switch
INFORMATION
Bulletin No.: 04-01-38-010A
Date: January 21, 2010
Subject: Diagnostic Information to Accurately Diagnose A/C Low Pressure Switch Using Kent
Moore Special Tool GE-47742
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2007
Chevrolet Silverado 2000-2006 Chevrolet Suburban, Tahoe 2002-2007 Chevrolet Avalanche
1999-2007 GMC Sierra 2000-2006 GMC Yukon, Yukon XL 2001-2006 GMC Yukon Denali XL
2001-2007 GMC Sierra Denali, Yukon Denali XL 2003-2008 HUMMER H2 with Air Conditioning
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 04-01-38-010 (Section 01 - HVAC).
Currently, technicians cannot accurately determine the air conditioning (A/C) low pressure switch
open/close pressure point by measuring pressure at the low side service port. This is because the
evaporator is between the low side service port and the A/C low pressure switch. Correlating
pressures measured at the low side service port to actual pressures at the A/C low pressure switch
port is difficult because of the multiple variables that impact pressure drop across the evaporator.
Providing a pressure range that would take into account all these variables would result in a
pressure range that would be too broad to be useful for diagnostic purposes. Kent Moore special
tool GE-47742 will allow technicians to monitor the actual pressures at which the A/C low pressure
switch opens and closes under actual operating conditions.
Technicians are to use the following steps to install and use Kent Moore special tool GE-47742 to
measure A/C low pressure switch opening and closing pressures:
1. Disconnect the wire harness from the A/C low pressure switch. 2. Remove the A/C low pressure
switch from the accumulator. 3. Install the A/C low pressure switch, using the threaded port with an
O-ring, onto special tool GE-47742. 4. Install special tool GE-47742, with the A/C low pressure
switch attached, onto the accumulator.
Important Removing the seal from the A/C low pressure switch wire harness connector is required.
Failure to remove the seal before plugging it into the switch will lead to misdiagnosis. The "plunger
effect" of plugging the connector with a seal into the A/C low pressure switch induces a pressure
on the back side of the switch. This pressure will skew the opening/closing characteristics of the
switch 34-69 kPa (5-10 psi) until the pressure bleeds off. The time required for the connection
induced pressure to bleed off can be 20 minutes or longer.
5. Remove the seal from the A/C low pressure switch wire harness connector. 6. Connect the wire
harness, without the seal, to the A/C low pressure switch. 7. Connect the low side service hose
from the ACR2000(R) or GE-48800 to the service port on special tool GE-47742. 8. Connect a
Tech2(R) to the vehicle. 9. Start the vehicle and maintain an engine speed of 1500 RPM. Set the
HVAC controls as follows:
- Set the A/C control switch to ON.
- Set the mode control switch to A/C and engage recirculation mode.
- Set the blower motor speed to LOW.
- Set the temperature control to full cold.
- Set the auxiliary blower motor speed to LOW. If equipped.
- Set the auxiliary temperature control to full cold. If equipped.
- The vehicle must be operating with no sun load (in the shade).
10. Use the Tech2(R) to determine the A/C low pressure switch status and the ACR2000(R) or
GE-48800 to determine the A/C low side pressure.
Simultaneously monitor the switch status and the pressure at which the A/C low pressure switch
opens and closes. The Tech2(R) will display switch status as "Normal" for Closed and "Low
Pressure" for Open. A properly operating switch should open between 138-172 kPa (20-25 psi)
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Conditioning - Diagnose A/C Low Pressure Switch > Page 1373
and close between 275-317 kPa (40-46 psi).
11. Remove special tool GE-47742 after diagnosis is complete. 12. Install a new O-ring on the A/C
low pressure switch port on the accumulator. Lightly coat the new O-ring seal with mineral base
525 viscosity
refrigerant oil.
13. Install the A/C low pressure switch onto the accumulator.
Tighten Tighten the A/C low pressure switch to 6 Nm (44 lb in).
Important Remember to install the seal back onto the A/C low pressure switch wire harness
connector. Failure to replace the seal could result in terminal corrosion.
14. Reconnect the wire harness to the A/C low pressure switch.
Disclaimer
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - HVAC > Solar Sensor, HVAC >
Component Information > Locations
Locations View
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Component Information > Locations > Page 1377
Sunload Sensor
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Solar Sensor: Service and Repair
SUN LOAD SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Remove the instrument panel upper trim pad. 2. Turn the Sun Load Sensor (2)1/4 turn and
remove it from the upper trim pad. 3. Disconnect the electrical connector.
INSTALLATION PROCEDURE
1. Connect the electrical connector. 2. Install the sun load sensor (2) to the upper trim pad turning it
1/4 turn to secure it in place. 3. Install the instrument panel upper trim pad.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions
Dimmer Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 1384
Electrical Symbols Part 1
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Electrical Symbols Part 2
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Component Information > Diagrams > Diagram Information and Instructions > Page 1386
Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 1387
Electrical Symbols Part 4
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Dimmer Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1407
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1408
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1409
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1410
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1411
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1412
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1413
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Dimmer Switch >
Component Information > Diagrams > Diagram Information and Instructions > Page 1414
Dimmer Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo
Door Ajar Switch - Right Cargo
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1419
Mini Wedge (Door Jamb Switch) - LF - C1 - Base
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1420
Mini Wedge (Door Jamb Switch) - LF - C1 - Uplevel/Luxury
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1421
Mini Wedge (Door Jamb Switch) - LF - C3 - Uplevel/Luxury
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1422
Door Switch: Diagrams
Door Ajar Switch - Right Cargo
Mini Wedge (Door Jamb Switch) - LF - C1 - Base
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1423
Mini Wedge (Door Jamb Switch) - LF - C1 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - LF - C3 - Uplevel/Luxury
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1424
Mini Wedge (Door Jamb Switch) - RF - C1 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - RF - C1 - Base
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1425
Mini Wedge (Door Jamb Switch) - RF - C3 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - C1 - LR
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1426
Mini Wedge (Door Jamb Switch) - C1 - RR
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: > 04-08-49-018E > Jan >
05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Fuel Gauge Sender: Customer Interest Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Bulletin No.: 04-08-49-018E
Date: January 05, 2005
TECHNICAL
Subject: Cranks But No Start, Stall, Inaccurate/Incorrect Fuel Gauge Reading, No Fuel, Vehicle is
Out of Fuel and Fuel Gauge Reads Above Empty (Replace Fuel Level Sensor)
Models: 2001-2004 Cadillac Trucks 1999-2004 Chevrolet and GMC Trucks
with Gasoline Engine (VINs Z, X, V, T, U, N, G, 6, 8 - RPOs LU3, LR4, LM7, LQ4, LQ9, L59,
L18,LK5 L52)
Attention:
Parts are currently available for vehicles with Variable Fuel (VIN Z - RPO L59) vehicles. Please
refer to Corporate Bulletin Number 04-06-04-01 2B or newer for Variable Fuel (VIN Z - RPO L59)
vehicles.
Supercede:
This bulletin is being revised to include information on the Chevrolet Colorado and the GMC
Canyon. Please discard Corporate Bulletin Number 04-08-49-018D (Section 08 - Body and
Accessories).
Condition
Some customers may comment on the vehicle stalling and will not restart, vehicle ran out of fuel,
vehicle appears to be out of fuel but the fuel gauge reads above empty. The fuel gauge may read
1/4 tank.
Cause
Contamination on the fuel sending card may cause inaccurate/incorrect fuel gauge readings.
Correction
Follow the service procedure below for diagnosis and repair of this concern.
1. Confirm that the vehicle is actually out of fuel.
^ If the vehicle is not out of fuel but Engine Cranks but Does Not Run, refer to the appropriate
Service Information.
^ If the vehicle is out of fuel and the gauge does not read empty, test the fuel gauge. Refer to the
following information:
- Fuel Gage Inaccurate or Inoperative Single Tank
- Fuel Gage Inaccurate or Inoperative Dual Tanks
- Fuel Gage Inaccurate or Inoperative Colorado and Canyon
2. If testing reveals that the fuel gauge is operating correctly, replace the fuel sensor assembly and
auxiliary tank fuel level sensor if equipped.
3. Replace the fuel level sensor. Refer to the following appropriate service information:
^ Fuel Level Sensor Replacement 4.8L and 5.3L Engines
^ Fuel Level Sensor Replacement 6.0L Engine - Front Tank
^ Fuel Level Sensor Replacement 6.0L Engine - Rear Tank
^ Fuel Level Sensor Replacement 8.1L vehicles with Front Tank
^ Fuel Level Sensor Replacement 8.1 L vehicles with Rear Tank
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: > 04-08-49-018E > Jan >
05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 1435
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: > 04-08-49-018E > Jan >
05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 1436
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Fuel Gauge Sender: All Technical Service Bulletins Fuel System - Cranks But No Start/Inaccurate
Fuel Gauge
Bulletin No.: 04-08-49-018E
Date: January 05, 2005
TECHNICAL
Subject: Cranks But No Start, Stall, Inaccurate/Incorrect Fuel Gauge Reading, No Fuel, Vehicle is
Out of Fuel and Fuel Gauge Reads Above Empty (Replace Fuel Level Sensor)
Models: 2001-2004 Cadillac Trucks 1999-2004 Chevrolet and GMC Trucks
with Gasoline Engine (VINs Z, X, V, T, U, N, G, 6, 8 - RPOs LU3, LR4, LM7, LQ4, LQ9, L59,
L18,LK5 L52)
Attention:
Parts are currently available for vehicles with Variable Fuel (VIN Z - RPO L59) vehicles. Please
refer to Corporate Bulletin Number 04-06-04-01 2B or newer for Variable Fuel (VIN Z - RPO L59)
vehicles.
Supercede:
This bulletin is being revised to include information on the Chevrolet Colorado and the GMC
Canyon. Please discard Corporate Bulletin Number 04-08-49-018D (Section 08 - Body and
Accessories).
Condition
Some customers may comment on the vehicle stalling and will not restart, vehicle ran out of fuel,
vehicle appears to be out of fuel but the fuel gauge reads above empty. The fuel gauge may read
1/4 tank.
Cause
Contamination on the fuel sending card may cause inaccurate/incorrect fuel gauge readings.
Correction
Follow the service procedure below for diagnosis and repair of this concern.
1. Confirm that the vehicle is actually out of fuel.
^ If the vehicle is not out of fuel but Engine Cranks but Does Not Run, refer to the appropriate
Service Information.
^ If the vehicle is out of fuel and the gauge does not read empty, test the fuel gauge. Refer to the
following information:
- Fuel Gage Inaccurate or Inoperative Single Tank
- Fuel Gage Inaccurate or Inoperative Dual Tanks
- Fuel Gage Inaccurate or Inoperative Colorado and Canyon
2. If testing reveals that the fuel gauge is operating correctly, replace the fuel sensor assembly and
auxiliary tank fuel level sensor if equipped.
3. Replace the fuel level sensor. Refer to the following appropriate service information:
^ Fuel Level Sensor Replacement 4.8L and 5.3L Engines
^ Fuel Level Sensor Replacement 6.0L Engine - Front Tank
^ Fuel Level Sensor Replacement 6.0L Engine - Rear Tank
^ Fuel Level Sensor Replacement 8.1L vehicles with Front Tank
^ Fuel Level Sensor Replacement 8.1 L vehicles with Rear Tank
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 1442
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 1443
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1444
Fuel Gauge Sender: Specifications
Fuel Level Specifications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1445
Fuel Level Specifications Part 2
The values in the table are approximate values based on information obtained from properly
operating vehicles. Actual results may vary slightly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1446
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1447
Fuel Gauge Sender: Diagrams
Fuel Pump/Sender - Secondary
Fuel Pump/Sender - Primary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1448
Fuel Gauge Sender: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Fuel Gauge Sender >
Component Information > Technical Service Bulletins > Page 1449
Fuel Gauge Sender: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Parking Brake
Warning Switch > Component Information > Specifications
Parking Brake Warning Switch: Specifications
Park Brake Warning Lamp Switch Bolt
.................................................................................................................................................. 3 Nm
(25 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Parking Brake
Warning Switch > Component Information > Specifications > Page 1453
Parking Brake Warning Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Instrument Panel > Parking Brake
Warning Switch > Component Information > Specifications > Page 1454
Parking Brake Warning Switch: Service and Repair
Park Brake Warning Lamp Switch Replacement
Removal Procedure
1. Remove the body wiring harness junction block but do not disconnect the harness.
2. Remove the park brake warning lamp switch mounting bolt. 3. Remove the park brake warning
lamp switch.
Installation Procedure
1. Install the park brake warning lamp switch.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the park brake lamp switch mounting bolt.
Tighten the bolt to 3 Nm (25 inch lbs.).
3. Install the body wiring harness junction block.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions
Ambient Light Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1460
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1461
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1462
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1463
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1464
Ambient Light Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1465
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1476
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1477
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Ambient Light
Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1478
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1479
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1480
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1481
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1482
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1483
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1484
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1485
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1486
Equivalents - Decimal And Metric Part 1
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1487
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1488
Various symbols are used in order to describe different service operations.
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1489
Conversion - English/Metric
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Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 1490
Ambient Light Sensor
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Sensor > Component Information > Diagrams > Page 1491
Ambient Light Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the instrument panel top cover. 2. Disconnect the electrical connector (1) to the ambient
light sensor on the underside of the IP top cover. 3. Turn the ambient light sensor 1/4 turn and
remove it from the IP top cover.
INSTALLATION PROCEDURE
1. Install the ambient light sensor to the underside of the IP top cover, turning it 1/4 turn to secure it
in place. 2. Connect the electrical connector (1) to the ambient light sensor on the underside of the
IP top cover. 3. Install the instrument panel top cover.
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Switch > Component Information > Diagrams > Diagram Information and Instructions
Backup Lamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1496
Electrical Symbols Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1497
Electrical Symbols Part 2
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1498
Electrical Symbols Part 3
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1499
Electrical Symbols Part 4
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Backup Lamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1501
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1503
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1504
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1505
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1506
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1508
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1509
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1510
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1511
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1512
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1513
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1514
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1515
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1516
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1517
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1518
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1519
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1520
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1521
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1523
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1524
Various symbols are used in order to describe different service operations.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1525
Conversion - English/Metric
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Brake Light Switch >
Component Information > Locations
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Component Information > Diagrams > Diagram Information and Instructions
Brake Light Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Component Information > Diagrams > Diagram Information and Instructions > Page 1533
Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 1534
Electrical Symbols Part 4
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Component Information > Diagrams > Diagram Information and Instructions > Page 1535
Brake Light Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1538
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Stop Lamp Switch
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Brake Light Switch: Service and Repair
Stop Lamp Switch Replacement
Removal Procedure
1. Disconnect the electrical connector from the stop lamp switch (2). 2. Remove the pushrod
retaining clip (4). 3. Remove the stop lamp switch (2).
Installation Procedure
1. Install the stop lamp switch (2). 2. Install the pushrod retaining clip (4). 3. Connect the electrical
connector to the stop lamp switch (2).
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> Component Information > Locations
Locations View
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> Component Information > Diagrams > Diagram Information and Instructions
Cargo Lamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Cargo Lamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1588
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1590
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1591
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1592
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1593
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1596
Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1598
Cargo Lamp Switch: Connector Views
Fog/Cargo Lamp Switch Part 2
Fog/Cargo Lamp Switch Part 1
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> Component Information > Diagrams > Page 1599
Cargo Lamp Switch: Service and Repair
LAMP SWITCH ASSEMBLY REPLACEMENT - FRONT FOG LAMP AND CARGO LAMP
REMOVAL PROCEDURE
1. Remove the instrument cluster bezel. 2. Remove the fog lamp switch and cargo switch from the
housing. 3. Disconnect the electrical connector(s) from the fog lamp switch. 4. Remove the fog
lamp and cargo lamp switch from the housing.
INSTALLATION PROCEDURE
1. Connect the electrical connector(s) to the fog lamp and cargo lamp switch. 2. Install the fog lamp
switch into the housing. 3. Install the IP trim bezel to the instrument panel.
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> Component Information > Diagrams > Diagram Information and Instructions
Combination Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1604
Electrical Symbols Part 1
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1605
Electrical Symbols Part 2
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1606
Electrical Symbols Part 3
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1607
Electrical Symbols Part 4
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Combination Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1612
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1613
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1614
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1615
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1616
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1617
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1618
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1619
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1620
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1622
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1623
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1624
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1625
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Combination Switch
> Component Information > Diagrams > Diagram Information and Instructions > Page 1627
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1628
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1629
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1630
Equivalents - Decimal And Metric Part 1
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1631
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1632
Various symbols are used in order to describe different service operations.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 1633
Conversion - English/Metric
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo
Door Ajar Switch - Right Cargo
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1638
Mini Wedge (Door Jamb Switch) - LF - C1 - Base
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Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1639
Mini Wedge (Door Jamb Switch) - LF - C1 - Uplevel/Luxury
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1640
Mini Wedge (Door Jamb Switch) - LF - C3 - Uplevel/Luxury
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1641
Door Switch: Diagrams
Door Ajar Switch - Right Cargo
Mini Wedge (Door Jamb Switch) - LF - C1 - Base
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1642
Mini Wedge (Door Jamb Switch) - LF - C1 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - LF - C3 - Uplevel/Luxury
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1643
Mini Wedge (Door Jamb Switch) - RF - C1 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - RF - C1 - Base
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1644
Mini Wedge (Door Jamb Switch) - RF - C3 - Uplevel/Luxury
Mini Wedge (Door Jamb Switch) - C1 - LR
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Door Switch >
Component Information > Diagrams > Door Ajar Switch - Right Cargo > Page 1645
Mini Wedge (Door Jamb Switch) - C1 - RR
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Fog/Driving Lamp
Switch > Component Information > Locations
Fog/Driving Lamp Switch: Locations
Locations View
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Switch > Component Information > Locations > Page 1649
Locations View
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Switch > Component Information > Diagrams > Diagram Information and Instructions
Fog/Driving Lamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1652
Electrical Symbols Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1653
Electrical Symbols Part 2
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1654
Electrical Symbols Part 3
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1655
Electrical Symbols Part 4
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Fog/Driving Lamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1657
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1659
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1660
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1661
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1662
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1663
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1664
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1665
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1666
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1667
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1668
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1670
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1672
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1673
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1674
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Fog/Driving Lamp
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1675
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Fog/Driving Lamp
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1676
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1677
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1678
Equivalents - Decimal And Metric Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1679
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1680
Various symbols are used in order to describe different service operations.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1681
Conversion - English/Metric
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1682
Fog/Driving Lamp Switch: Connector Views
Fog/Cargo Lamp Switch Part 2
Fog/Cargo Lamp Switch Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1683
Rear Wiper/Washer And Fog Lamp Switch
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Switch > Component Information > Service and Repair > Lamp Switch ASSY Replacement - Front Fog Lamp and Cargo
Lamp
Fog/Driving Lamp Switch: Service and Repair Lamp Switch ASSY Replacement - Front Fog Lamp
and Cargo Lamp
REMOVAL PROCEDURE
1. Remove the instrument cluster bezel. 2. Remove the fog lamp switch and cargo switch from the
housing. 3. Disconnect the electrical connector(s) from the fog lamp switch. 4. Remove the fog
lamp and cargo lamp switch from the housing.
INSTALLATION PROCEDURE
1. Connect the electrical connector(s) to the fog lamp and cargo lamp switch. 2. Install the fog lamp
switch into the housing. 3. Install the IP trim bezel to the instrument panel.
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Switch > Component Information > Service and Repair > Lamp Switch ASSY Replacement - Front Fog Lamp and Cargo
Lamp > Page 1686
Fog/Driving Lamp Switch: Service and Repair Fog Lamp Switch Replacement - Rear
REMOVAL PROCEDURE
1. Remove the instrument panel bezel. 2. Pull out the accessary switch housing. 3. Disconnect the
electrical connectors. 4. Remove the fog lamp switch from the accessary switch housing.
INSTALLATION PROCEDURE
1. Install the fog lamp switch into accessary switch housing. 2. Connect the electrical connectors. 3.
Install the accessary switch housing. 4. Install the instrument panel bezel.
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Switch > Component Information > Diagrams > Diagram Information and Instructions
Hazard Warning Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1691
Electrical Symbols Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1692
Electrical Symbols Part 2
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1693
Electrical Symbols Part 3
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1694
Electrical Symbols Part 4
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1695
Hazard Warning Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1696
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1697
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1698
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1714
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1715
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1717
Equivalents - Decimal And Metric Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1718
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1720
Conversion - English/Metric
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Lighting and Horns > Headlamp Dimmer
Switch > Component Information > Diagrams > Diagram Information and Instructions
Headlamp Dimmer Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1725
Electrical Symbols Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1726
Electrical Symbols Part 2
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1727
Electrical Symbols Part 3
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1728
Electrical Symbols Part 4
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1729
Headlamp Dimmer Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1730
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1739
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1741
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1746
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1748
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Component Information > Locations
Locations View
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Headlamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 1763
Electrical Symbols Part 4
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Headlamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Component Information > Diagrams > Diagram Information and Instructions > Page 1776
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Component Information > Service and Repair > Headlamp Switch Replacement
Headlamp Switch: Service and Repair Headlamp Switch Replacement
REMOVAL PROCEDURE
1. Remove the instrument cluster bezel. 2. Unsnap the switch from the housing. 3. Disconnect the
electrical connectors.
4. Remove the switch.
INSTALLATION PROCEDURE
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1. Connect the electrical connectors.
2. Install the headlamp switch by snapping the headlamps switch into place. 3. Install the bezel to
the instrument panel.
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Headlamp Switch: Service and Repair Headlamp Leveling Switch Replacement
REMOVAL PROCEDURE
1. Remove the instrument panel bezel. 2. Pull out the accessary switch housing. 3. Disconnect the
electrical connectors. 4. Remove the head lamp leveling switch from the accessary switch housing.
INSTALLATION PROCEDURE
1. Install the head lamp leveling switch into accessary switch housing. 2. Connect the electrical
connectors. 3. Install the accessary switch housing. 4. Install the instrument panel bezel.
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Component Information > Diagrams > Diagram Information and Instructions
Turn Signal Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Turn Signal Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Component Information > Diagrams > Diagram Information and Instructions > Page 1809
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1810
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1811
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1812
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1813
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Component Information > Diagrams > Diagram Information and Instructions > Page 1814
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1815
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1816
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1818
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1819
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1820
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1821
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Component Information > Diagrams > Diagram Information and Instructions > Page 1822
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Component Information > Diagrams > Diagram Information and Instructions > Page 1825
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 1826
Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Switch > Component Information > Diagrams > Diagram Information and Instructions
Underhood Lamp Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1833
Electrical Symbols Part 2
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Electrical Symbols Part 3
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1835
Electrical Symbols Part 4
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Underhood Lamp Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1844
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1845
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1846
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1847
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1848
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1849
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1850
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1851
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1852
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1853
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1854
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1855
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1856
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1857
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1858
Equivalents - Decimal And Metric Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1859
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1860
Various symbols are used in order to describe different service operations.
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 1861
Conversion - English/Metric
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Accelerator Pedal Position Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Accelerator Pedal Position Sensor > Component Information > Locations >
Page 1867
Accelerator Pedal Position (APP) Sensor
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Page 1868
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Locations View
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Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Information and Instructions > Page 1889
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 1890
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Information and Instructions > Page 1891
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 1892
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Information and Instructions > Page 1893
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 1894
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 1896
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 1897
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 1899
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 1904
Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Locations View
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Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Information and Instructions > Page 1926
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Information and Instructions > Page 1927
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 1928
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Information and Instructions > Page 1929
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 1930
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Information and Instructions > Page 1931
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 1932
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 1934
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 1935
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 1937
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 1940
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 1941
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 1942
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 1943
Conversion - English/Metric
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Information and Instructions > Page 1944
Camshaft Position (CMP) Sensor
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1945
Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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1946
Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Information > Locations
Locations View
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Information > Locations > Page 1950
Engine Coolant Temperature (ECT) Sensor
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Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
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1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
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Locations View
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Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Information and Instructions > Page 1968
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Information and Instructions > Page 1969
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Information and Instructions > Page 1970
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Information and Instructions > Page 1971
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 1972
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Information and Instructions > Page 1973
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 1974
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Information and Instructions > Page 1975
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 1976
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Information and Instructions > Page 1977
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 1978
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 1979
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Information and Instructions > Page 1980
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 1981
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Information and Instructions > Page 1982
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 1983
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 1984
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 1985
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 1986
Various symbols are used in order to describe different service operations.
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 1987
Conversion - English/Metric
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 1988
Crankshaft Position (CKP) Sensor
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1989
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
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CKP System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
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CKP System Variation Learn Procedure > Page 1992
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
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CKP System Variation Learn Procedure > Page 1993
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Service and Repair >
CKP System Variation Learn Procedure > Page 1994
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Fuel Level Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Fuel Level Sensor > Component Information > Locations > Page 1998
Fuel Level Sensor: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
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Fuel Level Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
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Locations View
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Switches - Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page
2003
Fuel Tank Pressure (FTP) Sensor
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2004
Fuel Tank Pressure Sensor: Description and Operation
The FTP sensor measures the difference between the pressure or vacuum in the fuel tank and
outside air pressure. The control module provides a 5-volt reference and a ground to the FTP
sensor. The FTP sensor provides a signal voltage back to the control module that can vary
between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low
voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.
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2005
Fuel Tank Pressure Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel tank. 2. Remove the fuel pressure sensor (1).
INSTALLATION PROCEDURE
1. Install the fuel pressure sensor (1). 2. Install the fuel tank.
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Switches - Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations > Page
2009
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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2010
Intake Air Temperature Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2011
2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set > Page 2020
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set > Page 2021
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set > Page 2027
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set > Page 2028
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Page
2029
Locations View
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 2032
Electrical Symbols Part 1
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 2033
Electrical Symbols Part 2
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 2034
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 2035
Electrical Symbols Part 4
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and Instructions > Page 2036
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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and Instructions > Page 2048
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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and Instructions > Page 2049
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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and Instructions > Page 2050
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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and Instructions > Page 2052
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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and Instructions > Page 2053
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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and Instructions > Page 2055
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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and Instructions > Page 2057
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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and Instructions > Page 2059
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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and Instructions > Page 2060
Various symbols are used in order to describe different service operations.
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and Instructions > Page 2061
Conversion - English/Metric
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and Instructions > Page 2062
Knock Sensor (KS)
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Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
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Switches - Computers and Control Systems > Manifold Pressure/Vacuum Sensor > Component Information > Locations
Locations View
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Page 2069
Manifold Absolute Pressure (MAP) Sensor
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Page 2070
Manifold Pressure/Vacuum Sensor: Service and Repair
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield. 2. Disconnect the manifold absolute pressure (MAP) sensor
electrical connector.
3. Remove the MAP sensor (1) from the intake manifold.
INSTALLATION PROCEDURE
IMPORTANT: Lightly coat the MAP sensor seal with clean engine oil before installing the sensor.
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Page 2071
1. Install the MAP sensor (1). Push the MAP sensor down in order to engage the sensor into the
retainer.
2. Connect the MAP sensor electrical connector. 3. Install the engine sight shield.
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Switches - Computers and Control Systems > Oil Level Sensor For ECM > Component Information > Diagrams
Engine Oil Level Switch
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Locations View
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Oxygen Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Oxygen Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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and Instructions > Page 2092
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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and Instructions > Page 2093
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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and Instructions > Page 2094
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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and Instructions > Page 2095
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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and Instructions > Page 2096
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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and Instructions > Page 2097
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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and Instructions > Page 2098
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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and Instructions > Page 2100
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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and Instructions > Page 2101
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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and Instructions > Page 2103
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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and Instructions > Page 2109
Conversion - English/Metric
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Oxygen Sensor: Connector Views
Delphi
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Delphi)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Delphi)
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Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Delphi)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Delphi)
Denso
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Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Denso)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Denso)
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Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 2113
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Denso)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Denso)
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Oxygen Sensor: Description and Operation
HEATED OXYGEN SENSORS
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases. The PCM uses the
signal voltage from the fuel control HO2S in a Closed Loop in order to adjust the fuel injector pulse
width. While in a Closed Loop, the PCM can adjust fuel delivery in order to maintain an air to fuel
ratio which allows the best combination of emission control and driveability.
If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2117
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2118
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2119
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2120
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2121
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2122
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 2123
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Locations
Locations View
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Information and Instructions
Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information and Instructions > Page 2129
Electrical Symbols Part 1
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Information and Instructions > Page 2130
Electrical Symbols Part 2
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Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 2131
Electrical Symbols Part 3
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Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 2132
Electrical Symbols Part 4
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Information and Instructions > Page 2133
Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Information and Instructions > Page 2134
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Information and Instructions > Page 2136
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 2152
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 2154
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 2155
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 2156
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 2157
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 2158
Conversion - English/Metric
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Information and Instructions > Page 2159
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information >
Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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Diagrams > 4L60-E
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information >
Diagrams > 4L60-E > Page 2168
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Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Adjustments > 4L60-E > Page 2171
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Service and Repair > 4L60-E > Page 2175
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Fuel Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations
Locations View
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Switches - Fuel Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations >
Page 2181
Accelerator Pedal Position (APP) Sensor
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Page 2182
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Page 2183
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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Page 2184
1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Switches - Fuel Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Locations
Locations View
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Information and Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information and Instructions > Page 2190
Electrical Symbols Part 1
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Information and Instructions > Page 2191
Electrical Symbols Part 2
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Information and Instructions > Page 2192
Electrical Symbols Part 3
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Information and Instructions > Page 2193
Electrical Symbols Part 4
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Information and Instructions > Page 2194
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Information and Instructions > Page 2205
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 2206
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Information and Instructions > Page 2207
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 2208
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 2210
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 2211
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Information and Instructions > Page 2212
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 2213
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 2218
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 2219
Conversion - English/Metric
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Information and Instructions > Page 2220
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Fuel Composition Sensor - W/L59 Only
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Flexible Fuel Sensor: Description and Operation
FUEL COMPOSITION SENSOR DESCRIPTION
The Fuel Composition Sensor (FCS), or flex fuel sensor (service parts term), measures the
ethanol-gasoline ratio of the fuel being used in a flexible fuel vehicle. Flexible fuel vehicles can be
operated with a blend of ethanol and gasoline, up to 85 percent ethanol. In order to adjust the
ignition timing and the fuel quantity to be injected, the engine management system requires
information about the percentage of ethanol in the fuel.
The FCS uses quick-connect style fuel connections, an incoming fuel connection, and an outgoing
fuel connection. The two connections have different diameters, to prevent incorrect attachment of
the fuel lines. All fuel passes through the fuel composition sensor before continuing on to the fuel
rail. The fuel composition sensor measures two different fuel related parameters, and sends an
electrical signal to the Powertrain Control Module (PCM) to indicate ethanol percentage, and fuel
temperature.
The fuel composition sensor has a three-wire electrical harness connector. The three wires provide
a ground circuit, a power source, and a signal output to the PCM. The power source is vehicle
system voltage, +12 volts), and the ground circuit connects to chassis ground. The signal circuit
carries both the ethanol percentage and fuel temperature within the same signal, on the same wire.
The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel
temp, and change an output signal accordingly. The electrical characteristic of the FCS signal is a
square-wave digital signal. The signal is both variable frequency and variable pulse width. The
frequency of the signal indicates the ethanol percentage, and the pulse width indicates the fuel
temperature. The PCM provides an internal pull-up to five volts on the signal circuit, and the FCS
pulls the 5 volts to ground in pulses. The output frequency is linear to the percentage of ethanol
content in the fuel. The normal range of operating frequency is between 50 and 150 Hertz, with 50
Hertz representing 0 percent ethanol, and 150 Hertz representing 100 percent ethanol. The normal
pulse width range of the digital pulses is between 1 and 5 milliseconds, with 1 millisecond
representing 40°C (-40°F), and 5 milliseconds representing 125°C (257°F).
The microprocessor inside the sensor is capable of a certain amount of self-diagnosis. An output
frequency of 170 Hertz indicates either that the fuel is contaminated or contains methanol (it should
not), or that an internal sensor electrical fault has been detected. Certain substances dissolved in
the fuel can cause the fuel to be contaminated, raising the output frequency to be higher than the
actual ethanol percentage should indicate. Examples of these substances include water, sodium
chloride (salt), and methanol.
It should be noted that it is likely that the FCS will indicate a slightly lower ethanol percentage than
what is advertised at the fueling station. This is not a fault of the sensor. The reason has to do with
government requirements for alcohol-based motor fuels. Government regulations require that
alcohol intended for use as motor fuel be DENATURED. This means that 100 percent pure ethanol
is first denatured with approximately 4% percent gasoline, before being mixed with anything else.
When an ethanol gasoline mixture is advertised as E85, the 85 percent ethanol was denatured
before being blended with gasoline, meaning an advertised E85 fuel contains only about 81
percent ethanol. The FCS measures the actual percentage of ethanol in the fuel.
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Flexible Fuel Sensor: Service and Repair
FUEL COMPOSITION SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Turn OFF the ignition. 2. Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure. 3.
Raise the vehicle. 4. Remove the fuel composition sensor fuel composition sensor (FCS)
attachment nuts (1).
5. Disconnect the FCS inlet and outlet pipes from the FCS.
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6. Disconnect the FCS electrical connector (1). 7. Remove the FCS and bracket assembly from the
frame rail.
8. Remove the FCS bolts and remove from the bracket.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the FCS to the bracket and install bolts.
Tighten Tighten bolts to 10 N.m (89 lb in).
2. Install FCS and bracket assembly to frame.
3. Install FCS bracket to frame nuts.
Tighten Tighten nuts (1) to 17 N.m (13 lb ft).
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4. Connect the FCS inlet and outlet pipes to the FCS.
5. Connect the FCS electrical connector (1). 6. Lower the vehicle. 7. Start the engine and check for
fuel leaks.
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Locations View
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Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 2250
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 2252
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 2264
Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
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Locations View
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Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Instructions > Page 2289
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Instructions > Page 2290
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Instructions > Page 2291
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Instructions > Page 2292
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Instructions > Page 2303
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Camshaft Position (CMP) Sensor
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Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Locations View
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Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Instructions > Page 2327
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Instructions > Page 2328
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Instructions > Page 2329
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Instructions > Page 2330
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 2340
Equivalents - Decimal And Metric Part 1
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 2341
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 2342
Various symbols are used in order to describe different service operations.
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 2343
Conversion - English/Metric
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 2344
Crankshaft Position (CKP) Sensor
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Page 2345
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 2348
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 2349
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 2350
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Ignition Switch > Ignition Switch Lock Cylinder > Component Information > Technical Service
Bulletins > Ignition Lock Cylinder - Revised Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 2364
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 2365
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
2371
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
2372
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
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Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Page 2373
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2376
Electrical Symbols Part 1
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Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2377
Electrical Symbols Part 2
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Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2378
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2379
Electrical Symbols Part 4
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Page 2380
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Page 2381
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Page 2382
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Page 2394
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Page 2395
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Page 2396
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Page 2397
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Page 2398
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Page 2399
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Page 2400
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Page 2401
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Page 2402
Equivalents - Decimal And Metric Part 1
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Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2403
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2404
Various symbols are used in order to describe different service operations.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2405
Conversion - English/Metric
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions >
Page 2406
Knock Sensor (KS)
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Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Page 2407
Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Air Bag Deactivation
Switch > Component Information > Locations > Component Locations
Air Bag Deactivation Switch: Component Locations
Locations View
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Switch > Component Information > Locations > Component Locations > Page 2415
Locations View
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Switch > Component Information > Locations > Component Locations > Page 2416
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Air Bag Deactivation
Switch > Component Information > Locations > Page 2417
Inflatable Restraint IP Module Disable Switch
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Switch > Component Information > Description and Operation > Inflatable Restraint IP module Disable Switch Indicator
Air Bag Deactivation Switch: Description and Operation Inflatable Restraint IP module Disable
Switch Indicator
The Instrument Panel (IP) module disable switch ON/OFF indicator is an LED located in a position
that can been viewed by the occupants in the front seats. The location varies depending on the
vehicle. When the IP module disable switch is in the disable position, the IP module disable switch
indicator illuminates. When the IP module disable switch is in the enable position, the IP module
disable switch indicator is not illuminated. The IP module disable switch indicator will dim to a lower
intensity when the headlamp switch is turned ON.
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Switch > Component Information > Description and Operation > Inflatable Restraint IP module Disable Switch Indicator >
Page 2420
Air Bag Deactivation Switch: Description and Operation Inflatable Restraint IP Module Disable
Switch
The Instrument Panel (IP) module disable switch is a manual 2-position key switch located inside
the vehicle. The IP module disable switch allows the vehicle operator the ability to enable or
disable the IP module (passenger frontal air bag). The vehicle operator must disable the IP module
if a rear-facing child seat is installed in the front passenger seat. The IP module disable switch
interfaces with the Sensing And Diagnostic Module (SDM) to request the enabling or disabling of
the IP module. The occupants are notified of the enabling or disabling of the IP module via the IP
module disable switch ON/OFF indicator located in the IP module disable switch.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Air Bag Deactivation
Switch > Component Information > Description and Operation > Page 2421
Air Bag Deactivation Switch: Service and Repair
INFLATABLE RESTRAINT IP MODULE DISABLE SWITCH REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the instrument panel trim bezel. 3. Remove the IP module
switch from the lower right opening of the switch plate panel. 4. Disconnect the IP module switch
electrical connector.
INSTALLATION PROCEDURE
1. Connect the IP module switch electrical connector. 2. Install the IP module switch into the lower
right opening of the switch plate panel. 3. Install the instrument panel trim bezel. 4. Enable the SIR
system.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Specifications
Fastener Tightening Specifications
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Locations > Inflatable Restraint Front End Discriminating Sensors
Impact Sensor: Locations Inflatable Restraint Front End Discriminating Sensors
Locations View
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Component Information > Locations > Inflatable Restraint Front End Discriminating Sensors > Page 2427
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Locations > Inflatable Restraint Front End Discriminating Sensors > Page 2428
Impact Sensor: Locations Inflatable Restraint Side Impact Sensors
Locations View
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Component Information > Locations > Inflatable Restraint Front End Discriminating Sensors > Page 2429
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Diagrams > Inflatable Restraint Front End Discriminating Sensor - 10/20 Sensor
Inflatable Restraint Front End Discriminating Sensor - 10/20 Series
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Component Information > Diagrams > Inflatable Restraint Front End Discriminating Sensor - 10/20 Sensor > Page 2432
Inflatable Restraint Electronic Frontal Sensor (EFS)
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Component Information > Diagrams > Inflatable Restraint Front End Discriminating Sensor - 10/20 Sensor > Page 2433
Impact Sensor: Diagrams Inflatable Restraint Side Impact Sensor (SIS)
Inflatable Restraint Side Impact Sensor (SIS) - Left
Inflatable Restraint Side Impact Sensor (SIS) - Right
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service Precautions > Technician Safety Information
Impact Sensor: Technician Safety Information
CAUTION: Be careful when you handle a sensor. Do not strike or jolt a sensor. Before applying
power to a sensor:
^ Remove any dirt, grease, etc. from the mounting surface.
^ Position the sensor horizontally on the mounting surface.
^ Point the arrow on the sensor toward the front of the vehicle.
^ Tighten all of the sensor fasteners and sensor bracket fasteners to the specified torque value.
Failure to follow the correct procedure could cause air bag deployment, personal injury, or
unnecessary SIR system repairs.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service Precautions > Technician Safety Information > Page 2436
Impact Sensor: Vehicle Damage Warnings
CAUTION: Be careful when you handle a sensor. Do not strike or jolt a sensor. Before applying
power to a sensor:
^ Remove any dirt, grease, etc. from the mounting surface.
^ Position the sensor horizontally on the mounting surface.
^ Point the arrow on the sensor toward the front of the vehicle.
^ Tighten all of the sensor fasteners and sensor bracket fasteners to the specified torque value.
Failure to follow the correct procedure could cause air bag deployment, personal injury, or
unnecessary SIR system repairs.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Description and Operation > Inflatable Restraint Front End Discriminating Sensor
Impact Sensor: Description and Operation Inflatable Restraint Front End Discriminating Sensor
The front end discriminating sensor is equipped on some vehicles to supplement SIR system
performance. The discriminating sensor is an electro-mechanical sensor and is not part of the
deployment loops, but instead provides an input to the SDM. The SDM uses the input from the
discriminating sensor to assist in determining the severity of a frontal collision further supporting air
bag deployment. If the SDM determines a deployment is warranted, the SDM will cause current to
flow through the deployment loops deploying the frontal air bags.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Description and Operation > Inflatable Restraint Front End Discriminating Sensor > Page 2439
Impact Sensor: Description and Operation Inflatable Restraint Electronic Frontal Sensor (EFS)
The Electronic Frontal Sensor (EFS) is equipped on some vehicles to supplement SIR system
performance. The EFS is an electronic sensor (accelerometer) and is not part of the deployment
loops, but instead provides an input to the SDM. The EFS can assists in determining the severity of
some frontal collisions. The SDM contains a microprocessor that performs calculations using the
measured accelerations. The SDM compares these calculations to a value stored in memory.
When the generated calculations exceed the stored value, the SDM will cause current to flow
through the frontal deployment loops deploying the frontal air bags.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Description and Operation > Inflatable Restraint Front End Discriminating Sensor > Page 2440
Impact Sensor: Description and Operation Inflatable Restraint Side Impact Sensor
The Side Impact Sensor (SIS) contains a sensing device (accelerometer) which monitors vehicle
acceleration and velocity changes to detect side collisions that are severe enough to warrant air
bag deployment. The SIB is not part of the deployment loop, but instead provides an input to the
SDM. The SDM contains a microprocessor that performs calculations using the measured
accelerations. The SDM compares these calculations to a value stored in memory. When the
generated calculations exceed the stored value, the SDM will cause current to flow through the
side deployment loops deploying the side air bags.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service and Repair > Front End Discriminating Sensor Replacement
Impact Sensor: Service and Repair Front End Discriminating Sensor Replacement
REMOVAL PROCEDURE
1. Disable the SIR system. 2. Remove the engine protection shield (if equipped). 3. Remove the
connector position assurance (CPA) from the inflatable restraint front end discriminating sensor
harness connector.
4. Disconnect the inflatable restraint front end discriminating sensor harness connector from the
sensor.
5. Remove the mounting fasteners. 6. Remove the inflatable restraint front end discriminating
sensor from the vehicle.
IMPORTANT: The following procedure should be utilized in the event that the sensor mounting
holes or fasteners are damaged to the extent that the sensor may no longer be properly mounted.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service and Repair > Front End Discriminating Sensor Replacement > Page 2443
7. Perform the following steps in order to complete the fastener repair:
7.1. Remove and discard the improperly installed fastener.
7.2. Chisel off the damaged weld nut.
7.3. Condition the front end lower tie surface where the new weld nut is to be installed.
7.4. Install the new weld nut (GM P/N 11514034) or equivalent into position.
7.5. Migweld the new weld nut to the front end lower tie surface in the correct location.
7.6. Use the new fastener (GM P/N 11515926) or equivalent.
INSTALLATION PROCEDURE
CAUTION: Be careful when you handle a sensor. Do not strike or jolt a sensor. Before applying
power to a sensor: ^
Remove any dirt, grease, etc. from the mounting surface.
^ Position the sensor horizontally on the mounting surface.
^ Point the arrow on the sensor toward the front of the vehicle.
^ Tighten all of the sensor fasteners and sensor bracket fasteners to the specified torque value.
Failure to follow the correct procedure could cause air bag deployment, personal injury, or
unnecessary SIR system repairs.
1. Install the inflatable restraint front end discriminating sensor to the front end lower tie surface.
Make sure the arrow is pointing toward the front of
the vehicle.
NOTE: Refer to Fastener Notice in Service Precautions.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service and Repair > Front End Discriminating Sensor Replacement > Page 2444
2. Install the inflatable restraint front end discriminating sensor mounting fasteners.
Tighten Tighten fasteners to 10 N.m (89 lb in).
3. Connect the inflatable restraint front end discriminating sensor harness connector to the sensor.
4. Install the connector position assurance (CPA) to the inflatable restraint front end discriminating
sensor harness connector. 5. Install the engine protection shield (if equipped). 6. Enable the SIR
system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Impact Sensor >
Component Information > Service and Repair > Front End Discriminating Sensor Replacement > Page 2445
Impact Sensor: Service and Repair Side Impact Sensor Replacement
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the front door trim panel. 3. Loosen the 2 inflatable restraint
side impact sensor fasteners (2). 4. Remove the inflatable restraint side impact sensor (1) from the
door (4). 5. Remove the connector position assurance (CPA) (3) and disconnect the inflatable
restraint side impact sensor yellow 2-way harness connector (5).
INSTALLATION PROCEDURE
1. Connect the inflatable restraint side impact sensor yellow 2-way harness connector (5) to the
inflatable restraint side impact sensor (1). 2. Install the connector position assurance (CPA) (3) to
the inflatable restraint side impact sensor yellow 2-way connector (5). 3. Install the inflatable
restraint side impact sensor (1) to the door (4).
NOTE: Refer to Fastener Notice in Service Precautions.
4. Install the fasteners (2) to the inflatable restraint side impact sensor (1).
Tighten Use only hand tools in order to tighten the fasteners to 10 N.m (89 lb in).
5. Install the door trim panel. 6. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Seat Belt Buckle
Switch > Component Information > Locations
Seat Belt Buckle Switch: Locations
Locations View
In the seat belt buckle
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Seat Belt Buckle
Switch > Component Information > Locations > Page 2449
Seat Belt Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Restraint Systems > Seat Occupant
Sensor > Component Information > Technical Service Bulletins > Restraints - Passenger Presence System Information
Seat Occupant Sensor: Technical Service Bulletins Restraints - Passenger Presence System
Information
INFORMATION
Bulletin No.: 06-08-50-009F
Date: December 23, 2010
Subject: Information on Passenger Presence Sensing System (PPS or PSS) Concerns With
Custom Upholstery, Accessory Seat Heaters or Other Comfort Enhancing Devices
Models:
2011 and Prior GM Passenger Cars and Trucks Equipped with Passenger Presence Sensing
System
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 06-08-50-009E (Section 08 - Body and Accessories).
Concerns About Safety and Alterations to the Front Passenger Seat
Important ON A GM VEHICLE EQUIPPED WITH A PASSENGER SENSING SYSTEM, USE THE
SEAT COVERS AND OTHER SEAT-RELATED EQUIPMENT AS RELEASED BY GM FOR THAT
VEHICLE. DO NOT ALTER THE SEAT COVERS OR SEAT-RELATED EQUIPMENT. ANY
ALTERATIONS TO SEAT COVERS OR GM ACCESSORIES DEFEATS THE INTENDED DESIGN
OF THE SYSTEM. GM WILL NOT BE LIABLE FOR ANY PROBLEMS CAUSED BY USE OF
SUCH IMPROPER SEAT ALTERATIONS, INCLUDING ANY WARRANTY REPAIRS INCURRED.
The front passenger seat in many GM vehicles is equipped with a passenger sensing system that
will turn off the right front passenger's frontal airbag under certain conditions, such as when an
infant or child seat is present. In some vehicles, the passenger sensing system will also turn off the
right front passenger's seat mounted side impact airbag. For the system to function properly,
sensors are used in the seat to detect the presence of a properly-seated occupant. The passenger
sensing system may not operate properly if the original seat trim is replaced (1) by non-GM covers,
upholstery or trim, or (2) by GM covers, upholstery or trim designed for a different vehicle or (3) by
GM covers, upholstery or trim that has been altered by a trim shop, or (4) if any object, such as an
aftermarket seat heater or a comfort enhancing pad or device is installed under the seat fabric or
between the occupant and the seat fabric.
Aftermarket Seat Heaters, Custom Upholstery, and Comfort Enhancing Pads or Devices
Important ON A GM VEHICLE EQUIPPED WITH A PASSENGER SENSING SYSTEM, USE ONLY
SEAT COVERS AND OTHER SEAT-RELATED EQUIPMENT RELEASED AS GM
ACCESSORIES FOR THAT VEHICLE. DO NOT USE ANY OTHER TYPE OF SEAT COVERS OR
SEAT-RELATED EQUIPMENT, OR GM ACCESSORIES RELEASED FOR OTHER VEHICLE
APPLICATIONS. GM WILL NOT BE LIABLE FOR ANY PROBLEMS CAUSED BY USE OF SUCH
IMPROPER SEAT ACCESSORIES, INCLUDING ANY WARRANTY REPAIRS MADE
NECESSARY BY SUCH USE.
Many types of aftermarket accessories are available to customers, upfitting shops, and dealers.
Some of these devices sit on top of, or are Velcro(R) strapped to the seat while others such as seat
heaters are installed under the seat fabric. Additionally, seat covers made of leather or other
materials may have different padding thickness installed that could prevent the Passenger Sensing
System from functioning properly. Never alter the vehicle seats. Never add pads or other devices to
the seat cushion, as this may interfere with the operation of the Passenger Sensing System and
either prevent proper deployment of the passenger airbag or prevent proper suppression of the
passenger air bag.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Starting and Charging > Ignition Switch >
Ignition Switch Lock Cylinder > Component Information > Technical Service Bulletins > Ignition Lock Cylinder - Revised
Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Angle Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD > Page 2467
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Page 2468
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Page 2469
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures
Steering Column Position Sensor: Technical Service Bulletins Steering - Revised Service
Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2474
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2475
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2476
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2477
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2478
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2479
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2480
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Steering Revised Service Procedures > Page 2481
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2482
Steering Column Position Sensor: Service and Repair
This article has been updated with TSB# 03-02-36-002
REVISED STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT PROCEDURE AND STEERING WHEEL POSITION SENSOR CENTERING
PROCEDURE
STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. 2. Remove the steering column from the vehicle.
3. Remove the following from the steering shaft:
A. steering shaft seal (7) B. sensor retainer (6) C. steering wheel position sensor (5), refer to
Steering Wheel Position Sensor Centering. D. two lower spring retainers (4) E. lower bearing
spring (3) F. lower bearing seat (2) G. adapter and bearing assembly (1)
INSTALLATION PROCEDURE
1. Install the following onto the steering shaft:
A. adapter and bearing assembly (1) B. lower bearing seat (2) C. lower bearing spring (3) D. 2
lower spring retainers (4) E. steering wheel position sensor (5) refer to Steering Wheel Position
Sensor Centering. F. sensor retainer (6) G. steering shaft seal (7) H. Enable the SIR system.
2. Install the steering column to the vehicle. 3. Enable the SIR system.
STEERING WHEEL POSITION SENSOR CENTERING
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2483
IMPORTANT: Identify the type of steering wheel position sensor from the illustrations below
BEFORE removing the sensor from the steering column. Once you have identified the steering
wheel position sensor, follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
IMPORTANT: If reusing the existing sensor, you do not have to align the sensor before removal.
Centering is not required when it is time to reinstall.
3. Remove the connector from the sensor. 4. Remove the sensor (1) from the adapter and bearing
assembly. 5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
IMPORTANT: If reusing the existing sensor, you must make an alignment mark on the rotor flange
cuff (3) before removing the sensor. Failure to do so will cause misalignment when installing the
sensor. A new sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3). 8. Remove the connector from the
sensor. 9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2484
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor. 13. Remove the sensor from the adapter and bearing
assembly. 14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor. 17. Remove the sensor clip from the sensor. 18.
Remove the sensor from the adapter and bearing assembly. 19. To install the sensor, proceed to
step 13 in the installation section.
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor. 22. Remove the sensor from the adapter and bearing
assembly. 23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2485
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor. 26. Remove the sensor from the adapter and bearing
assembly. 27. To install the sensor, proceed to step 21 in the installation section.
INSTALLATION PROCEDURE
IMPORTANT: If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of
the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 4. Install the connector to the sensor. 5. From the technicians point
of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 8. Install the connector to the sensor.
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2486
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 20. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
2487
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 24. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Specifications
Ride Height Sensor: Specifications
Front Position Sensor Link Bracket Bolt
................................................................................................................................................. 9 Nm
(80 inch lbs.) Front Position Sensor Mounting Bolt
.................................................................................................................................................. 12 Nm
(106 inch lbs.) Rear Position Sensor Link Bracket Bolt
................................................................................................................................................... 25
Nm (18 ft. lbs.) Rear Position Sensor Mounting Bolt
................................................................................................................................................... 12
Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 2494
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 2495
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 2496
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Service and Repair > Front
Position Sensor Link Assembly Replacement - Electronic Suspension
Ride Height Sensor: Service and Repair Front Position Sensor Link Assembly Replacement Electronic Suspension
Front Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the mounting bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the mounting bracket.
2. Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Service and Repair > Front
Position Sensor Link Assembly Replacement - Electronic Suspension > Page 2499
Ride Height Sensor: Service and Repair Rear Position Sensor Link Assembly Replacement Electronic Suspension
Rear Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the frame bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the frame bracket. 2.
Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Steering Angle Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD > Page 2505
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Page 2506
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Page 2507
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Suspension > Suspension Control Pressure Sensor/Switch > Component Information > Service and Repair
Suspension Control Pressure Sensor/Switch: Service and Repair
"For information regarding this component please refer to air dryer suspension control service and
repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Steering and Suspension > Sensors and
Switches - Wheels and Tires > Tire Pressure Sensor > Component Information > Technical Service Bulletins > Tire Monitor
System - TPM Sensor Information
Tire Pressure Sensor: Technical Service Bulletins Tire Monitor System - TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E > Page 2523
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > Page 2524
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 2529
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 2530
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 2531
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 2532
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 2533
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E > Page
2539
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E > Page
2542
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E >
Page 2545
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E >
Page 2546
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E >
Page 2547
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 2553
Transmission Speed Sensor: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page
2556
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page
2557
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - A/T > Transmission Temperature Sensor/Switch, A/T > Component Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Technical Service Bulletins >
Customer Interest for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service
4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Technical Service Bulletins >
All Technical Service Bulletins for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Transfer Case
Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Transfer Case
Shift Control Switch - C1 > Page 2577
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Page 2578
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Page 2579
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Technical Service Bulletins >
Drivetrain - Updated Transfer Case Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Technical Service Bulletins >
Page 2584
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft Speed
Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft Speed
Sensor - Front > Page 2587
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic) > Page 2590
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic) > Page 2591
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic) > Page 2592
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic) > Page 2593
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Transmission and Drivetrain > Sensors
and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG
149-NP (One Speed Automatic) > Page 2594
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions
Power Window Switch: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2601
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2602
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2603
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2604
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2605
Power Window Switch: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2617
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2618
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2619
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2620
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2621
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2622
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2623
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2624
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2625
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2626
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2627
Equivalents - Decimal And Metric Part 1
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2628
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2629
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2630
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2631
Power Window Switch: Connector Views
Window Switch - LR/RR
Window/Door Lock Switch - Driver (Except Base)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2632
Window/Door Lock Switch - Driver Connector C1 (Except Base)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2633
Window/Door Lock Switch - Driver Connector C2 (Except Base)
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
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Switch > Component Information > Diagrams > Diagram Information and Instructions > Page 2634
Window/Door Lock Switch - Front Passenger
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Windows and Glass > Power Window
Switch > Component Information > Service and Repair > Power Window Switch Replacement
Power Window Switch: Service and Repair Power Window Switch Replacement
REMOVAL PROCEDURE
1. Remove the power accessory switch panel. 2. Disconnect the power window switch electrical
connector. 3. Remove the screws from the window switch. 4. Remove the switch from the switch
panel by lifting the rear of the switch and sliding the switch out from the switch panel.
INSTALLATION PROCEDURE
1. Install the switch to the switch panel sliding the front tabs in first. Rock the switch down in order
to seat the switch completely.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the screws to the window switch.
Tighten Tighten the window switch screws to 2 N.m (18 lb in).
3. Connect the electrical connector to the window switch. 4. Install the power accessory switch
panel.
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Switch > Component Information > Service and Repair > Power Window Switch Replacement > Page 2637
Power Window Switch: Service and Repair Power Window Switch Replacement - Rear Door
REMOVAL PROCEDURE
1. Use a small flat-bladed tool in order to carefully pry the door power window switch from the door
trim panel. 2. Disconnect the electrical connector from the switch.
INSTALLATION PROCEDURE
1. Connect the electrical connector to the switch. 2. Install the switch to the door trim panel by
pressing the switch into place until fully seated.
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Wiper and Washer Systems > Washer
Fluid Level Switch > Component Information > Diagrams
Rear Wiper/Washer Switch
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Wiper and Washer Systems > Windshield
Washer Switch > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Wiper and Washer Systems > Windshield
Washer Switch > Component Information > Locations > Page 2645
Rear Wiper/Washer And Fog Lamp Switch
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Wiper and Washer Systems > Wiper
Switch > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Sensors and Switches > Sensors and Switches - Wiper and Washer Systems > Wiper
Switch > Component Information > Locations > Page 2649
Rear Wiper/Washer And Fog Lamp Switch
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications
Alignment: Technical Service Bulletins Steering/Suspension - Wheel Alignment Specifications
WARRANTY ADMINISTRATION
Bulletin No.: 05-03-07-009C
Date: December 09, 2010
Subject: Wheel Alignment Specifications, Requirements and Recommendations for GM Vehicles
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks
Supercede: This bulletin is being extensively revised to provide technicians and warranty
administrators with an all inclusive guide for wheel alignments. PLEASE FAMILIARIZE YOURSELF
WITH THESE UPDATES BEFORE PERFORMING YOUR NEXT GM WHEEL ALIGNMENT
SERVICE. Please discard Corporate Bulletin Number 05-03-07-009B (Section 03 - Suspension).
Purpose
The purpose of this bulletin is to provide retail, wholesale and fleet personnel with General Motors'
warranty service requirements and recommendations for customer concerns related to wheel
alignment. For your convenience, this bulletin updates and centralizes all of GM's Standard Wheel
Alignment Service Procedures, Policy Guidelines and bulletins on wheel alignment warranty
service.
Important PLEASE FAMILIARIZE YOURSELF WITH THESE UPDATES BEFORE PERFORMING
YOUR NEXT GM WHEEL ALIGNMENT SERVICE.
The following five (5) key steps are a summary of this bulletin and are REQUIRED in completing a
successful wheel alignment service.
1. Verify the vehicle is in an Original Equipment condition for curb weight, tires, wheels, suspension
and steering configurations. Vehicles
modified in any of these areas are not covered for wheel alignment warranty.
2. Review the customer concern relative to "Normal Operation" definitions. 3. Verify that vehicle is
within the "Mileage Policy" range. 4. Document wheel alignment warranty claims appropriately for
labor operations E2000 and E2020.
The following information must be documented or attached to the repair order:
- Customer concern in detail
- What corrected the customer concern?
- If a wheel alignment is performed:
- Consult SI for proper specifications.
- Document the "Before" AND "After" wheel alignment measurements/settings.
- Completed "Wheel Alignment Repair Order Questionnaire" (form attached to this bulletin)
5. Use the proper wheel alignment equipment (preferred with print-out capability), process and the
appropriate calibration maintenance schedules.
Important If it is determined that a wheel alignment is necessary under warranty, use the proper
labor code for the repair. E2000 for Steering Wheel Angle and/or Front Toe set or E2020 for Wheel
Alignment Check/Adjust includes Caster, Camber and Toe set (Wheel alignment labor time for
other component repairs is to be charged to the component that causes a wheel alignment
operation.).
The following flowchart is to help summarize the information detailed in this bulletin and should be
used whenever a wheel alignment is performed.
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 2655
Verify Original Equipment Condition of the Vehicle
- Verify that Original Equipment Tires and Wheels or Official GM Accessory Tires and Wheels are
on the vehicle.
- Verify that aftermarket suspension "Lift" or "Lowering" Kits or other suspension alterations have
NOT been done to the vehicle.
- Check for accidental damage to the vehicle; for example, severe pothole or curb impacts, collision
damage that may have affected the wheel alignment of the vehicle; e.g., engine cradles,
suspension control arms, axles, wheels, wheel covers, tires may show evidence of damage/impact.
- Check to be sure vehicle has seen "Normal Use" rather than abuse; e.g., very aggressive driving
may show up by looking at the tires and condition of the vehicle.
- Check for other additional equipment items that may significantly affect vehicle mass such as
large tool boxes, campers, snow plow packages (without the snowplow RPO), etc., especially in
trucks and cutaway/incomplete vehicles. Significant additional mass can affect trim height and
wheel alignment of the vehicle and may necessitate a customer pay wheel alignment when placed
semi-permanently in the vehicle (Upfitter instructions are to realign the vehicle after placement of
these types of items. (This typically applies to trucks and incomplete vehicles that can be upfit with
equipment such as the above.)
Customer Concerns, "Normal Operation" Conditions and "Mileage Policy"
Possible Concerns
The following are typical conditions that may require wheel alignment warranty service:
1. Lead/Pull: defined as "at a constant highway speed on a typical straight road, the amount of
effort required at the steering wheel to maintain the
vehicle's straight heading."
Important Please evaluate for the condition with hands-on the steering wheel. Follow the "Vehicle
Leads/Pulls" diagnostic tree located in SI to determine the cause of a lead/pull concern. Lead/Pull
concerns can be due to road crown or road slope, tires, wheel alignment or even in rare
circumstances a steering gear issue. Lead/pull concerns due to road crown are considered
"Normal Operation" and are NOT a warrantable condition -- the customer should be advised that
this is "Normal Operation."
Important Some customers may comment on a "Lead/Pull" when they hold the steering wheel in a
level condition. If so, this is more likely a "steering wheel angle" concern because the customer is
"steering" the vehicle to obtain a "level" steering wheel.
2. Steering wheel angle to the left or right (counter-clockwise or clockwise, respectively): Defined
as the steering wheel angle (clocking)
deviation from "level" while maintaining a straight heading on a typical straight road.
3. Irregular or Premature tire wear: Slight to very slight "feathering" or "edge" wear on the
shoulders of tires is NOT considered unusual and
should even out with a tire rotation; if the customer is concerned about a "feathering" condition of
the tires, the customer could be advised to rotate the tires earlier than the next scheduled
mileage/maintenance interval (but no later than the next interval). Be sure to understand the
customer's driving habits as this will also heavily influence the tire wear performance; tire wear from
aggressive or abusive driving habits is NOT a warrantable condition.
Important Slight or mild feathering, cupping, edge or heel/toe wear of tire tread shoulders is
"normal" and can show up very early in a tire/vehicle service mileage; in fact, some new tires can
show evidence of feathering from the factory. These issues do NOT affect the overall performance
and tread life of the tire. Dealer personnel should always check the customer's maintenance
records to ensure that tire inflation pressure is being maintained to placard and that the tires are
being rotated (modified-X pattern) at the proper mileage intervals. Wheel alignments are NOT to be
performed for the types of "Normal" Tire Feathering shown in Figures 1-4 below.
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Figure 1: Full Tread View - "NORMAL" Tire "Feathering" Wear on the Shoulder/Adjacent/Center
Ribs
Figure 2: Tire Shoulder View Example 1 - "NORMAL" Tire "Feathering" Wear on the Shoulder
Figure 3: Tire Shoulder View Example 2 - "NORMAL" Tire "Feathering" Wear
Figure 4: Detail Side View of Tire Shoulder Area - "NORMAL" Tire "Feathering" Wear
Important When a wheel alignment is deemed necessary for tire wear, be sure to document on the
repair order, in as much detail as possible, the severity and type of tire wear (e.g., severe center
wear or severe inside or outside shoulder wear) and the position of the tire on the vehicle (RF, LF,
LR, RR). Please note the customer's concern with the wear such as, noise, appearance, wear life,
etc. A field product report with pictures of the tire wear condition is recommended. Refer to
Corporate Bulletin Number 02-00-89-002J and #07-00-89-036C.
4. Other repairs that affect wheel alignment; e.g., certain component replacement such as
suspension control arm replacement, engine cradle
adjustment/replace, steering gear replacement, steering tie rod replace, suspension strut/shock,
steering knuckle, etc. may require a wheel alignment.
Important If other components or repairs are identified as affecting the wheel alignment, policy calls
for the wheel alignment labor time to be charged to the replaced/repaired component's labor
operation time rather than the wheel alignment labor operations.
Important Vibration type customer concerns are generally NOT due to wheel alignment except in
the rare cases; e.g., extreme diagonal wear across the tread. In general, wheel alignments are
NOT to be performed as an investigation/correction for vibration concerns.
"Normal Operation" Conditions
Vehicle Lead/Pull Due to Road Crown or Slope:
As part of "Normal Operation," vehicles will follow side-to-side or left to right road crown or slope.
Be sure to verify from the customer the types of roads they are driving as they may not recognize
the influence of road crown on vehicle lead/pull and steering wheel angle. If a vehicle requires
significant steering effort to prevent it from "climbing" the road crown there may be an issue to be
looked into further.
Important
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Steering/Suspension - Wheel Alignment Specifications > Page 2657
A wheel alignment will generally NOT correct vehicles that follow the road crown since this is within
"Normal Operation."
Mileage Policy
The following mileage policy applies for E2020 and E2000 labor operations: Note
Wheel Alignment is NOT covered under the New Vehicle Limited Warranty for Express and Savana
Cutaway vehicles as these vehicles require Upfitters to set the wheel alignment after completing
the vehicles.
- 0-800 km (0-500 mi): E2000/E2020 claims ONLY allowed with Call Center Authorization. Due to
the tie down during shipping, the vehicle's suspension requires some time to reach normal
operating position. For this reason, new vehicles are generally NOT to be aligned until they have
accumulated at least 800 km (500 mi). A field product report should accompany any claim within
this mileage range.
- 801-12,000 km (501-7,500 mi):
- If a vehicle came from the factory with incorrect alignment settings, any resulting off-angle
steering wheel, lead/pull characteristics or the rare occurrence of excessive tire wear would be
apparent early in the life of the vehicle. The following policy applies:
- Vehicles 100% Factory Set/Measured for Caster/Camber/Toe - Escalade/ESV/EXT,
Tahoe/Suburban, Yukon/XL/Denali, Silverado/Sierra, Express/Savana, Corvette and
Colorado/Canyon: E2000/E2020 Claims: Call Center Authorization Required
- All Vehicles NOT 100% Factory Set/Measured for Caster/Camber/Toe as noted above:
E2000/E2020 Claims: Dealer Service Manager Authorization Required
- 12,001 km and beyond (7,501 miles and beyond): During this period, customers are responsible
for the wheel alignment expense or dealers may provide on a case-by case basis a one-time
customer enthusiasm claim up to 16,000 km (10,000 mi). In the event that a defective component
required the use of the subject labor operations, the identified defective component labor operation
will include the appropriate labor time for a wheel alignment as an add condition to the component
repair.
Important Only one wheel alignment labor operation claim (E2000 or E2020) may be used per VIN.
Warranty Documentation Requirements
When a wheel alignment service has been deemed necessary, the following items will need to be
clearly documented on/with the repair order:
- Customer concern in detail
- What corrected the customer concern?
- If a wheel alignment is performed:
- Consult SI for proper specifications.
- Document the "Before" AND "After" wheel alignment measurements/settings.
- Completed "Wheel Alignment Repair Order Questionnaire" (form attached to this bulletin)
1. Document the customer concern in as much detail as possible on the repair order and in the
warranty administration system. Preferred examples:
- Steering wheel is off angle in the counterclockwise direction by approximately x degrees or
clocking position.
- Vehicle lead/pulls to the right at approximately x-y mph. Vehicle will climb the road crown. Severe,
Moderate or Slight.
- RF and LF tires are wearing on the outside shoulders with severe feathering.
Important In the event of a lead/pull or steering wheel angle concern, please note the direction of
lead/pull (left or right) or direction of steering wheel angle (clockwise or counterclockwise) on the
repair order and within the warranty claim verbatim.
Important In the event of a tire wear concern, please note the position on the vehicle and where the
wear is occurring on the tire; i.e., the RF tire is wearing on the inside shoulder.
2. Document the technician's findings on cause and correction of the issue. Examples:
- Reset LF toe from 0.45 degrees to 0.10 degrees and RF toe from -0.25 degrees to 0.10 degrees
to correct the steering wheel angle from 5 degrees counterclockwise to 0 degrees.
- Reset LF camber from 0.25 degrees to -0.05 degrees to correct the cross-camber condition of
+0.30 degrees to 0.00 degrees on the vehicle.
- Front Sum toe was found to be 0.50 degrees, reset to 0.20 degrees.
3. Print-out the "Before" and "After" wheel alignment measurements/settings and attach them to the
Repair Order or if print-out capability is not
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available, measurements may also be clearly and legibly handwritten into the Wheel Alignment
Repair Order Questionnaire attached to this bulletin.
4. Attach the Wheel Alignment Repair Order Questionnaire below along with the print-out of
"Before" and "After" wheel alignment measurements to
the Repair Order and retain for use by GM.
Wheel Alignment Equipment and Process
Wheel alignments must be performed with a quality machine that will give accurate results when
performing checks. "External Reference" (image-based camera technology) is preferred. Please
refer to Corporate Bulletin Number 05-00-89-029B: General Motors Dealership Critical Equipment
Requirements and Recommendations.
Requirements:
- Computerized four wheel alignment system.
- Computer capable of printing before and after alignment reports.
- Computer capable of time and date stamp printout.
- Racking system must have jacking capability
- Racking system must be capable of level to 1.6 mm (1/16 in)
- Appropriate wheel stops and safety certification
- Built-in turn plates and slip plates
- Wheel clamps capable of attaching to 20" or larger wheels
- Racking capable of accepting any GM passenger car or light duty truck
- Operator properly trained and ASE-certified (U.S. only) in wheel alignment
Recommendations:
Racking should have front and rear jacking capability.
Equipment Maintenance and Calibration:
Alignment machines must be regularly calibrated in order to give correct information. Most
manufacturers recommend the following:
- Alignment machines with "internal reference" sensors should be checked (and calibrated, if
necessary) every six months.
- Alignment machines with "external reference" (image-based camera technology) should be
checked (and calibrated, if necessary) once a year.
- Racks must be kept level to within 1.6 mm (1/16 in).
- If any instrument that is part of the alignment machine is dropped or damaged in some way,
check the calibration immediately.
Check with the manufacturer of your specific equipment for their recommended service/calibration
schedule.
Wheel Alignment Process
When performing wheel alignment measurement and/or adjustment, the following steps should be
taken:
Preliminary Steps:
1. Verify that the vehicle has a full tank of fuel (compensate as necessary). 2. Inspect the wheels
and the tires for damage. 3. Inspect the tires for the proper inflation and irregular tire wear. 4.
Inspect the wheel bearings for excessive play. 5. Inspect all suspension and steering parts for
looseness, wear, or damage. 6. Inspect the steering wheel for excessive drag or poor return due to
stiff or rusted linkage or suspension components. 7. Inspect the vehicle trim height. 8. Compensate
for frame angle on targeted vehicles (refer to Wheel Alignment Specifications in SI).
Satisfactory vehicle operation may occur over a wide range of alignment angles. However, if the
wheel alignment angles are not within the range of specifications, adjust the wheel alignment to the
specifications. Refer to Wheel Alignment Specifications in SI. Give consideration to excess loads,
such as tool boxes, sample cases, etc. Follow the wheel alignment equipment manufacturer's
instructions.
Measure/Adjust:
Important Prior to making any adjustments to wheel alignment on a vehicle, technicians must verify
that the wheel alignment specifications loaded into their wheel alignment machine are up-to-date
by comparing these to the wheel alignment specifications for the appropriate model and model year
in SI. Using incorrect and/or outdated specifications may result in unnecessary adjustments,
irregular and/or premature tire wear and repeat customer concerns
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Important When performing adjustments to vehicles requiring a 4-wheel alignment, set the rear
wheel alignment angles first in order to obtain proper front wheel alignment angles.
Perform the following steps in order to measure the front and rear alignment angles:
1. Install the alignment equipment according to the manufacturer's instructions. 2. Jounce the front
and the rear bumpers 3 times prior to checking the wheel alignment. 3. Measure the alignment
angles and record the readings.
If necessary, adjust the wheel alignment to vehicle specification and record the before and after
measurements. Refer to Wheel Alignment Specifications in SI.
Important Technicians must refer to SI for the correct wheel alignment specifications. SI is the only
source of GM wheel alignment specifications that is kept up-to-date throughout the year.
Test drive vehicle to ensure proper repair.
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Frame Angle Measurement (Express / Savana Only) ........
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What corrected the customer concern and was the repair verified?
Please Explain: .............
Disclaimer
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Alignment: Technical Service Bulletins Steering/Suspension - Revised Caster/Camber Adjustment
Info - Revised Front Caster and Camber Adjustment Procedure # 02-03-07-002A - (Mar 24, 2005)
Models: 1999-2000 Cadillac Escalade 2002-2005 Cadillac Escalade, Escalade EXT 1999-2005
Chevrolet Express, Silverado, Suburban, Tahoe 2002-2005 Chevrolet Avalanche 1999 GMC
Suburban 1999-2005 GMC Savana, Sierra, Yukon, Yukon XL, Yukon XL Denali
This bulletin is being revised to add model years and clarify the information. Please discard
Corporate Bulletin Number 02-03-07-002 (Section 03 - Suspension).
When performing a wheel alignment on any of the above vehicles, please refer to the Front Caster
and Camber Adjustment Procedure in SI before contacting the GM Technical Assistance Center
(TAC) with issues concerning adjustments, caster out-of-spec, etc.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Specifications > Ride/Trim Height
Inspection Procedure
Alignment: Specifications Ride/Trim Height Inspection Procedure
Trim Height Inspection Procedure
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights
can cause bottoming out over bumps, damage to the suspension components and symptoms
similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns
and before checking the wheel alignment. Perform the following before measuring the trim heights:
1. Set the tire pressures to the pressure shown on the certification label. 2. Check the fuel level.
Add additional weight if necessary to simulate a full tank. 3. Make sure the rear compartment is
empty except for the spare tire. 4. Make sure the vehicle is on a level surface, such as an
alignment rack. 5. Close the doors. 6. Close the hood. 7. All dimensions are measured vertical to
the ground. Trim heights should be within 13 mm (0.5 inch) to be considered correct.
Z Height Measurement
Important: K models only the Z height must be adjusted before the alignment.
The Z height dimension measurement determines the proper ride height for the front end of the
vehicle. Vehicles equipped with torsion bars use an adjusting arm in order to adjust the Z height
dimension. Vehicles without torsion bars have no adjustment and could require replacement of
suspension components. 1. Lift the front bumper of the vehicle up about 38 mm (1.5 inch). 2.
Gently remove your hands. 3. Allow the vehicle to settle into position. 4. Repeat this jouncing
operation 2 more times for a total of 3 times.
5. Measure from the pivot bolt center line (3) down to the lower corner (5) of the lower ball joint (1)
in order to obtain the Z height measurement (4). 6. Push the front bumper of the vehicle down
about 38 mm (1.5 inch). 7. Gently remove your hands. 8. Allow the vehicle to rise. 9. Repeat the
operation for a total of 3 times.
10. Measure the Z dimension. 11. The true Z height dimension number is the average of the high
and the low measurements.
Z Height Adjustment
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Specifications > Ride/Trim Height
Inspection Procedure > Page 2665
1. For vehicles equipped with a torsion bar suspension turn the bolt (1) that contacts the torsion
arm clockwise to raise the and counterclockwise to
lower the height adjustment. One revolution of the bolt (1) into the nut increases the Z height by
approximately 6.0 mm (0.2 inch).
2. For vehicles without torsion bars, replace damaged or worn components as necessary.
D Height Measurement
The D height dimension measurement determines the proper rear end ride height. There is no
adjustment procedure. Repair may require replacement of suspension components. 1. With the
vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 inch). 2. Gently remove your
hands. Allow the vehicle to settle into position. 3. Repeat the jouncing operation 2 more times for a
total of 3 times.
4. Measure the D height by measuring the distance between the bumper bracket and the top of the
rear axle tube. 5. Push the rear bumper downward to 38 mm (1.5 inch). 6. Gently remove your
hands. Allow the vehicle to settle into position. 7. Repeat the jouncing operation 2 more times for a
total of 3 times. 8. Measure the D height dimension. 9. The true D height dimension number is the
average of the high and the low measurements.
10. If these measurements are out of specifications, inspect for the following conditions:
^ Sagging front suspension
^ Sagging rear leaf/coil springs
^ Worn rear suspension components, such as leaf spring bushings
^ Improper tire inflation
^ Improper weight distribution
^ Collision damage
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Alignment: Specifications Wheel Alignment Specifications
Alignment
Wheel Alignment Specifications
Fastener Tightening Specifications
Trim Height Specifications
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Specifications > Page 2668
Alignment: Description and Operation
Caster Description
Caster is the tilting of the uppermost point of the steering axis either forward or backward, when
viewed from the side of the vehicle. A backward tilt is positive (+) and a forward tilt is negative (-).
Caster influences directional control of the steering but does not affect the tire wear and is not
adjustable on this vehicle. Caster is affected by the vehicle height, therefore it is important to keep
the body at its designed height. Overloading the vehicle or a weak or sagging rear spring will affect
caster. When the rear of the vehicle is lower than its designated trim height, the front suspension
moves to a more positive caster. If the rear of the vehicle is higher than its designated trim height,
the front suspension moves to a less positive caster. With too little positive caster, steering may be
touchy at high speed and wheel returnability may be diminished when coming out of a turn. If one
wheel has more positive caster than the other, that wheel will pull toward the center of the vehicle.
This condition will cause the vehicle to pull or lead to the side with the least amount of positive
caster.
Camber Description
Camber is the tilting of the wheels from the vertical when viewed from the front of the vehicle.
When the wheels tilt outward at the top, the camber is positive (+). When the wheel tilts inward at
the top, the camber is negative (-). The amount of tilt is measured in degrees from the vertical.
Camber settings influence the directional control and the tire wear. Too much positive camber will
result in premature wear on the outside of the tire and cause excessive wear on the suspension
parts. Too much negative camber will result in premature wear on the inside of the tire and cause
excessive wear on the suspension parts. Unequal side-to-side camber of 1 degree or more will
cause the vehicle to pull or lead to the side with the most positive camber.
Toe Description
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Toe is a measurement of how much the front and/or rear wheels are turned in or out from a
straight-ahead position. When the wheels are turned in, toe is positive (+). When the wheels are
turned out, toe is negative (-). The actual amount of toe is normally only a fraction of a degree. The
purpose of toe is to ensure that the wheels roll parallel. Toe also offsets the small deflections of the
wheel support system that occur when the vehicle is rolling forward. In other words, with the vehicle
standing still and the wheels set with toe-in, the wheels tend to roll parallel on the road when the
vehicle is moving. Improper toe adjustment will cause premature tire wear and cause steering
instability.
Setback Description
Setback applies to both the front and the rear wheels. Setback is the amount that one wheel may
be aligned behind the other wheel. Setback may be the result of a road hazard or a collision. The
first clue is a caster difference from side-to-side of more than 1 degree.
Thrust Angles Description
The front wheels aim or steer the vehicle. The rear wheels control tracking. This tracking action
relates to the thrust angle (3). The thrust angle is the path that the rear wheels take. Ideally, the
thrust angle is geometrically aligned with the body centerline (2). In the illustration, toe-in is shown
on the left rear wheel, moving the thrust line (1) off center. The resulting deviation from the
centerline is the thrust angle.
Lead/Pull Description
Lead/pull is the deviation of the vehicle from a straight path, on a level road, without hand pressure
on the steering wheel. Lead/pull is usually caused by the following factors: ^
Tire construction
^ Uneven brake adjustment
^ Wheel alignment
The way in which a tire is built may produce lead/pull. The rear tires will not cause lead.
Memory Steer Description
Memory steer is when the vehicle wants to lead or pull in the direction the driver previously turned
the vehicle. Additionally, after turning in the opposite direction, the vehicle will want to lead or pull in
that direction.
Wander Description
Wander is the undesired drifting or deviation of a vehicle to either side from a straight path with
hand pressure on the steering wheel. Wander is a symptom of the vehicle's sensitivity to external
disturbances, such as road crown and crosswind, and accentuated by poor on-center steering feel.
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Specifications > Page 2670
Scrub Radius Description
Ideally, the scrub radius is as small as possible. Normally, the SAI angle and the centerline of the
tire and the wheel intersect below the road surface, causing a positive scrub radius. With struts, the
SAI angle is much larger than the long arm/short arm type of suspension. This allows the SAI angle
to intersect the camber angle above the road surface, forming a negative scrub radius. The smaller
the scrub radius, the better the directional stability. Installing aftermarket wheels that have
additional offset will dramatically increase the scrub radius. The newly installed wheels may cause
the centerline of the tires to move further away from the spindle. This will increase the scrub radius.
A large amount of scrub radius can cause severe shimmy after hitting a bump. Four-wheel drive
vehicles with large tires use a steering damper to compensate for an increased scrub radius. Scrub
radius is not directly measurable by the conventional methods. Scrub radius is projected
geometrically by engineers during the design phase of the suspension.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection
Alignment: Service and Repair Trim Height Inspection
Trim Height Inspection Procedure
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights
can cause bottoming out over bumps, damage to the suspension components and symptoms
similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns
and before checking the wheel alignment. Perform the following before measuring the trim heights:
1. Set the tire pressures to the pressure shown on the certification label. 2. Check the fuel level.
Add additional weight if necessary to simulate a full tank. 3. Make sure the rear compartment is
empty except for the spare tire. 4. Make sure the vehicle is on a level surface, such as an
alignment rack. 5. Close the doors. 6. Close the hood. 7. All dimensions are measured vertical to
the ground. Trim heights should be within 13 mm (0.5 inch) to be considered correct.
Z Height Measurement
Important: K models only the Z height must be adjusted before the alignment.
The Z height dimension measurement determines the proper ride height for the front end of the
vehicle. Vehicles equipped with torsion bars use an adjusting arm in order to adjust the Z height
dimension. Vehicles without torsion bars have no adjustment and could require replacement of
suspension components. 1. Lift the front bumper of the vehicle up about 38 mm (1.5 inch). 2.
Gently remove your hands. 3. Allow the vehicle to settle into position. 4. Repeat this jouncing
operation 2 more times for a total of 3 times.
5. Measure from the pivot bolt center line (3) down to the lower corner (5) of the lower ball joint (1)
in order to obtain the Z height measurement (4). 6. Push the front bumper of the vehicle down
about 38 mm (1.5 inch). 7. Gently remove your hands. 8. Allow the vehicle to rise. 9. Repeat the
operation for a total of 3 times.
10. Measure the Z dimension. 11. The true Z height dimension number is the average of the high
and the low measurements.
Z Height Adjustment
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Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection > Page 2673
1. For vehicles equipped with a torsion bar suspension turn the bolt (1) that contacts the torsion
arm clockwise to raise the and counterclockwise to
lower the height adjustment. One revolution of the bolt (1) into the nut increases the Z height by
approximately 6.0 mm (0.2 inch).
2. For vehicles without torsion bars, replace damaged or worn components as necessary.
D Height Measurement
The D height dimension measurement determines the proper rear end ride height. There is no
adjustment procedure. Repair may require replacement of suspension components. 1. With the
vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 inch). 2. Gently remove your
hands. Allow the vehicle to settle into position. 3. Repeat the jouncing operation 2 more times for a
total of 3 times.
4. Measure the D height by measuring the distance between the bumper bracket and the top of the
rear axle tube. 5. Push the rear bumper downward to 38 mm (1.5 inch). 6. Gently remove your
hands. Allow the vehicle to settle into position. 7. Repeat the jouncing operation 2 more times for a
total of 3 times. 8. Measure the D height dimension. 9. The true D height dimension number is the
average of the high and the low measurements.
10. If these measurements are out of specifications, inspect for the following conditions:
^ Sagging front suspension
^ Sagging rear leaf/coil springs
^ Worn rear suspension components, such as leaf spring bushings
^ Improper tire inflation
^ Improper weight distribution
^ Collision damage
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection > Page 2674
Alignment: Service and Repair Measuring Wheel Alignment
Measuring Wheel Alignment
Steering and vibration complaints are not always the result of improper alignment. One possible
cause is wheel and tire imbalance. Another possibility is tire lead due to worn or improperly
manufactured tires. Lead is the vehicle deviation from a straight path on a level road without
pressure on the steering wheel. Refer to Radial Tire Lead/Pull Correction in order to determine if
the vehicle has a tire lead problem. Before performing any adjustment affecting wheel alignment,
perform the following inspections and adjustments in order to ensure correct alignment readings: ^
Inspect the tires for the proper inflation and irregular tire wear. Refer to Tire Inflation Pressure
Specifications and Tire Diagnosis - Irregular or Premature Wear.
^ Inspect the runout of the wheels and the tires.
^ Inspect the wheel bearings for backlash and excessive play.
^ Inspect the ball joints and tie rod ends for looseness or wear. Inspect the control arms and
stabilizer shaft for looseness or wear.
^ Inspect the steering gear for looseness at the frame.
^ Inspect the struts/shock absorbers for wear, leaks, and any noticeable noises.
^ Inspect the vehicle trim height.
^ Inspect the steering wheel for excessive drag or poor return due to stiff or rusted linkage or
suspension components.
^ Inspect the fuel level. The fuel tank should be full or the vehicle should have a compensating load
added.
Give consideration to excess loads, such as tool boxes, sample cases, etc. If normally carried in
the vehicle, these items should remain in the vehicle during alignment adjustments. Give
consideration also to the condition of the equipment being used for the alignment. Follow the
equipment manufacturer's instructions. Satisfactory vehicle operation may occur over a wide range
of alignment settings. However, if the setting exceeds the service allowable specifications, correct
the alignment to the service preferred specifications. Perform the following steps in order to
measure the front and rear alignment angles: 1. Install the alignment equipment according to the
manufacturer's instructions. 2. Jounce the front and the rear bumpers 3 times prior to checking the
wheel alignment. 3. Measure the alignment angles and record the readings.
Important: When performing adjustments to vehicles requiring a 4-wheel alignment, set the rear
wheel alignment angles first in order to obtain proper front alignment angles.
4. Adjust alignment angles to vehicle specification, if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection > Page 2675
Alignment: Service and Repair Front Wheel Alignment
Front Caster and Camber Adjustment
Front Caster and Camber Adjustment
1. Determine if the vehicle is relative to frame or relative to ground. If caster is relative to frame, the
caster values must be compensated for the
measured frame angle. To determine the frame angle use a digital protractor or equivalent.
2. Frame angle is positive when higher in the rear. Measure both sides of the frame and take an
average from those measurements. Then add the
average frame angle to the caster reading obtained in step 5 of this procedure when making
adjustments.
3. Frame angle is negative when lower in the rear. Measure both sides of the frame and take an
average from the measurements. Then subtract the
average frame angle from the caster reading obtained in step 5 of this procedure when making
adjustments.
4. The caster and camber adjustments are made by rotating the offset cam bolt and the cam in the
slotted frame bracket in order to reposition the
control arm.
Important: Before adjusting the caster and camber angles, jounce the front bumper three times to
allow the vehicle to return to normal height. Measure and adjust the caster and the camber with the
vehicle at curb height. The front suspension Z dimension is indicated in Trim Heights.
5. For an accurate reading, do not push or pull on the tires during the alignment process.
6. Determine the caster angle (2). Be sure to compensate for frame angle where required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection > Page 2676
7. Determine the positive camber (2) or negative camber (3) angle.
8. Remove the pinned adjusting cam insert. Do not reinstall the cam insert. 9. Loosen the upper
control arm cam adjustment bolts.
Notice: Refer to Fastener Notice in Service Precautions.
10. Adjust the caster and the camber angle by turning the cam bolts until the specifications have
been met.
When the adjustments are complete, hold the cam bolt head in order to ensure the cam bolt
position does not change while tightening the nut. Tighten the cam nuts to 190 Nm (140 ft. lbs.).
11. Verify that the caster and the camber are still within specifications. When the caster and
camber are within specifications, adjust the toe.
Front Wheel Toe Adjustment
Front Toe Adjustment
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Alignment > System Information > Service and Repair > Trim Height
Inspection > Page 2677
1. Loosen the jam nut on the tie rod (2). 2. Rotate the inner tie rod (1) to the required toe
specification setting.
Notice: Refer to Fastener Notice in Service Precautions.
3. Tighten the jam nut on the tie rod.
Tighten the tie rod jam to 68 Nm (50 ft. lbs.).
4. Check the toe seeing after tightening. 5. Re-adjust the toe setting if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > Specifications
Fuel Pressure: Specifications
Measure with the Key On Engine Off with the fuel pump commanded ON.
Vin (V,T,U)
Fuel Pressure (gasoline) .....................................................................................................................
................................................................. 55-62 psi
Vin (Z)
Fuel Pressure (ethanol) .......................................................................................................................
................................................................. 48-54 psi
These specifications are taken from the Fuel System Diagnosis. For complete testing of fuel
pressures and volume see Fuel System Diagnosis, See: Powertrain Management/Computers and
Control Systems/Testing and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal
Fuel Pressure: Testing and Inspection Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 2684
Fuel Pressure: Testing and Inspection Fuel System Diagnosis
SYSTEM DESCRIPTION
When you turn ON the ignition switch, the control module enables the fuel pump relay which
powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running
and the control module receives ignition reference pulses. If there are no ignition reference pulses,
the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the
ON position or if the engine stops.
The fuel tank stores the fuel supply. The electric fuel pump supplies fuel through an in-line fuel filter
to the fuel injection system. The pump provides fuel at a higher rate of flow than is needed by the
fuel injection system. The fuel pressure regulator maintains the correct fuel pressure to the fuel
injection system. A separate pipe returns unused fuel to the fuel tank.
TEST DESCRIPTION
Steps 1-2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 2685
Steps 3-7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 2686
Steps 8-13
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 2687
Steps 14-18
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 2688
Steps 19-25
The numbers below refer to the step numbers on the diagnostic table. 2. This step verifies that the
fuel pump is operating. 4. This step tests for an internal fuel leak. If the fuel pressure drops during
this test, then an internal loss of pressure is indicated. 6. This step tests the fuel pressure regulator.
The fuel pressure regulator is controlled by the engine vacuum. With the engine vacuum applied,
the
pressure should drop to the specified value.
9. This step inspects the fuel pressure regulator for a fuel leak from the vacuum port. If fuel leaks
from the fuel pressure regulator while the fuel
pump is commanded ON, replace the fuel pressure regulator.
10. This step tests for a loss of fuel pressure between the fuel feed pipe shut-off adapter and the
fuel pump. 11. This step tests for a leaking fuel injector or for a leaking fuel pressure regulator. If
the fuel pressure remains constant during this test, the fuel
injectors are not leaking fuel.
14. This step tests for a restricted fuel return pipe. If the fuel pressure is within the specified values,
there is a restriction in the fuel return pipe. 16. This step determines if the fuel pressure regulator or
the fuel pump is the cause of the low fuel pressure. If the pressure rises above the specified
value, the fuel pump is OK.
18. This step verifies that a circuit condition is not the cause of a fuel pressure concern. Thoroughly
inspect all fuel electrical circuits.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Idle Speed > System
Information > Specifications
Idle Speed: Specifications
Idle Speed ...........................................................................................................................................
.............................................................. 500-700 rpm
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air
Cleaner Restriction Indicator > Component Information > Description and Operation
Air Cleaner Restriction Indicator: Description and Operation
Air Cleaner Restriction Indicator
The air cleaner restriction indicator is located on the air cleaner assembly between the air filter and
the mass air flow (MAF) sensor.
If the area inside of the clear section is green, no air filter service is required. If the area inside the
clear section is orange and Change Air Filter appears, replace the air filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: Customer Interest Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 2704
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: All Technical Service Bulletins Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 2710
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Page 2711
Air Filter Element: Service and Repair
AIR CLEANER ELEMENT REPLACEMENT
REMOVAL PROCEDURE
1. Remove the intake duct (2). 2. Disconnect the electrical connector from the mass air flow/intake
air temperature (MAF/IAT) sensor.
3. Loosen the 4 fasteners (8) securing the air cleaner housing top cover (4). 4. Lift and rotate the
top cover (4) of the air cleaner housing to gain access to the air filter element. 5. Lift out the air filter
element (5). 6. Inspect the air filter element for dust, dirt, or water. Clean or replace the air filter
element if required.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Page 2712
1. Install the air filter element (5) into the air cleaner housing. 2. Rotate and install the top cover (4)
to the air cleaner housing (6). 3. Insert the fasteners (8) to secure the top cover.
4. Connect the MAF/IAT electrical connector. 5. Install the intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Filter > Fuel Pressure
Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Fuel Filter > Fuel Pressure
Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal > Page 2718
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Ignition Cable > Component
Information > Specifications
Ignition System Specifications
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Ignition Cable > Component
Information > Service and Repair > Spark Plug Wire Inspection
Ignition Cable: Service and Repair Spark Plug Wire Inspection
Spark plug wire integrity is vital for proper engine operation. A thorough inspection will be
necessary to accurately identify conditions that may affect engine operation. Inspect for the
following conditions:
^ Correct routing of the spark plug wires-Incorrect routing may cause cross-firing.
^ Any signs of cracks or splits in the wires.
^ Inspect each boot for the following conditions: Tearing
- Piercing
- Arcing
- Carbon tracking
- Corroded terminal
If corrosion, carbon tracking or arcing are indicated on a spark plug wire boot or on a terminal,
replace the wire and the component connected to the wire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Ignition Cable > Component
Information > Service and Repair > Spark Plug Wire Inspection > Page 2724
Ignition Cable: Service and Repair Spark Plug Wire Replacement
REMOVAL PROCEDURE
1. Disconnect the spark plug wire at each spark plug.
^ Twist each spark plug 1/2 turn.
^ Pull only on the boot in order to remove the wire from each spark plug.
2. Disconnect the spark plug wire from the ignition coil.
^ Twist each spark plug boot 1/2 turn.
^ Pull only on the boot in order to remove the wires from the ignition coil.
SPARK PLUG WIRE LENGTH V8
Spark Plug Wire Length V8
^ The Melco(R), square design, uses a spark plug wire (1) that is 145 mm (5.70 in) length cable
seal to cable seal.
^ The Delphi(R), round design uses a spark plug wire (2) that is 110 mm (4.30 in) length cable seal
to cable seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Ignition Cable > Component
Information > Service and Repair > Spark Plug Wire Inspection > Page 2725
Ignition Coils
^ There are 2 different manufacturers for the ignition coils, the Melco(R) (1) square design, and the
Delphi(R) (2) round design. These 2 coils use 2 different spark plug wire, and mounting brackets.
^ Melco(R), square design, coil mounting bracket (1).
^ Delphi(R), round design, coil mounting bracket (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Ignition Cable > Component
Information > Service and Repair > Spark Plug Wire Inspection > Page 2726
1. Install the spark plug wires at the ignition coil. 2. Install the spark plug wire to each spark plug. 3.
Inspect the wires for proper installation:
^ Push sideways on each boot in order to inspect the seating.
^ Reinstall any loose boot.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Technical Service Bulletins > Ignition System - New Spark Plugs & Gapping Info.
Spark Plug: Technical Service Bulletins Ignition System - New Spark Plugs & Gapping Info.
INFORMATION
Bulletin No.: 03-06-04-060B
Date: July 30 2008
Subject: Information on New Spark Plugs and Gapping
Models
Attention:
Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACOelco(R)
Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
Supercede:
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard
Corporate Bulletin Number 03-06-04-060A (Section 06 - Engine/Propulsion System).
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the different tip design the gap of the spark
plug has also changed.
^ The new spark plug P/N 12571164 with AC Delco P/N 41-985 is gapped to 1.01 mm (0.040 in)
when the spark plug is made.
Notice:
The spark plug gap is set during manufacturing and should not be changed or damage to the spark
plug may result. Any new spark plug found to not be properly gapped should not be used.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Technical Service Bulletins > Page 2731
Spark Plug: Specifications
This article has been updated with TSB #03-06-04-060B
INFORMATION ON NEW SPARK PLUGS AND GAPPING
SPARK PLUG GAP..............................................................................................................................
.................................................. 1.01 mm (0.040 in.)
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the
different tip design, the gap of the spark plug has also changed.
^ The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040
inches) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to
the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Technical Service Bulletins > Page 2732
Spark Plug: Application and ID
AC Plug Type ......................................................................................................................................
................................................................... 25171803
NGK Plug Type ....................................................................................................................................
................................................................. 12567759
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Service and Repair > Spark Plug Inspection
Spark Plug: Service and Repair Spark Plug Inspection
SPARK PLUG USAGE
^ Verify that the correct spark plug is installed. An incorrect spark plug causes driveability
conditions. Refer to Ignition System Specifications for the correct spark plug.
^ Ensure that the spark plug has the correct heat range. An incorrect heat range causes the
following conditions: Spark plug fouling-Colder plug
- Pre-ignition causing spark plug and/or engine damage-Hotter plug
SPARK PLUG INSPECTION
^ Inspect the terminal P05 (1) for damage. Inspect for a bent or broken terminal post (1).
- Test for a loose terminal post (1) by twisting and pulling the post. The terminal post (1) should
NOT move.
^ Inspect the insulator (2) for flashover or carbon tracking, soot. This is caused by the electrical
charge traveling across the insulator (2) between the terminal post (1) and ground. Inspect for the
following conditions: Inspect the spark plug boot for damage.
- Inspect the spark plug recess area of the cylinder head for moisture, such as oil, coolant, or
water. A spark plug boot that is saturated causes arcing to ground.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Service and Repair > Spark Plug Inspection > Page 2735
^ Inspect the insulator (2) for cracks. All or part of the electrical charge may arc through the crack
instead of the electrodes (3, 4).
^ Inspect for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to
Ignition System Specifications. An excessively wide electrode gap can prevent correct spark plug
operation.
- Inspect for the correct spark plug torque. Refer to Ignition System Specifications. Insufficient
torque can prevent correct spark plug operation. An over torqued spark plug, causes the insulator
(2) to crack.
- Inspect for signs of tracking that occurred near the insulator tip instead of the center electrode (4).
- Inspect for a broken or worn side electrode (3).
- Inspect for a broken, worn, or loose center electrode (4) by shaking the spark plug. ^
A rattling sound indicates internal damage.
^ A loose center electrode (4) reduces the spark intensity.
- Inspect for bridged electrodes (3, 4). Deposits on the electrodes (3, 4) reduce or eliminates the
gap.
- Inspect for worn or missing platinum pads on the electrodes (3, 4), if equipped.
- Inspect for excessive fouling.
^ Inspect the spark plug recess area of the cylinder head for debris. Dirty or damaged threads can
cause the spark plug not to seat correctly during installation.
SPARK PLUG VISUAL INSPECTION
^ Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal
combustion by-products from fuels with additives.
^ Carbon fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures ^
Leaking fuel injectors
^ Excessive fuel pressure
^ Restricted air filter element
^ Incorrect combustion
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Service and Repair > Spark Plug Inspection > Page 2736
- Reduced ignition system voltage output ^
Weak coils
^ Worn ignition wires
^ Incorrect spark plug gap
- Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that
normal combustion deposits may not burn off.
^ Deposit fouling-Oil, coolant, or additives that include substances such as silicone, very white
coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless
they form into a glazing over the electrode.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Spark Plug > Component
Information > Service and Repair > Spark Plug Inspection > Page 2737
Spark Plug: Service and Repair Spark Plug Replacement
REMOVAL PROCEDURE
1. Remove the spark plug wires. 2. Loosen each spark plug 1 or 2 turns. 3. Brush or air blast away
any dirt from around the spark plugs. 4. Remove the spark plugs 1 at a time. Place each plug in a
tray marked with the corresponding cylinder numbers.
INSTALLATION PROCEDURE
1. Properly position each spark plug washer. 2. Inspect each spark plug gap. Adjust each plug as
needed.
Specification Spark plug gap: 1.52 mm (0.060 in)
NOTE: Refer to Fastener Notice in Service Precautions.
3. Hand start the spark plugs in the corresponding cylinders. 4. Tighten the spark plugs.
Tighten ^
For used heads tighten the spark plugs to 15 N.m (11 lb ft).
^ For new aluminum heads tighten the spark plugs to 20 N.m (15 lb ft).
^ For new iron heads, tighten the spark plugs to 30 N.m (22 lb ft).
5. Install the spark plug wires.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Compression Check > System
Information > Specifications
Compression Check: Specifications
The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure
in any one cylinder is 1035 kPa (150 psi), the lowest allowable pressure for any other cylinder
would be 725 kPa (105 psi). (1035 x 70% = 725) (150 x 70% = 105).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Compression Check > System
Information > System Diagnosis > Engine Compression Test (Electronic Throttle)
Compression Check: Testing and Inspection Engine Compression Test (Electronic Throttle)
Engine Compression Test (Electronic Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Turn the ignition to the ON position. 6.
Depress the accelerator pedal to position the throttle plate wide open. 7. Start with the compression
gauge at zero and crank the engine through four compression strokes, four puffs. 8. Check the
compression for each cylinder. Record the readings. 9. If a cylinder has low compression, inject
approximately 15 ml. (1 tablespoon) of engine oil into the combustion chamber through the spark
plug
hole. Recheck the compression and record the reading.
10. The minimum compression in any one cylinder should not be less than 70 percent of the
highest cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Then compression builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Compression Check > System
Information > System Diagnosis > Engine Compression Test (Electronic Throttle) > Page 2743
Compression Check: Testing and Inspection Engine Compression Test (Mechanical Throttle)
Engine Compression Test (Mechanical Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Block the throttle plate wide open. 6.
Start with the compression gauge at zero and crank the engine through four compression strokes,
four puffs. 7. Make the compression check for each cylinder. Record the reading. 8. If a cylinder
has low compression, inject approximately 15 ml. (1 tablespoon) of engine oil into the combustion
chamber through the spark plug
hole. Recheck the compression and record the reading.
9. The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Compression then builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Tune-up and Engine Performance Checks > Valve Clearance > System
Information > Specifications
Valve Clearance: Specifications
The manufacturer indicates that this vehicle has hydraulic lifters or adjusters and therefore does
not require adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins >
Customer Interest: > 01-02-32-007 > Sep > 01 > Accessory Drive Belt - Whining Type Noise
Drive Belt: Customer Interest Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics
Drive Belt: All Technical Service Bulletins Engine - Drive Belt Misalignment Diagnostics
INFORMATION
Bulletin No.: 08-06-01-008A
Date: July 27, 2009
Subject: Diagnosing Accessory Drive Belt / Serpentine Belt Noise and Availability and Use of
Kent-Moore EN-49228 Laser Alignment Tool - Drive Belt
Models:
2010 and Prior GM Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2,
H3 Vehicles 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add a model year and update the Tool Information.
Please discard Corporate Bulletin Number 08-06-01-008 (Section 06 - Engine).
Background
Several aftermarket companies offer laser alignment tools for accessory drive systems that can be
very helpful in eliminating drive belt noise as a result of misaligned pulleys. Typically pricing ranges
from $160 - $200.
EN-49228 Laser Alignment Tool - Drive Belt
The GM Tool program has now made available a competitive, simple to use and time-saving laser
tool to assist in achieving precise alignment of the drive belt pulleys. This optional tool removes the
guesswork from proper pulley alignment and may serve to reduce comebacks from:
- Drive Belt Noise
- Accelerated Drive Belt Wear
- Drive Belt Slippage
Instructions
The instructions below are specific only to the truck Gen IV V-8 family of engines. These
instructions are only for illustrative purposes to show how the tool may be used. Universal
instructions are included in the box with the Laser Alignment Tool - Drive Belt.
Caution
- Do not look directly into the beam projected from the laser.
- Use caution when shining the laser on highly polished or reflective surfaces. Laser safety glasses
help reduce laser beam glare in many circumstances.
- Always use laser safety glasses when using the laser. Laser safety glasses are not designed to
protect eyes from direct laser exposure.
1. Observe and mark the serpentine belt orientation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics >
Page 2760
2. Remove the serpentine belt from the accessory drive system.
3. Install the tool onto the power steering pulley. Position the legs of the tool into the outer grooves
of the pulley, farthest from the front of the
engine.
4. Install the retaining cord around the pulley and to the legs of the tool.
5. Put on the laser safety glasses provided with the tool. 6. Depress the switch on the rear of the
tool to activate the light beam. 7. Rotate the power steering pulley as required to project the light
beam onto the crankshaft balancer pulley grooves. 8. Inspect for proper power steering pulley
alignment.
- If the laser beam projects onto the second rib or raised area (1), the pulleys are aligned properly.
- If the laser beam projects more than one-quarter rib 0.9 mm (0.035 in) mis-alignment, adjust the
position of the power steering pulley as required.
- Refer to SI for Power Steering Pulley Removal and Installation procedures.
9. Install the serpentine belt to the accessory drive system in the original orientation.
10. Operate the vehicle and verify that the belt noise concern is no longer present.
Tool Information
Please visit the GM service tool website for pricing information or to place your order for this tool.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics >
Page 2761
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Drive Belt: > 04-06-01-013 > Apr > 04 > Engine - Serpentine Drive Belt Wear Information
Drive Belt: All Technical Service Bulletins Engine - Serpentine Drive Belt Wear Information
Bulletin No.: 04-06-01-013
Date: April 29, 2004
INFORMATION
Subject: Information on Serpentine Belt Wear
Models: 2004 and Prior Passenger Cars and Trucks 2003-2004 and Prior HUMMER H2
All current GM vehicles designed and manufactured in North America were assembled with
serpentine belts that are made with an EPDM material and should last the life of the vehicle. It is
extremely rare to observe any cracks in EPDM belts and it is not expected that they will require
maintenance before 10 years or 240,000 km (150,000 mi) of use.
Older style belts, which were manufactured with a chloroprene compound, may exhibit cracks
depending on age. However, the onset of cracking typically signals that the belt is only about
halfway through its usable life.
A good rule of thumb for chloroprene-based belts is that if cracks are observed 3 mm (1/8 in) apart,
ALL AROUND THE BELT, the belt may be reaching the end of its serviceable life and should be
considered a candidate for changing. Small cracks spaced at greater intervals should not be
considered as indicative that the belt needs changing.
Any belt that exhibits chunking should be replaced.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Drive Belt: > 01-02-32-007 > Sep > 01 > Accessory Drive Belt - Whining Type Noise
Drive Belt: All Technical Service Bulletins Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Other Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics
Drive Belt: All Technical Service Bulletins Engine - Drive Belt Misalignment Diagnostics
INFORMATION
Bulletin No.: 08-06-01-008A
Date: July 27, 2009
Subject: Diagnosing Accessory Drive Belt / Serpentine Belt Noise and Availability and Use of
Kent-Moore EN-49228 Laser Alignment Tool - Drive Belt
Models:
2010 and Prior GM Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2,
H3 Vehicles 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add a model year and update the Tool Information.
Please discard Corporate Bulletin Number 08-06-01-008 (Section 06 - Engine).
Background
Several aftermarket companies offer laser alignment tools for accessory drive systems that can be
very helpful in eliminating drive belt noise as a result of misaligned pulleys. Typically pricing ranges
from $160 - $200.
EN-49228 Laser Alignment Tool - Drive Belt
The GM Tool program has now made available a competitive, simple to use and time-saving laser
tool to assist in achieving precise alignment of the drive belt pulleys. This optional tool removes the
guesswork from proper pulley alignment and may serve to reduce comebacks from:
- Drive Belt Noise
- Accelerated Drive Belt Wear
- Drive Belt Slippage
Instructions
The instructions below are specific only to the truck Gen IV V-8 family of engines. These
instructions are only for illustrative purposes to show how the tool may be used. Universal
instructions are included in the box with the Laser Alignment Tool - Drive Belt.
Caution
- Do not look directly into the beam projected from the laser.
- Use caution when shining the laser on highly polished or reflective surfaces. Laser safety glasses
help reduce laser beam glare in many circumstances.
- Always use laser safety glasses when using the laser. Laser safety glasses are not designed to
protect eyes from direct laser exposure.
1. Observe and mark the serpentine belt orientation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Other Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page
2775
2. Remove the serpentine belt from the accessory drive system.
3. Install the tool onto the power steering pulley. Position the legs of the tool into the outer grooves
of the pulley, farthest from the front of the
engine.
4. Install the retaining cord around the pulley and to the legs of the tool.
5. Put on the laser safety glasses provided with the tool. 6. Depress the switch on the rear of the
tool to activate the light beam. 7. Rotate the power steering pulley as required to project the light
beam onto the crankshaft balancer pulley grooves. 8. Inspect for proper power steering pulley
alignment.
- If the laser beam projects onto the second rib or raised area (1), the pulleys are aligned properly.
- If the laser beam projects more than one-quarter rib 0.9 mm (0.035 in) mis-alignment, adjust the
position of the power steering pulley as required.
- Refer to SI for Power Steering Pulley Removal and Installation procedures.
9. Install the serpentine belt to the accessory drive system in the original orientation.
10. Operate the vehicle and verify that the belt noise concern is no longer present.
Tool Information
Please visit the GM service tool website for pricing information or to place your order for this tool.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Other Service Bulletins for Drive Belt: > 08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page
2776
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Technical Service Bulletins > All
Other Service Bulletins for Drive Belt: > 04-06-01-013 > Apr > 04 > Engine - Serpentine Drive Belt Wear Information
Drive Belt: All Technical Service Bulletins Engine - Serpentine Drive Belt Wear Information
Bulletin No.: 04-06-01-013
Date: April 29, 2004
INFORMATION
Subject: Information on Serpentine Belt Wear
Models: 2004 and Prior Passenger Cars and Trucks 2003-2004 and Prior HUMMER H2
All current GM vehicles designed and manufactured in North America were assembled with
serpentine belts that are made with an EPDM material and should last the life of the vehicle. It is
extremely rare to observe any cracks in EPDM belts and it is not expected that they will require
maintenance before 10 years or 240,000 km (150,000 mi) of use.
Older style belts, which were manufactured with a chloroprene compound, may exhibit cracks
depending on age. However, the onset of cracking typically signals that the belt is only about
halfway through its usable life.
A good rule of thumb for chloroprene-based belts is that if cracks are observed 3 mm (1/8 in) apart,
ALL AROUND THE BELT, the belt may be reaching the end of its serviceable life and should be
considered a candidate for changing. Small cracks spaced at greater intervals should not be
considered as indicative that the belt needs changing.
Any belt that exhibits chunking should be replaced.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping
Drive Belt: Testing and Inspection Drive Belt Chirping
Drive Belt Chirping Diagnosis
Drive Belt Chirping Diagnosis
Diagnostic Aids
The chirping noise may be intermittent due to moisture on the drive belt(s) or the accessory drive
pulley(s). In order to duplicate the customers concern, it may be necessary to spray a small amount
of water onto the drive belt(s). If spraying water onto the drive belt(s) duplicates the symptom,
cleaning the accessory drive pulley(s) may be the most probable solution. A loose or improper
installation of a body or suspension component, or other item(s) on the vehicle may also cause the
chirping noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The chirping noise may not be
engine related. This step is to verify that the engine is making the noise. It the engine is not making
the noise do not
proceed any further in this table.
3. The noise may be an internal engine noise. Remove the drive belt(s) and operate the engine for
a few seconds, this will verify if the chirping noise
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2783
is related to the drive belt(s) or not. With the drive belt(s) removed the water pump will not operate
and the engine may overheat. Also diagnostic trouble codes (DTCs) may set when the engine is
operated with the drive belt(s) removed.
4. Inspect the drive belt(s) for signs of pilling. Pilling is the small balls, pills, or strings in the drive
belt grooves caused by the accumulation of
rubber dust.
6. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of an accessory drive component,
or the pulley may be bent inward or outward from a previous repair. Test for a misaligned
accessory drive pulley using a straight edge in the pulley grooves across two or three pulleys. If a
misaligned pulley is found, refer to that accessory drive component for the proper removal and
installation procedure for that pulley.
10. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or
washer was installed. 12. Inspection of the accessory drive pulley(s) should include inspecting for
bends, dents, or other damage to the pulley(s) that would prevent the drive
belt(s) from seating properly in the pulley grooves or on the smooth surface of the pulley when the
back side of the drive belt is used to drive the pulley.
14. Replacing the drive belt(s) when it is not damaged or there is not excessive pilling will only be a
temporary repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2784
Drive Belt: Testing and Inspection Drive Belt Excessive Wear
Drive Belt Excessive Wear Diagnosis
Drive Belt Excessive Wear Diagnosis
Diagnostic Aids
Excessive wear on a drive belt(s) is usually caused by incorrect installation or the incorrect drive
belt(s) for the application. Minor misalignment of the accessory drive pulley(s) will not cause
excessive wear, but will probably cause the drive belt(s) to make a noise or fall off. Excessive
misalignment of the accessory drive pulley(s) will cause excessive wear and may also make the
drive belt(s) fall off.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify that
the drive belt(s) is correctly installed on all of the accessory drive pulleys. Wear on the drive belt(s)
may be caused
by mix-positioning the drive belt(s) by one or more grooves on a pulley(s).
3. The installation of a drive belt(s) that is too wide or too narrow will cause wear on the drive
belt(s). The drive belt(s) ribs should match all of the
grooves on the pulleys.
4. This inspection is to verify that the drive belt(s) is not contacting any part of the engine or body
while the engine is operating. There should be
sufficient clearance when the accessory drive components load varies. The drive belt(s) should not
come in contact with an engine or a body component when snapping the throttle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2785
Drive Belt: Testing and Inspection Drive Belt Falls Off
Drive Belt Falls Off Diagnosis
Drive Belt Falls Off Diagnosis
Diagnostic Aids
If the drive belt(s) repeatedly falls off the accessory drive pulley(s), this may be caused by a pulley
misalignment. An extra load that is quickly applied or released by an accessory drive component
may also cause the drive belt(s) to fall off. Verify that the accessory drive component(s) are
operating properly. If the drive belt(s) is the incorrect length, the drive belt tensioner may not
maintain the proper tension on the drive belt(s).
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify the
condition of the drive belt(s). Damage may have occurred to the drive belt(s) when the drive belt(s)
fell off the
pulley. Inspect the drive belt(s) for cuts, tears, sections of ribs missing, or damaged belt plys.
4. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure of that
pulley.
5. Inspection of the accessory drive pulley(s) should include inspecting for bends, dents, or other
damage that would prevent the drive belt from
seating properly in the pulley grooves or on the smooth surface of a pulley when the back side of
the drive belt(s) is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belt(s) to
fall off. 7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer,
or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive bracket(s) moving under load.
Over tightening the fasteners may cause misalignment of the accessory component bracket(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2786
Drive Belt: Testing and Inspection Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a component or another part of the vehicle to make
rumbling noise. The drive belt(s) may have a condition that can not be seen or felt. Sometimes
replacing the drive belt(s) may be the only repair for the symptom. If after replacing the drive belt(s)
and completing the diagnostic table, the rumbling is only heard with the drive belt(s) installed, there
might be an accessory drive component failure. Varying the load on the accessory drive
component(s) may aid in identifying which component is causing the rumbling noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
symptom is present during diagnosing. Other vehicle components may cause a similar symptom. 3.
This test is to verify that the drive belt(s) is causing the rumbling. Rumbling may be confused with
an internal engine noise due to the similarity in
the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. Operate
the engine for a few seconds, this will verify if the rumbling noise is related to the drive belt(s) or
not. With the drive belt(s) removed the water pump will not operate and the engine may overheat.
Also diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. Inspect the drive belt(s) to ensure that the drive belt(s) is not the cause of the noise. Small
cracks across the fibs of the drive belt(s) will not cause
the noise. Belt separation is identified by the plys of the belt separating, this may be seen at the
edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and acceptable. When the pilling is severe the
drive belt(s) does not have a smooth surface for
proper operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2787
Drive Belt: Testing and Inspection
Drive Belt Chirping
Drive Belt Chirping Diagnosis
Drive Belt Chirping Diagnosis
Diagnostic Aids
The chirping noise may be intermittent due to moisture on the drive belt(s) or the accessory drive
pulley(s). In order to duplicate the customers concern, it may be necessary to spray a small amount
of water onto the drive belt(s). If spraying water onto the drive belt(s) duplicates the symptom,
cleaning the accessory drive pulley(s) may be the most probable solution. A loose or improper
installation of a body or suspension component, or other item(s) on the vehicle may also cause the
chirping noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The chirping noise may not be
engine related. This step is to verify that the engine is making the noise. It the engine is not making
the noise do not
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2788
proceed any further in this table.
3. The noise may be an internal engine noise. Remove the drive belt(s) and operate the engine for
a few seconds, this will verify if the chirping noise
is related to the drive belt(s) or not. With the drive belt(s) removed the water pump will not operate
and the engine may overheat. Also diagnostic trouble codes (DTCs) may set when the engine is
operated with the drive belt(s) removed.
4. Inspect the drive belt(s) for signs of pilling. Pilling is the small balls, pills, or strings in the drive
belt grooves caused by the accumulation of
rubber dust.
6. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of an accessory drive component,
or the pulley may be bent inward or outward from a previous repair. Test for a misaligned
accessory drive pulley using a straight edge in the pulley grooves across two or three pulleys. If a
misaligned pulley is found, refer to that accessory drive component for the proper removal and
installation procedure for that pulley.
10. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or
washer was installed. 12. Inspection of the accessory drive pulley(s) should include inspecting for
bends, dents, or other damage to the pulley(s) that would prevent the drive
belt(s) from seating properly in the pulley grooves or on the smooth surface of the pulley when the
back side of the drive belt is used to drive the pulley.
14. Replacing the drive belt(s) when it is not damaged or there is not excessive pilling will only be a
temporary repair.
Drive Belt Excessive Wear
Drive Belt Excessive Wear Diagnosis
Drive Belt Excessive Wear Diagnosis
Diagnostic Aids
Excessive wear on a drive belt(s) is usually caused by incorrect installation or the incorrect drive
belt(s) for the application. Minor misalignment of the accessory drive pulley(s) will not cause
excessive wear, but will probably cause the drive belt(s) to make a noise or fall off. Excessive
misalignment of the accessory drive pulley(s) will cause excessive wear and may also make the
drive belt(s) fall off.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify that
the drive belt(s) is correctly installed on all of the accessory drive pulleys. Wear on the drive belt(s)
may be caused
by mix-positioning the drive belt(s) by one or more grooves on a pulley(s).
3. The installation of a drive belt(s) that is too wide or too narrow will cause wear on the drive
belt(s). The drive belt(s) ribs should match all of the
grooves on the pulleys.
4. This inspection is to verify that the drive belt(s) is not contacting any part of the engine or body
while the engine is operating. There should be
sufficient clearance when the accessory drive components load varies. The drive belt(s) should not
come in contact with an engine or a body component when snapping the throttle.
Drive Belt Falls Off
Drive Belt Falls Off Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2789
Drive Belt Falls Off Diagnosis
Diagnostic Aids
If the drive belt(s) repeatedly falls off the accessory drive pulley(s), this may be caused by a pulley
misalignment. An extra load that is quickly applied or released by an accessory drive component
may also cause the drive belt(s) to fall off. Verify that the accessory drive component(s) are
operating properly. If the drive belt(s) is the incorrect length, the drive belt tensioner may not
maintain the proper tension on the drive belt(s).
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify the
condition of the drive belt(s). Damage may have occurred to the drive belt(s) when the drive belt(s)
fell off the
pulley. Inspect the drive belt(s) for cuts, tears, sections of ribs missing, or damaged belt plys.
4. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure of that
pulley.
5. Inspection of the accessory drive pulley(s) should include inspecting for bends, dents, or other
damage that would prevent the drive belt from
seating properly in the pulley grooves or on the smooth surface of a pulley when the back side of
the drive belt(s) is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belt(s) to
fall off. 7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer,
or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive bracket(s) moving under load.
Over tightening the fasteners may cause misalignment of the accessory component bracket(s).
Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2790
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a component or another part of the vehicle to make
rumbling noise. The drive belt(s) may have a condition that can not be seen or felt. Sometimes
replacing the drive belt(s) may be the only repair for the symptom. If after replacing the drive belt(s)
and completing the diagnostic table, the rumbling is only heard with the drive belt(s) installed, there
might be an accessory drive component failure. Varying the load on the accessory drive
component(s) may aid in identifying which component is causing the rumbling noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
symptom is present during diagnosing. Other vehicle components may cause a similar symptom. 3.
This test is to verify that the drive belt(s) is causing the rumbling. Rumbling may be confused with
an internal engine noise due to the similarity in
the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. Operate
the engine for a few seconds, this will verify if the rumbling noise is related to the drive belt(s) or
not. With the drive belt(s) removed the water pump will not operate and the engine may overheat.
Also diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. Inspect the drive belt(s) to ensure that the drive belt(s) is not the cause of the noise. Small
cracks across the fibs of the drive belt(s) will not cause
the noise. Belt separation is identified by the plys of the belt separating, this may be seen at the
edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and acceptable. When the pilling is severe the
drive belt(s) does not have a smooth surface for
proper operation.
Drive Belt Squeal
Drive Belt Squeal Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2791
Drive Belt Squeal Diagnosis
Diagnostic Aids
A loose or improper installation of a body, or suspension component, or other item(s) on the vehicle
may cause the squeal noise. If the squeal is intermittent, verify that it is not the accessory drive
component(s) by varying their load(s), making sure they are operating to their maximum capacity.
An overcharged air conditioning (A/C) system, a power steering system restriction or the incorrect
fluid, or a failing generator are suggested items to inspect.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The squeal may not be engine
related. This step is to verify that the engine is making the noise. If the engine is not making the
noise do not
proceed further in this table.
3. The squeal may be an internal engine noise. Remove the drive belt(s) and operate the engine
for a few seconds, this will verify if the squealing
noise is related to the drive belt(s) or an accessory drive component. With the drive belt(s) removed
the water pump will not operate and the engine may overheat. Also diagnostic trouble codes
(DTCs) may set when the engine is operated with the drive belt(s) removed.
4. This test is to verify that an accessory drive component(s) does not have a seized bearing. With
the belt(s) removed, test the bearings in the
accessory drive component(s) for smooth operation. Also test the accessory drive component(s)
with the engine operating by varying the load on the accessory drive component(s) to verify that the
component(s) is operating properly.
5. This test is to verify that the drive belt(s) tensioner(s) are not operating properly. If the drive belt
tensioner(s) are not operating properly, proper
belt tension may not be achieved to keep the drive belt(s) from slipping which could cause a
squealing noise.
6. This test is to verify that the drive belt(s) is not too long, which would prevent the drive belt
tensioner(s) from operating properly. Also if the
incorrect length drive belt(s) was installed, it may not be routed correctly and may be turning an
accessory drive component in the incorrect direction.
7. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure for that
pulley.
8. Inspect the accessory drive pulley(s) to verify that they are the correct diameter or width. Using a
known good vehicle, compare the accessory
drive pulleys.
Drive Belt Vibration
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2792
Drive Belt Vibration Diagnosis
Drive Belt Vibration Diagnosis
Diagnostic Aids
The accessory drive components may have an affect on engine vibration. An overcharged air
conditioning (A/C) system, a power steering system restriction, or the incorrect fluid, or an extra
load placed on the generator are suggested items to inspect. To help identify an intermittent or an
improper condition, vary the loads on the accessory drive components.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
vibration is present during diagnosing. Other vehicle components may cause a similar symptom
such as the exhaust
system, or the drivetrain.
3. This test is to verify that the drive belt(s) or accessory drive components may be causing the
vibration. Remove the drive belt(s) and operate the
engine for a few seconds, this will verify if the vibration is related to the drive belt(s) or not. With the
drive belt(s) removed the water pump will not operate and the engine may overheat. Also
diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. The drive belt(s) may cause a vibration. While the drive belt(s) is removed this is the best time to
inspect the condition of the drive belt(s). 6. Inspection of the fasteners can eliminate the possibility
that a incorrect bolt, nut, spacer, or washer was installed. 8. This step should only be performed if
the fan is driven by the drive belt. Inspect the engine cooling fan for bent, twisted, loose, or cracked
blades.
Inspect the fan clutch for smooth operation. Inspect for a bent fan shaft or bent mounting flange.
9. Inspect the water pump drive shaft for being bent. Also inspect the water pump bearings for
smooth operation and excessive play. Compare the
water pump with a known, good water pump.
10. Accessory drive component brackets that are bent, cracked, or loose may put an extra strain on
that accessory drive component causing it to
vibrate.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Testing and Inspection > Drive Belt
Chirping > Page 2793
Drive Belt Whine
Drive Belt Whine Diagnosis
Drive Belt Whine Diagnosis
Diagnostic Aids
The drive belt(s) will not cause the whine. If the whine is intermittent, verify that it is not the
accessory drive component(s) by varying their loads, making sure they are operating to their
maximum capacity. An overcharged air conditioning (A/C) system, a power steering system
restriction or the incorrect fluid, or a failing generator are suggested items to inspect.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 3. This test is to verify that the
whine is being caused by the accessory drive component(s). Remove the drive belt(s) and operate
the engine for a
few seconds this will verify if the whining noise is related to the accessory drive component. With
the drive belt(s) removed the water pump will not operate and the engine may overheat. Also
diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. This inspection should include checking the drive belt tensioner and the drive belt idler pulley
bearings. The drive belt(s) may have to be installed
and the accessory drive components operated separately by varying their loads. Refer to the
suspected accessory drive component for the proper removal and installation procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Service and Repair > Accessory
Drive Belt Replacement
Drive Belt: Service and Repair Accessory Drive Belt Replacement
Drive Belt Replacement - Accessory
Removal Procedure
1. Loosen the air cleaner outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
2. Remove the radiator inlet hose clip from the outlet duct. 3. Remove the air cleaner outlet duct.
4. Install a breaker bar with hex-head socket to the drive belt tensioner bolt. 5. Rotate the drive belt
tensioner clockwise in order to relieve tension on the belt. 6. Remove the belt from the pulleys and
the drive belt tensioner. 7. Slowly release the tension on the drive belt tensioner. 8. Remove the
breaker bar and socket and from the drive belt tensioner bolt. 9. Clean and inspect the belt
surfaces of all the pulleys.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Service and Repair > Accessory
Drive Belt Replacement > Page 2796
1. Route the drive belt around all the pulleys except the idler pulley. 2. Install the breaker bar with
hex-head socket to the belt tensioner bolt. 3. Rotate the belt tensioner clockwise in order to relieve
the tension on the tensioner. 4. Install the drive belt under the idler pulley. 5. Slowly release the
tension on the belt tensioner. 6. Remove the breaker bar and socket from the belt tensioner bolt. 7.
Inspect the drive belt for proper installation and alignment.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
8. Install the air cleaner outlet duct. 9. Install the radiator inlet hose clip to the outlet duct.
Notice: Refer to Fastener Notice in Service Precautions.
10. Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Service and Repair > Accessory
Drive Belt Replacement > Page 2797
Drive Belt: Service and Repair A/C Belt
Drive Belt Replacement - Air Conditioning
Removal Procedure
1. Remove the accessory drive belt. 2. Raise and suitably support the vehicle. Refer to Vehicle
Lifting. 3. Remove the engine shield bolts. 4. Remove the engine shield.
5. Install a ratchet into the air conditioning (A/C) belt tensioner adapter opening. 6. Rotate the A/C
belt tensioner clockwise in order to relieve tension on the belt. 7. Remove the A/C belt from the
pulleys. 8. Slowly release the tension on the A/C belt tensioner. 9. Remove the ratchet from the
A/C belt tensioner.
10. Clean and inspect the belt surfaces of all the pulleys.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Drive Belt > Component Information > Service and Repair > Accessory
Drive Belt Replacement > Page 2798
1. Install the A/C belt around the crankshaft balancer. 2. Install a ratchet into the A/C drive belt
tensioner adapter opening 3. Rotate the A/C belt tensioner clockwise in order to relieve tension on
the tensioner. 4. Install the A/C belt over the idler pulley. 5. Install the A/C belt around the A/C
compressor pulley. 6. Slowly release the tension on the A/C belt tensioner. 7. Remove the ratchet
from the A/C belt tensioner. 8. Inspect the A/C belt for proper installation and alignment.
9. Install the engine shield.
Notice: Refer to Fastener Notice in Service Precautions.
10. Install the engine shield bolts.
- Tighten the engine shield bolts to 20 Nm (15 ft. lbs.).
11. Lower the vehicle. 12. Install the accessory drive belt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Cleaner Restriction Indicator >
Component Information > Description and Operation
Air Cleaner Restriction Indicator: Description and Operation
Air Cleaner Restriction Indicator
The air cleaner restriction indicator is located on the air cleaner assembly between the air filter and
the mass air flow (MAF) sensor.
If the area inside of the clear section is green, no air filter service is required. If the area inside the
clear section is orange and Change Air Filter appears, replace the air filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > Customer Interest for Air Filter Element: > 04-07-30-013B > Feb > 07 > Engine, A/T Shift/Driveability Concerns/MIL ON
Air Filter Element: Customer Interest Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > Customer Interest for Air Filter Element: > 04-07-30-013B > Feb > 07 > Engine, A/T Shift/Driveability Concerns/MIL ON > Page 2812
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: > 04-07-30-013B > Feb > 07 > Engine,
A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: All Technical Service Bulletins Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: > 04-07-30-013B > Feb > 07 > Engine,
A/T - Shift/Driveability Concerns/MIL ON > Page 2818
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > Page 2819
Air Filter Element: Service and Repair
AIR CLEANER ELEMENT REPLACEMENT
REMOVAL PROCEDURE
1. Remove the intake duct (2). 2. Disconnect the electrical connector from the mass air flow/intake
air temperature (MAF/IAT) sensor.
3. Loosen the 4 fasteners (8) securing the air cleaner housing top cover (4). 4. Lift and rotate the
top cover (4) of the air cleaner housing to gain access to the air filter element. 5. Lift out the air filter
element (5). 6. Inspect the air filter element for dust, dirt, or water. Clean or replace the air filter
element if required.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Air Cleaner Housing > Air Filter Element > Component Information
> Technical Service Bulletins > Page 2820
1. Install the air filter element (5) into the air cleaner housing. 2. Rotate and install the top cover (4)
to the air cleaner housing (6). 3. Insert the fasteners (8) to secure the top cover.
4. Connect the MAF/IAT electrical connector. 5. Install the intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Cabin Air Filter > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Cabin Air Filter > Component Information > Locations > Page 2824
Cabin Air Filter: Service and Repair
REMOVAL PROCEDURE
1. If equipped, remove the Instrument Panel (I/P) sound insulator. 2. Remove the filter access door
screw. 3. Remove the filter access door (1) from the HVAC module. 4. Remove the passenger
compartment air filter (2).
INSTALLATION PROCEDURE
1. Install the passenger compartment air filter (2).
2. Install the filter access door (1) to the HVAC module.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the filter access door screw.
Tighten Tighten The Screw to 1.6 Nm (14 lb in).
4. If equipped, install the I/P sound insulator.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E
Fluid Filter - A/T: Service and Repair 4L60-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
Caution: When the transmission is at operating temperatures, take necessary precautions when
removing the drain plug, to avoid being burned by draining field.
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the
transmission oil pan. 3. Remove the oil pan drain plug, if equipped. 4. If necessary, remove the
bolts and position aside the range selector cable bracket for clearance while lowering the pan. It is
not necessary to
remove the cable from the lever or bracket.
5. Remove the oil pan bolts from the front and sides of the pan only. 6. Loosen the rear oil pan
bolts approximately 4 turns. 7. Lightly tap the oil pan with a rubber mallet in order to loosen the pan
to allow the fluid to drain.
8. Remove the remaining oil pan bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E > Page 2829
9. Remove the oil pan and the gasket.
10. Grasp firmly while pulling down with a twisting motion in order to remove the filter.
11. Remove the filter seal. The filter seal may be stuck in the pump; if necessary, carefully use
pliers or another suitable tool to remove the seal. 12. Discard the seal. 13. Inspect the fluid color.
14. Inspect the filter. Pry the metal crimping away from the top of the filter and pull apart. The filter
may contain the following evidence for root cause
diagnosis: ^
Clutch material
^ Bronze slivers indicating bushing wear
^ Steel particles
15. Clean the transmission case and the oil pan gasket surfaces with solvent, and air dry. You must
remove all traces of the old gasket material.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E > Page 2830
1. Coat the new filter seal with automatic transmission fluid. 2. Install the new filter seal into the
transmission case. Tap the seal into place using a suitable size socket. 3. Install the new filter into
the case.
4. Install the oil pan and a new gasket.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan bolts.
^ Tighten the oil pan to transmission case bolts alternately and evenly to 11 Nm (97 inch lbs.).
6. If previously removed, install the range selector cable bracket and bolts.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Apply a small amount of sealant GM P/N 12346004 to the threads of the oil pan drain plug, if
equipped. 8. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E > Page 2831
9. Lower the vehicle.
10. Fill the transmission to the proper level with DEXRON III transmission fluid. 11. Check the
COLD fluid level reading for initial fill only. 12. Inspect the oil pan gasket for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E > Page 2832
Fluid Filter - A/T: Service and Repair 4L80-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the transmission oil pan. 3.
Remove the oil pan drain plug, if equipped. 4. Remove the oil pan bolts. 5. Remove the oil pan. 6.
Remove the gasket. 7. Remove the magnet.
8. Remove the oil filter. 9. Remove the filter neck seal.
10. The transmission oil pan gasket is reusable. Inspect the gasket and replace as needed. 11.
Clean the transmission case and the oil pan gasket surfaces with solvent.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fluid Filter - A/T > Component Information > Service and Repair >
4L60-E > Page 2833
1. Install the filter neck seal. 2. Install the oil filter.
3. Install the oil pan gasket to the pan. 4. Install the magnet into the bottom of the pan.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan to the transmission with seventeen bolts.
^ Tighten the oil pan bolts to 11 Nm (97 inch lbs.).
6. Apply a small amount of sealant GM P/N 12346004 to the treads of the drain plug, if equipped.
7. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
8. Lower the vehicle. 9. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fuel Filter > Fuel Pressure Release > System Information >
Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fuel Filter > Fuel Pressure Release > System Information >
Service and Repair > Fuel Pressure Gage Installation and Removal > Page 2839
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Fuel Pump Pickup Filter > Component Information > Description
and Operation
Fuel Pump Pickup Filter: Description and Operation
FUEL STRAINER
The fuel strainer attaches to the lower end of the fuel sender. The fuel strainer is made of woven
plastic. The functions of the fuel strainer are to filter contaminants and to wick fuel. The fuel strainer
is self-cleaning and normally requires no maintenance. Fuel stoppage at this point indicates that
the fuel tank contains an abnormal amount of sediment or water.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Technical Service
Bulletins > Engine - Noise/Damage Oil Filter Application Importance
Oil Filter: Technical Service Bulletins Engine - Noise/Damage Oil Filter Application Importance
INFORMATION
Bulletin No.: 07-06-01-016B
Date: July 27, 2009
Subject: Information on Internal Engine Noise or Damage After Oil Filter Replacement
Models:
2010 and Prior Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2, H3
2009 and Prior Saab 9-7X
Supercede: This bulletin is being updated to add model years. Please discard Corporate Bulletin
Number 07-06-01-016A (Section 06 - Engine/Propulsion System).
Important Engine damage that is the result of an incorrect or improperly installed engine oil filter is
not a warrantable claim. The best way to avoid oil filter quality concerns is to purchase ACDelco(R)
oil filters directly from GMSPO.
Oil filter misapplication may cause abnormal engine noise or internal damage. Always utilize the
most recent parts information to ensure the correct part number filter is installed when replacing oil
filters. Do not rely on physical dimensions alone. Counterfeit copies of name brand parts have been
discovered in some aftermarket parts systems. Always ensure the parts you install are from a
trusted source. Improper oil filter installation may result in catastrophic engine damage.
Refer to the appropriate Service Information (SI) installation instructions when replacing any oil
filter and pay particular attention to procedures for proper cartridge filter element alignment. If the
diagnostics in SI (Engine Mechanical) lead to the oil filter as the cause of the internal engine noise
or damage, dealers should submit a field product report. Refer to Corporate Bulletin Number
02-00-89-002I (Information for Dealers on How to Submit a Field Product Report).
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Specifications >
Mechanical Specifications
Oil Filter: Mechanical Specifications
Fastener Tightening Specifications
Oil Filter ...............................................................................................................................................
.................................................... 30 Nm (22 ft. lbs.) Oil Filter Fitting ..................................................
....................................................................................................................................... 55 Nm (40 ft.
lbs.)
Engine Mechanical Specifications (5.3L Engine)
Oil Filter Type ......................................................................................................................................
......................................................................... PF59
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Specifications >
Mechanical Specifications > Page 2849
Oil Filter: Capacity Specifications
Oil Capacity
With Filter Change ...............................................................................................................................
......................................... 5.68 Liters (6.0 Quarts) Without Filter Change ..........................................
........................................................................................................................ 4.73 Liters (5.0 Quarts)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Specifications >
Mechanical Specifications > Page 2850
Oil Filter: Fluid Type Specifications
Oil Type ...............................................................................................................................................
....................................................................... 5W-30
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Specifications > Page
2851
Oil Filter: Service and Repair
Engine Oil and Oil Filter Replacement
Removal Procedure
Important: In order to completely drain the oil from the oil pan internal baffling, the bottom of the oil
pan must be level during the oil drain procedure.
1. Open the hood. 2. Remove the oil fill cap. 3. Raise and suitably support the vehicle. Refer to
Vehicle Lifting. 4. Place a oil drain pan under the oil pan drain plug. 5. Remove the oil pan drain
plug. 6. Drain the engine oil. 7. Wipe the excess oil from the drain plug hole and plug.
8. Remove the oil filter from the engine block.
Important: Check the old oil filter to ensure that the filter seal is not left on the engine block.
9. Wipe the excess oil from the oil filter mounting.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Oil Filter, Engine > Component Information > Specifications > Page
2852
1. Lubricate the oil filter seal with clean engine oil.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the oil filter to the engine block.
- Tighten the oil filter to 30 Nm (22 ft. lbs.).
3. install the oil drain plug to the engine block.
- Tighten the oil pan drain plug to 25 Nm (18 ft. lbs.).
4. Lower the vehicle. 5. Fill the crankcase with the proper quantity and grade of engine oil. 6.
Remove the oil level indicator. 7. Wipe the indicator with a clean cloth. 8. Install the oil level
indicator. 9. Remove the oil level indicator in order to check the level.
10. Add oil if necessary: 11. Close the hood.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Technical Service
Bulletins > Customer Interest for Refrigerant Filter: > 03-01-38-019A > Sep > 04 > A/C - Underhood Rattle Noise on Hard
Acceleration
Refrigerant Filter: Customer Interest A/C - Underhood Rattle Noise on Hard Acceleration
File In Section: 01 - HVAC
Bulletin No.: 03-01-38~019A
Date: September, 2004
TECHNICAL
Subject: Underhood Rattle Noise Heard On Acceleration (Check A/C System Performance and
Compressor Operation)
Models: 2003-2004 Cadillac CTS 2002-2004 Cadillac Escalade, Escalade EXT 2003-2004 Cadillac
Escalade ESV 2002-2004 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe 2002-2004
GMC Denali, Denali XL, Savana, Sierra, Yukon, Yukon XL 2002-2004 Commercial Upfitter Chassis
Vehicles
with Air Conditioning (A/C)
This bulletin is being revised to update the service procedure and parts information. Please discard
Corporate Bulletin Number 03-01-38-019 (Section 01 - HVAC).
Condition
Some customers may comment about an underhood rattle noise heard on acceleration or a sudden
loss of A/C system performance.
Cause
This condition may be caused by liquid slugging of the A/C compressor. This condition may cause
an internal failure in the A/C compressor. The serpentine belt tensioner and serpentine belt may
also be damaged.
Correction
Technicians are to check the A/C system performance and compressor operation using the
following repair procedure:
1. Open the hood and inspect the A/C compressor for damage and to see if the compressor is
seized. Verify that the serpentine belt is not damaged or missing. If the A/C compressor is seized,
proceed to Step 5.
2. Perform the A/C System Performance test. Refer to the Heating, Ventilation and Air Conditioning
(HVAC) section of SI. Correct any performance concerns or refrigerant leaks that are found.
3. Inspect the vehicle for other possible sources of A/C compressor noise or performance
concerns. Refer to Corporate Bulletin Number 01-01-38-013 for more information.
4. After all other possible sources of A/C compressor noise or performance concerns have been
eliminated, only then should the A/C compressor be replaced.
5. Remove the A/C compressor. Refer to the A/C Compressor Replacement procedure in the
HVAC section of SI.
6. Inspect the transmission cooler lines for damage due to contact from the serpentine belt.
Replace the transmission cooler lines if necessary.
7. Install an inline A/C system filter. Refer to Corporate Bulletin Number 01-01-38-006C for more
information about A/C system flushing and filter installation procedures. An A/C system flush is not
to be done unless prior authorization is given by the GM Area Service Manager (in Canada, the
District Service Manager).
8. Install an A/C Suction Screen. Refer to Corporate Bulletin Number 01-01-39-003A for more
information about A/C suction screen repair recommendations and procedures.
9. Install a new A/C compressor. Refer to the Compressor Replacement procedure in the HVAC
section of SI.
10. Install a new orifice tube for the front A/C system. Refer to the Expansion (Orifice) Tube
Replacement procedure in SI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Technical Service
Bulletins > Customer Interest for Refrigerant Filter: > 03-01-38-019A > Sep > 04 > A/C - Underhood Rattle Noise on Hard
Acceleration > Page 2861
11. If the vehicle is a 2003 model year Chevrolet Express or GMC Savana van, the vehicle may
require a new accumulator. Refer to Corporate Bulletin Number 03-01-38-016 for more information.
This bulletin refers to an updated design accumulator that may improve the performance of the A/C
system.
12. Install a new serpentine belt tensioner and serpentine belt if they have been damaged due to
A/C system slugging or an A/C compressor seizure. The serpentine belt tensioner may have
broken stop tabs and/or a missing front cap.
13. Verify proper operation of the A/C system.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Refrigerant Filter: > 03-01-38-019A > Sep > 04 > A/C - Underhood Rattle
Noise on Hard Acceleration
Refrigerant Filter: All Technical Service Bulletins A/C - Underhood Rattle Noise on Hard
Acceleration
File In Section: 01 - HVAC
Bulletin No.: 03-01-38~019A
Date: September, 2004
TECHNICAL
Subject: Underhood Rattle Noise Heard On Acceleration (Check A/C System Performance and
Compressor Operation)
Models: 2003-2004 Cadillac CTS 2002-2004 Cadillac Escalade, Escalade EXT 2003-2004 Cadillac
Escalade ESV 2002-2004 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe 2002-2004
GMC Denali, Denali XL, Savana, Sierra, Yukon, Yukon XL 2002-2004 Commercial Upfitter Chassis
Vehicles
with Air Conditioning (A/C)
This bulletin is being revised to update the service procedure and parts information. Please discard
Corporate Bulletin Number 03-01-38-019 (Section 01 - HVAC).
Condition
Some customers may comment about an underhood rattle noise heard on acceleration or a sudden
loss of A/C system performance.
Cause
This condition may be caused by liquid slugging of the A/C compressor. This condition may cause
an internal failure in the A/C compressor. The serpentine belt tensioner and serpentine belt may
also be damaged.
Correction
Technicians are to check the A/C system performance and compressor operation using the
following repair procedure:
1. Open the hood and inspect the A/C compressor for damage and to see if the compressor is
seized. Verify that the serpentine belt is not damaged or missing. If the A/C compressor is seized,
proceed to Step 5.
2. Perform the A/C System Performance test. Refer to the Heating, Ventilation and Air Conditioning
(HVAC) section of SI. Correct any performance concerns or refrigerant leaks that are found.
3. Inspect the vehicle for other possible sources of A/C compressor noise or performance
concerns. Refer to Corporate Bulletin Number 01-01-38-013 for more information.
4. After all other possible sources of A/C compressor noise or performance concerns have been
eliminated, only then should the A/C compressor be replaced.
5. Remove the A/C compressor. Refer to the A/C Compressor Replacement procedure in the
HVAC section of SI.
6. Inspect the transmission cooler lines for damage due to contact from the serpentine belt.
Replace the transmission cooler lines if necessary.
7. Install an inline A/C system filter. Refer to Corporate Bulletin Number 01-01-38-006C for more
information about A/C system flushing and filter installation procedures. An A/C system flush is not
to be done unless prior authorization is given by the GM Area Service Manager (in Canada, the
District Service Manager).
8. Install an A/C Suction Screen. Refer to Corporate Bulletin Number 01-01-39-003A for more
information about A/C suction screen repair recommendations and procedures.
9. Install a new A/C compressor. Refer to the Compressor Replacement procedure in the HVAC
section of SI.
10. Install a new orifice tube for the front A/C system. Refer to the Expansion (Orifice) Tube
Replacement procedure in SI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Refrigerant Filter: > 03-01-38-019A > Sep > 04 > A/C - Underhood Rattle
Noise on Hard Acceleration > Page 2867
11. If the vehicle is a 2003 model year Chevrolet Express or GMC Savana van, the vehicle may
require a new accumulator. Refer to Corporate Bulletin Number 03-01-38-016 for more information.
This bulletin refers to an updated design accumulator that may improve the performance of the A/C
system.
12. Install a new serpentine belt tensioner and serpentine belt if they have been damaged due to
A/C system slugging or an A/C compressor seizure. The serpentine belt tensioner may have
broken stop tabs and/or a missing front cap.
13. Verify proper operation of the A/C system.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60)
Refrigerant Filter: Service and Repair A/C Refrigerant Filter Installation (C60)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
IMPORTANT: The A/C Refrigerant filter, AC P/N 15-1696 must be installed to the A/C evaporator
tube between the condenser and evaporator. The installation of this A/C refrigerant filter eliminates
the need for flushing.
1. Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 2. Measure 50 mm (2 in) from the bend on the evaporator tube (2) near the expansion
tube end and mark the location. 3. Measure 50.8 mm (2 in) from the mark on the evaporator tube
(2) from the previous step.
IMPORTANT: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when
removing the burrs.
4. Using a tubing cutter, cut the marked section of the evaporator tube (2). 5. Remove the burrs
from the evaporator tube (2).
6. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1).
IMPORTANT: DO NOT install the O-rings (2) in this step.
7. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves. 8. Install the ferrules
(3) with the small end toward the nut (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2870
9. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
10. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C
refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
11. Remove the nuts (4) from the A/C refrigerant filter (1). 12. Coat the O-rings (2) with 525
viscosity refrigerant oil. 13. Install the O-rings (2) to the evaporator tube halves. 14. Install the nuts
(4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
15. Evacuate and recharge the system. Refer to Refrigerant Recovery and Recharging. 16. Leak
test the fittings of the component using the J 39400-A. 17. Install the air cleaner. Refer to Air
Cleaner Assembly Replacement in Computers and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2871
Refrigerant Filter: Service and Repair A/C Refrigerant Filter Installation (C69)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
IMPORTANT: The A/C refrigerant filter, AC P/N 15-1696 must be installed to the A/C evaporator
tube (liquid line) between the condenser and evaporator. The installation of this A/C refrigerant filter
eliminates the need for flushing.
1. Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 2. Remove the evaporator tube (2) from the vehicle. 3. Measure 45 mm (1.75 in) from the
bend on the condenser end of the evaporator tube (2) and mark the location. 4. Measure 50.8 mm
(2 in) from the mark on the evaporator tube (2) towards the evaporator from the previous step.
IMPORTANT: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when
removing the burrs.
5. Using a tubing cutter, cut the marked section of the evaporator tube (2). 6. Remove the burrs
from the evaporator tube (2).
7. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1).
IMPORTANT: Do Not install the O-rings (2) in this step.
8. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves. 9. Install the ferrules
(3) with the small end toward the nut (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2872
10. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing
towards the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
11. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C
refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
12. Remove the nuts (4) from the A/C refrigerant filter (1). 13. Coat the O-rings (2) with 525
viscosity refrigerant oil. 14. Install the O-rings (2) to the evaporator tube halves. 15. Install the nuts
(4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2873
16. Install the evaporator tube (2) to the vehicle. 17. Evacuate and recharge the system. Refer to
Refrigerant Recovery and Recharging. 18. Leak test the fittings of the component using the J
39400-A. 19. Install the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and
Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2874
Refrigerant Filter: Service and Repair A/C Refrigerant Filter Replacement (C60)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant from the system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems.
IMPORTANT: The nuts (4) and the ferrules (3) will remain on the evaporator tube. Do not try to
remove.
3. Remove the nuts (4) from the A/C refrigerant filter (1).
4. Remove the A/C refrigerant filter (3) from the evaporator tube (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2875
1. Coat the O-rings (2) with 525 viscosity refrigerant oil. 2. Install the O-rings (2) to the evaporator
tube.
3. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2876
4. Install the nuts (4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
5. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging. 6. Leak test the
fitting(s) of the repaired or reinstalled component using the J 39400-A. 7. Install the air cleaner.
Refer to Air Cleaner Assembly Replacement in Computers and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2877
Refrigerant Filter: Service and Repair A/C Refrigerant Filter Replacement (C69)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant from the system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 3. Remove the evaporator tube (2) from the vehicle.
IMPORTANT: The nuts (4) and ferrules (3) will remain on the evaporator tube. Do not try to
remove.
4. Remove the nuts (4) from the A/C refrigerant filter (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2878
5. Remove the A/C refrigerant filter (3) from the evaporator tube (2).
INSTALLATION PROCEDURE
1. Lubricate the O-rings (2) with 525 viscosity refrigerant oil. 2. Install the O-rings (2) to the
evaporator tube.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2879
3. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
4. Install the nuts (4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2880
5. Install the evaporator tube (2) to the vehicle. 6. Recharge the A/C system. Refer to Refrigerant
Recovery and Recharging. 7. Leak test the fitting(s) of the repaired or reinstalled component using
the J39400-A. 8. Install the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers
and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2881
Refrigerant Filter: Service and Repair
A/C Refrigerant Filter Installation (C60)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
IMPORTANT: The A/C Refrigerant filter, AC P/N 15-1696 must be installed to the A/C evaporator
tube between the condenser and evaporator. The installation of this A/C refrigerant filter eliminates
the need for flushing.
1. Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 2. Measure 50 mm (2 in) from the bend on the evaporator tube (2) near the expansion
tube end and mark the location. 3. Measure 50.8 mm (2 in) from the mark on the evaporator tube
(2) from the previous step.
IMPORTANT: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when
removing the burrs.
4. Using a tubing cutter, cut the marked section of the evaporator tube (2). 5. Remove the burrs
from the evaporator tube (2).
6. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1).
IMPORTANT: DO NOT install the O-rings (2) in this step.
7. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves. 8. Install the ferrules
(3) with the small end toward the nut (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2882
9. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
10. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C
refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
11. Remove the nuts (4) from the A/C refrigerant filter (1). 12. Coat the O-rings (2) with 525
viscosity refrigerant oil. 13. Install the O-rings (2) to the evaporator tube halves. 14. Install the nuts
(4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
15. Evacuate and recharge the system. Refer to Refrigerant Recovery and Recharging. 16. Leak
test the fittings of the component using the J 39400-A. 17. Install the air cleaner. Refer to Air
Cleaner Assembly Replacement in Computers and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
A/C Refrigerant Filter Installation (C69)
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2883
J 39400-A Halogen Leak Detector
IMPORTANT: The A/C refrigerant filter, AC P/N 15-1696 must be installed to the A/C evaporator
tube (liquid line) between the condenser and evaporator. The installation of this A/C refrigerant filter
eliminates the need for flushing.
1. Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 2. Remove the evaporator tube (2) from the vehicle. 3. Measure 45 mm (1.75 in) from the
bend on the condenser end of the evaporator tube (2) and mark the location. 4. Measure 50.8 mm
(2 in) from the mark on the evaporator tube (2) towards the evaporator from the previous step.
IMPORTANT: Do not allow metal burrs to enter the evaporator tube (2) during cutting or when
removing the burrs.
5. Using a tubing cutter, cut the marked section of the evaporator tube (2). 6. Remove the burrs
from the evaporator tube (2).
7. Remove the nuts (4), the ferrules (3), and the O-rings (2) from the A/C refrigerant filter (1).
IMPORTANT: Do Not install the O-rings (2) in this step.
8. Push the nuts (4) and ferrules (3) over each of the evaporator tube halves. 9. Install the ferrules
(3) with the small end toward the nut (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2884
10. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing
towards the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
11. While holding the evaporator tube in the A/C refrigerant filter (1), tighten the nuts (4) to the A/C
refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
12. Remove the nuts (4) from the A/C refrigerant filter (1). 13. Coat the O-rings (2) with 525
viscosity refrigerant oil. 14. Install the O-rings (2) to the evaporator tube halves. 15. Install the nuts
(4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2885
16. Install the evaporator tube (2) to the vehicle. 17. Evacuate and recharge the system. Refer to
Refrigerant Recovery and Recharging. 18. Leak test the fittings of the component using the J
39400-A. 19. Install the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and
Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
A/C Refrigerant Filter Replacement (C60)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant from the system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems.
IMPORTANT: The nuts (4) and the ferrules (3) will remain on the evaporator tube. Do not try to
remove.
3. Remove the nuts (4) from the A/C refrigerant filter (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2886
4. Remove the A/C refrigerant filter (3) from the evaporator tube (2).
INSTALLATION PROCEDURE
1. Coat the O-rings (2) with 525 viscosity refrigerant oil. 2. Install the O-rings (2) to the evaporator
tube.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2887
3. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
4. Install the nuts (4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
5. Recharge the A/C system. Refer to Refrigerant Recovery and Recharging. 6. Leak test the
fitting(s) of the repaired or reinstalled component using the J 39400-A. 7. Install the air cleaner.
Refer to Air Cleaner Assembly Replacement in Computers and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
A/C Refrigerant Filter Replacement (C69)
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant from the system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers and Controls
Systems. 3. Remove the evaporator tube (2) from the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2888
IMPORTANT: The nuts (4) and ferrules (3) will remain on the evaporator tube. Do not try to
remove.
4. Remove the nuts (4) from the A/C refrigerant filter (1).
5. Remove the A/C refrigerant filter (3) from the evaporator tube (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2889
1. Lubricate the O-rings (2) with 525 viscosity refrigerant oil. 2. Install the O-rings (2) to the
evaporator tube.
3. Install the A/C refrigerant filter (3) to the evaporator tube (2) with the flow arrow pointing towards
the evaporator.
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2890
4. Install the nuts (4) to the A/C refrigerant filter (1).
Tighten Tighten the nuts to 15 N.m (11 lb ft).
5. Install the evaporator tube (2) to the vehicle. 6. Recharge the A/C system. Refer to Refrigerant
Recovery and Recharging. 7. Leak test the fitting(s) of the repaired or reinstalled component using
the J39400-A. 8. Install the air cleaner. Refer to Air Cleaner Assembly Replacement in Computers
and Controls Systems.
"For a description of the RPO Code(s) shown in this article or any of the images therein, refer to
the RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Suction Screen Installation
TOOL REQUIRED
J 44551 Suction Screen Kit
IMPORTANT: Suction screens are intended to be installed in the suction hose after a major
compressor failure.
The suction screens are available in 3 different sizes.
1. Insert the J 44551-6 sizing tool into the suction hose to select the correct size suction screen. 2.
Insert the suction screen into the compressor end of the suction hose. 3. Install the correct mandrel
to the J 44551-5. 4. Install the J 44551-5 screen installation tool over the end of the suction hose
and the suction screen.
IMPORTANT: Correct placement of the J 44551-5 is critical.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Filters > Refrigerant Filter > Component Information > Service and Repair >
A/C Refrigerant Filter Installation (C60) > Page 2891
5. Tighten the forcing screw of the J 44551-5. The suction screen is fully installed when the screen
is flush with the end of the suction hose fitting. 6. Remove the J 44551-5 suction screen tool from
the suction hose.
IMPORTANT: After a major compressor failure an A/C refrigerant filter should also be installed.
7. Install an A/C refrigerant filter. 8. Install the J 44551-1 Suction Screen Notification label.
Suction Screen Replacement
TOOLS REQUIRED
- J 42220 Universal Leak Detection Lamp
- J 44551 Suction Screen Kit
REMOVAL PROCEDURE
1. Recover the refrigerant from the A/C system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the A/C compressor hose assembly bolt. 3. Separate the A/C compressor hose assembly
from the A/C compressor.
IMPORTANT: The suction screens are available in 3 different sizes.
4. Select the proper size removal tool from the J 44551. 5. Remove the suction screen using the J
44551-31 suction screen removal tool.
- Thread the forcing screw into the suction screen.
- Tighten the nut on the forcing screw to remove the suction screen.
INSTALLATION PROCEDURE
1. Insert the J 44551-6 sizing tool into the suction hose to select the correct size suction screen. 2.
Insert the suction screen into the suction hose. 3. Install the J 44551-3 mandrel to the J 44551-5. 4.
Install the J 44551-5 suction screen installation tool over the end of the suction hose and the
suction screen.
IMPORTANT: Correct placement of the J 44551-5 is critical.
5. Tighten the forcing screw of the J 44551-5.
The suction screen is fully installed when the screen is flush with the end of the suction hose.
6. Remove the J 44551-5 suction screen tool from the suction hose. 7. Replace the seal washers.
Refer to Compressor Sealing Washers Replacement. 8. Install the A/C compressor hose assembly
to the A/C compressor.
NOTE: Refer to Fastener Notice in Service Precautions.
9. Install the A/C compressor hose assembly bolt.
Tighten Tighten the bolt to 34 N.m (25 lb ft).
10. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging. 11.
Leak test the fittings of the component using the J 42220.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement
Coolant Line/Hose: Service and Repair Radiator Vent Inlet Hose Replacement
Radiator Vent Inlet Hose Replacement
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Reposition the vent
inlet hose clamp from the radiator. 3. Remove the vent inlet hose from the radiator. 4. Reposition
the vent inlet hose clamp from the surge tank. 5. Remove the vent inlet hose from the surge tank.
Installation Procedure
1. Install the vent inlet hose to the surge tank. 2. Reposition the vent inlet hose clamp to the surge
tank. 3. Install the vent inlet hose to the radiator. 4. Reposition the vent inlet hose clamp to the
radiator. 5. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2897
Coolant Line/Hose: Service and Repair Surge Tank Hose/Pipe Replacement - Inlet
Surge Tank Hose/Pipe Replacement - Inlet
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Reposition the surge
tank inlet hose clamp from the radiator. 3. Remove the surge tank inlet hose from the radiator.
4. Reposition the surge tank inlet hose clamp at the surge tank. 5. Remove the surge tank inlet
hose (1) from the surge tank.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2898
1. Install the surge tank inlet hose (1) to the surge tank. 2. Position the surge tank inlet hose clamp
to the surge tank.
3. Install the surge tank inlet hose to the radiator. 4. Position the surge tank inlet hose clamp to the
radiator. 5. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2899
Coolant Line/Hose: Service and Repair Surge Tank Hose/Pipe Replacement - Outlet
Surge Tank Hose/Pipe Replacement - Outlet (4.8L, 5.31-, and 6.0L Engines)
- Tools Required J 43181 Heater Line Quick Connect Release Tool
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct.
4. If equipped without regular production option (RPO) C36 auxiliary heater, remove the surge
tank/heater outlet hose (1) from the mounting clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2900
5. If equipped with RPO C36 auxiliary heater, remove the surge tank theater outlet hose (1) from
the mounting clip.
6. Install the J 43181 to the surge tank outlet hose. 7. Close the J 43181 around the surge tank
outlet hose. 8. Firmly pull the J 43181 into the quick connect end of the outlet hose.
9. If equipped without RPO C36 auxiliary heater, firmly grasp the outlet hose. Pull the outlet hose in
order to disengage the hose from the heater and
blower module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2901
10. If equipped with RPO C36 auxiliary heater, firmly grasp the outlet hose. Pull the outlet hose in
order to disengage the hose from the heater and
blower module.
11. Reposition the surge tank outlet hose clamp at the surge tank. 12. Remove the surge tank
outlet hose (2) from the surge tank.
13. Reposition the surge tank outlet hose clamp at the water pump. 14. Remove the surge tank
outlet hose from the water pump. 15. Remove the surge tank outlet hose.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2902
1. Install the surge tank outlet hose. 2. Install the surge tank outlet hose to the water pump. 3.
Position the surge tank outlet hose clamp to the water pump.
4. Install the surge tank outlet hose (2) to the surge tank. 5. Position the surge tank outlet hose
clamp to the surge tank.
6. If equipped with RPO C36 auxiliary heater, connect the surge tank outlet hose to the heater and
blower module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2903
7. If equipped without RPO C36 auxiliary heater, connect the surge tank outlet hose to the heater
and blower module.
Firmly push the hose onto the heater and blower module pipe until an audible click is heard.
8. If equipped with RPO C36 auxiliary heater, install the surge tank/heater outlet hose (1) to the
mounting clip.
9. If equipped without RPO C36 auxiliary heater, install the surge tank/heater outlet hose (1) to the
mounting clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Coolant Line/Hose > Component Information > Service and Repair
> Radiator Vent Inlet Hose Replacement > Page 2904
10. Install the air cleaner outlet duct.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
11. Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
12. Fill the cooling system, Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary
Heater Hose: Service and Repair Heater Pipe Replacement - Auxiliary
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the auxiliary heater pipes (1, 2) from the heater inlet and outlet tees (3, 4). 3. Loosen the
right front wheelhouse to gain access to the clamp behind the wheelhouse. Refer to Wheelhouse
Panel Replacement in Body Front
End.
4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
5. Remove the auxiliary heater pipes (2, 3) from the auxiliary heater core.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2909
6. Remove the heater/A/C tubes retaining nut (4) from the stud (1) at the frame (6). 7. Remove the
auxiliary heater pipes (2) from the clamps (5). 8. Remove the auxiliary heater pipes from the
vehicle.
INSTALLATION PROCEDURE
1. Install the auxiliary healer pipes to the vehicle. 2. Install the auxiliary heater pipes (2) to the
clamps (5).
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the heater/A/C tubes retaining nut (4)10 the stud (1) at the frame (6).
Tighten Tighten the heater/A/C tubes retaining nut to 7 N.m (62 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2910
4. Install the auxiliary heater pipes (2, 3) to the auxiliary heater core. 5. Lower the vehicle. Refer to
Lifting and Jacking the Vehicle. 6. Install the right front wheelhouse.
7. Install the auxiliary heater pipes (1, 2)10 the heater inlet and outlet tees (3, 4). 8. Fill the cooling
system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2911
Heater Hose: Service and Repair Heater Hose Replacement - Inlet
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the air intake tube. 3. Remove the heater and surge tank hoses from the mounting clip. 4.
Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2912
6. Remove the inlet heater hose from the water pump.
7. Remove the inlet heater hose.
INSTALLATION PROCEDURE
1. Install the inlet heater hose.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2913
2. Install the inlet heater hose to the water pump.
3. Connect the heater hose to the heater core. Firmly push the quick connect onto the heater core
pipe until you hear an audible click. 4. Install the heater and surge tank hoses to the mounting clip.
5. Install the air intake tube. 6. Fill the cooling system. Refer to Draining and Filling Cooling System
in Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2914
Heater Hose: Service and Repair Heater Hose Replacement - Outlet
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the air intake tube. 3. Remove the heater and surge tank hoses from the mounting clip. 4.
Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2915
6. Remove the outlet heater hose from the water pump. 7. Reposition the outlet heater hose clamp
at the surge tank. 8. Remove the outlet heater hose from the surge tank.
9. Remove the outlet heater hose.
INSTALLATION PROCEDURE
1. Install the outlet heater hose.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2916
2. Install the outlet heater hose to the water pump. 3. Install the outlet heater hose to the surge
tank. 4. Install the outlet heater hose clamp to the surge tank.
5. Connect the heater and surge tank hoses to the heater core.
Firmly push the quick connect onto the heater core hose until you hear an audible click.
6. Install the heater and surge tank hoses to the mounting clip. 7. Install the air intake tube. 8. Fill
the cooling system. Refer to Draining and Filling Cooling System in Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2917
Heater Hose: Service and Repair Heater and A/C Pipe Repair - Auxiliary
TOOLS REQUIRED
J 41425 A/C Line Repair Kit
Do not service the rear A/C or heater lines as a complete unit. Service the rear A/C or heater lines
as a sectional repair.
You can obtain the various sections of line through GMSPO.
Use the J 41425 when any of the following actions damage the rear A/C or heater lines:
- Rub-through
- Collision damage
- Leakage in the system
Minimum Tube Length Required Table
IMPORTANT: When you section the rear A/C or heater lines, ensure that the correct minimum
length remains in the straight part of the line on both sides of the splice.
Follow the Straight Line Repair procedure in order to repair line damage in a straight section of line.
Follow the Line Sectioning Repair procedure in order to repair any damage in a bend area. Do not
repair the rear A/C or heater lines in a bend area, replace the lines. Maintaining the original line
shape will prevent vibrations and rub-through.
Straight Line Repair 1. Recover the refrigerant, if repairing the A/C lines. Refer to Refrigerant
Recovery and Recharging. 2. Drain the coolant, if repairing the heater lines. Refer to Draining and
Filling Cooling System in Engine Cooling. 3. Raise and support the vehicle. Refer to Lifting and
Jacking the Vehicle. 4. Locate the area that requires repair. 5. Obtain a length of replacement line
to make the repair. 6. Use a tubing cutter in order to cut and remove the section of damaged line.
IMPORTANT: The length of the replacement line must be the same as the section being replaced.
7. Use a tubing cutter in order to cut the replacement line to length. 8. Use the cleaning pad from
the J41425 in order to clean any burrs or grease from the line ends. Be sure to clean at least 19
mm (0.75 in) from the
line ends.
9. Use the LOK prep sealant in order to prep the line ends.
10. Apply one drop of the J 41425-3 sealing compound to the outside of each end of the line. 11.
Insert the line ends into the LOK fitting. 12. Rotate the LOK fitting one complete turn in order to
evenly distribute the sealing compound around the lines. 13. Install the correct LOK fitting jaws into
the J 41425-1 tool. 14. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK
connector ends are positioned in the counter bores of the jaws.
IMPORTANT: Hold the J 41425-1 tool body with a 3/8" breaker bar.
15. Tighten the forcing screw of the J 41425-1 tool.
When fully seated, the LOK connector collars will bottom out on the center shoulder of the LOK
fitting.
16. Loosen the forcing screw and remove the J 41425-1 tool from the repaired line. 17. Repeat
Step 8 through Step 16 to repair the other end of the line. 18. Verify that the LOK fittings are
correctly installed. 19. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Heater Hose > Component Information > Service and Repair >
Heater Pipe Replacement - Auxiliary > Page 2918
20. Refill the coolant, if drained. Refer to Draining and Filling Cooling System in Engine Cooling.
21. Evacuate and recharge the refrigerant, if repairing the A/C lines. Refer to Refrigerant Recovery
and Recharging.
Line Sectioning Repair 1. Recover the refrigerant, if repairing the A/C lines. Refer to Refrigerant
Recovery and Recharging. 2. Drain the coolant, if repairing the heater lines. Refer to Draining and
Filling Cooling System in Engine Cooling. 3. Raise and support the vehicle. Refer to Lifting and
Jacking the Vehicle. 4. Obtain a new A/C or heater line for sectioning.
IMPORTANT: Stagger the splices if repairing more than one line.
5. Scribe a mark on the line that will be sectioned. 6. Use a tubing cutter in order to cut the line or
lines being replaced. 7. Remove the section of line being replaced from the vehicle.
IMPORTANT: The length of the replacement line must be the same as the line being replaced.
8. Install the replacement line to the vehicle. 9. Use a tubing cutter in order to cut the replacement
line to length.
10. Use the cleaning pad from the J 41425 in order to clean any burrs or grease. Be sure to clean
at least 19 mm (0.75 in) from the A/C line. 11. Use the LOK prep sealant in order to prep the A/C or
heater line. 12. Apply one drop of the J 41425-3 sealing compound to the outside of each line end.
13. Insert the line ends into the LOK fitting. 14. Rotate the LOK fitting one complete turn in order to
evenly distribute the sealing compound around the lines. 15. Install the correct LOK fitting jaws into
the J41425-1 tool. 16. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK
connector ends are positioned in the counter bores of the jaws. 17. Hold the tool body with a 3/8"
breaker bar. Turn the forcing screw until both of the connector collars bottom on the center
shoulder of the LOK
fitting.
18. Loosen the forcing screw. Remove the tool from the repaired line. 19. Verify that the LOK fitting
is correctly installed. 20. Lower the vehicle. 21. Refill the coolant, if drained. Refer to Draining and
Filling Cooling System in Engine Cooling. 22. Evacuate and recharge the refrigerant, if repairing
the A/C lines. Refer to Refrigerant Recovery and Recharging.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > Customer Interest for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride Control
Message/DTC C0580
Hose/Line HVAC: Customer Interest Suspension - Service Ride Control Message/DTC C0580
Bulletin No.: 03-03-11-001
Date: July 22, 2003
TECHNICAL
Subject: Service Ride Control Message Displayed, DTC C0580 Set (Replace Right Front Shock
Absorber Solenoid Connector and Install New A/C Suction Hose and Auxiliary A/C Evaporator
Hose)
Models: 2002-2003 Cadillac Escalade 2003 Cadillac Escalade ESV 2001-2003 Chevrolet
Suburban, Tahoe 2001-2003 GMC Yukon, Yukon XL with Rear Air Conditioning System (RPO
C69) and Real Time Damping Chassis Package (RPO Z55)
Condition
Some customers may comment on the Service Ride Control message being displayed. Upon
investigation, the technician may find DTC C0580 set.
Cause
Poor clearance between the auxiliary A/C evaporator hose and the right front shock absorber
damper solenoid connector may be the cause of this condition. Contact may occur damaging the
connector and causing a poor connection at the damper solenoid.
Correction
Replace the right front shock absorber solenoid connector and install a new A/C suction hose and
auxiliary A/C evaporator hose. These new A/C hoses will provide proper routing to prevent contact
between the auxiliary A/C evaporator hose and the right front shock absorber damper solenoid
connector. Use the procedure listed below.
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging in the HVAC sub-section
of the Service Manual.
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in the General Information sub-section
of the Service Manual.
3. Remove the right front wheel assembly.
4. Remove the right front wheelhouse panel.
5. Remove the nut and the auxiliary evaporator hose from the accumulator line block.
6. Remove the nut and the suction hose from the accumulator.
7. Remove the bolt and the suction hose from the compressor.
8. Install the new suction hose and bolt to the compressor.
Tighten
Tighten the bolt to 16 N.m (12 lb ft).
9. Install the new suction hose and nut to the accumulator.
Tighten
Tighten the nut to 16 N.m (12 lb ft).
10. Release 4 line retaining clamps, starting at the wheelhouse and along the underbody towards
the rear of vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > Customer Interest for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride Control
Message/DTC C0580 > Page 2927
11. From under the vehicle, mark the location on the auxiliary evaporator line where the line will be
cut. Using the forward running board bracket as a reference, mark the location inline with the
bracket-to-body bolt (1). If the vehicle is not equipped with running boards, mark the location inline
with the bolt hole.
12. Using a tubing cutter, cut the marked section of the auxiliary evaporator line.
13. Remove the front section of the auxiliary evaporator hose from the vehicle and discard.
14. Install the new front section of the auxiliary evaporator hose into the vehicle.
15. On both sections of the auxiliary evaporator line, cut back the plastic coating approximately 76
mm (3 in).
16. Splice in the new front section of the auxiliary evaporator hose using J 41425 A/C Line Repair
Kit and J 41425-750 splice. Refer to the Heater and A/C Pipe Repair-Auxiliary procedure in the
Service Manual.
17. Install the auxiliary evaporator hose to the accumulator line block and nut.
Tighten
Tighten the nut to 16 N.m (12 lb ft).
18. Secure the line retaining clamps.
19. Install the wheelhouse panel.
20. Install the wheel assembly.
21. Lower the vehicle.
22. Inject the oil into the A/C system that was removed during the recovery process using J 45037
A/C Oil Injection Kit.
23. Evacuate and recharge the refrigerant. Refer to Refrigerant Recovery and Recharging in the
HVAC sub-section of the Service Manual.
24. Leak test the fitting and splice using J 39400-A Halogen Leak Detector.
25. Replace the right front shock absorber solenoid connector using service connector, P/N
88986417. Refer to Wiring Repairs in the Wiring Systems sub-section of the Service Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > Customer Interest for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride Control
Message/DTC C0580 > Page 2928
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride
Control Message/DTC C0580
Hose/Line HVAC: All Technical Service Bulletins Suspension - Service Ride Control Message/DTC
C0580
Bulletin No.: 03-03-11-001
Date: July 22, 2003
TECHNICAL
Subject: Service Ride Control Message Displayed, DTC C0580 Set (Replace Right Front Shock
Absorber Solenoid Connector and Install New A/C Suction Hose and Auxiliary A/C Evaporator
Hose)
Models: 2002-2003 Cadillac Escalade 2003 Cadillac Escalade ESV 2001-2003 Chevrolet
Suburban, Tahoe 2001-2003 GMC Yukon, Yukon XL with Rear Air Conditioning System (RPO
C69) and Real Time Damping Chassis Package (RPO Z55)
Condition
Some customers may comment on the Service Ride Control message being displayed. Upon
investigation, the technician may find DTC C0580 set.
Cause
Poor clearance between the auxiliary A/C evaporator hose and the right front shock absorber
damper solenoid connector may be the cause of this condition. Contact may occur damaging the
connector and causing a poor connection at the damper solenoid.
Correction
Replace the right front shock absorber solenoid connector and install a new A/C suction hose and
auxiliary A/C evaporator hose. These new A/C hoses will provide proper routing to prevent contact
between the auxiliary A/C evaporator hose and the right front shock absorber damper solenoid
connector. Use the procedure listed below.
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging in the HVAC sub-section
of the Service Manual.
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in the General Information sub-section
of the Service Manual.
3. Remove the right front wheel assembly.
4. Remove the right front wheelhouse panel.
5. Remove the nut and the auxiliary evaporator hose from the accumulator line block.
6. Remove the nut and the suction hose from the accumulator.
7. Remove the bolt and the suction hose from the compressor.
8. Install the new suction hose and bolt to the compressor.
Tighten
Tighten the bolt to 16 N.m (12 lb ft).
9. Install the new suction hose and nut to the accumulator.
Tighten
Tighten the nut to 16 N.m (12 lb ft).
10. Release 4 line retaining clamps, starting at the wheelhouse and along the underbody towards
the rear of vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride
Control Message/DTC C0580 > Page 2934
11. From under the vehicle, mark the location on the auxiliary evaporator line where the line will be
cut. Using the forward running board bracket as a reference, mark the location inline with the
bracket-to-body bolt (1). If the vehicle is not equipped with running boards, mark the location inline
with the bolt hole.
12. Using a tubing cutter, cut the marked section of the auxiliary evaporator line.
13. Remove the front section of the auxiliary evaporator hose from the vehicle and discard.
14. Install the new front section of the auxiliary evaporator hose into the vehicle.
15. On both sections of the auxiliary evaporator line, cut back the plastic coating approximately 76
mm (3 in).
16. Splice in the new front section of the auxiliary evaporator hose using J 41425 A/C Line Repair
Kit and J 41425-750 splice. Refer to the Heater and A/C Pipe Repair-Auxiliary procedure in the
Service Manual.
17. Install the auxiliary evaporator hose to the accumulator line block and nut.
Tighten
Tighten the nut to 16 N.m (12 lb ft).
18. Secure the line retaining clamps.
19. Install the wheelhouse panel.
20. Install the wheel assembly.
21. Lower the vehicle.
22. Inject the oil into the A/C system that was removed during the recovery process using J 45037
A/C Oil Injection Kit.
23. Evacuate and recharge the refrigerant. Refer to Refrigerant Recovery and Recharging in the
HVAC sub-section of the Service Manual.
24. Leak test the fitting and splice using J 39400-A Halogen Leak Detector.
25. Replace the right front shock absorber solenoid connector using service connector, P/N
88986417. Refer to Wiring Repairs in the Wiring Systems sub-section of the Service Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Hose/Line HVAC: > 03-03-11-001 > Jul > 03 > Suspension - Service Ride
Control Message/DTC C0580 > Page 2935
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Technical Service
Bulletins > Page 2936
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement
Hose/Line HVAC: Service and Repair Evaporator Tube Replacement
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging. 2. Remove the
evaporator tube nut from the evaporator. 3. Disconnect the evaporator tube from the evaporator. 4.
Remove the evaporator tube nut from the auxiliary A/C tube (if equipped). 5. Disconnect the
evaporator tube from the auxiliary A/C tube (if equipped).
6. Remove the right park/turn signal lamp. 7. Remove the grille from the vehicle. 8. Remove the
evaporator tube nut from the condenser. 9. Disconnect the evaporator tube from the condenser.
10. Remove the evaporator tube from the vehicle. 11. Discard all of the used sealing washers. Cap
all of the open connections.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2939
1. Connect the evaporator tube to the condenser using new sealing washers.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the evaporator tube nut to the condenser.
Tighten Tighten the nut to 16 N.m (12 lb ft).
3. Install the grille to the vehicle. 4. Install the right park/turn signal lamp. 5. Connect the evaporator
tube to the auxiliary A/C tube using new sealing washers (if equipped). 6. Install the evaporator
tube nut to the auxiliary A/C tube (if equipped).
Tighten Tighten the nut to 16 N.m (12 lb ft).
7. Connect the evaporator tube to the evaporator. 8. Install the evaporator tube nut to the
evaporator.
Tighten Tighten the nut to 16 N.m (12 lb ft).
9. Evacuate and recharge the system. Refer to Refrigerant Recovery and Recharging.
10. Leak test the fittings of the components using the J 39400-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2940
Hose/Line HVAC: Service and Repair A/C Suction Hose/Line
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging. 2. Remove the suction
hose mounting bolt from the A/C compressor. 3. Remove the suction hose (2) from the A/C
compressor.
4. Remove the suction hose nut from the accumulator. 5. Remove the suction hose from the
accumulator. 6. Remove the suction hose assembly from the vehicle. 7. Discard all of the used
sealing washers. Cap the system openings.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2941
1. Install the suction hose to the vehicle. 2. Install the suction hose to the accumulator.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the suction hose nut to the accumulator.
Tighten Tighten the nut to 16 N.m (12 lb ft).
4. Install the suction hose (2) to the compressor using new sealing washers. 5. Install the suction
hose mounting bolt to the A/C compressor.
Tighten Tighten the bolt to 16 N.m (12 lb ft).
6. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging. 7. Leak
test the fittings of the component using the J 39400-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2942
Hose/Line HVAC: Service and Repair A/C Discharge Hose/Line
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging. 2. Remove the
discharge hose mounting bolt (2) from the A/C compressor. 3. Remove the discharge hose (1) from
the A/C compressor. 4. Remove the upper radiator baffle.
5. Remove the discharge hose nut from the condenser. 6. Remove the discharge hose from the
condenser. 7. Disconnect the electrical connector from the A/C recirculation switch. 8. Remove the
discharge hose from the vehicle. 9. Discard all of the used sealing washers. Cap the system
openings.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2943
1. Install the discharge hose (1) to the vehicle. 2. Connect the electrical connector to the A/C
recirculation switch.
3. Install the discharge hose to the condenser using new sealing washers.
NOTE: Refer to Fastener Notice in Service Precautions.
4. Install the discharge hose nut to the condenser.
Tighten Tighten the nut to 16 N.m (12 lb ft).
5. Install the upper air baffle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2944
6. Install the discharge hose (1) to the A/C compressor using new sealing washers. 7. Install the
discharge hose mounting bolt.
Tighten Tighten the bolt to 16 N.m (12 lb ft).
8. Evacuate and recharge the A/C system. Refer to Refrigerant Recovery and Recharging. 9. Leak
test the fittings of the component using the J 39400-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2945
Hose/Line HVAC: Service and Repair Evaporator Tube Replacement - Auxiliary
TOOLS REQUIRED
J 39400-A Halogen Leak Detector
REMOVAL PROCEDURE
1. Recover the refrigerant from the system. Refer to Refrigerant Recovery and Recharging. 2.
Remove the auxiliary A/C evaporator tubes (3) from the condenser tube (2) and the accumulator
(5). 3. Loosen the right front wheelhouse to gain access to the clamp behind the wheelhouse. Refer
to Wheelhouse Panel Replacement in Body Front
End.
4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
5. Remove the retaining nut (2) and the auxiliary A/C evaporator tubes (3) from the auxiliary HVAC
module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2946
6. Remove the heater/A/C tubes retaining nut (4) from the stud (1) at the frame (6). 7. Remove the
auxiliary A/C evaporator tubes (3) from the clamps (5). 8. Remove the auxiliary A/C evaporator
tubes from the vehicle.
INSTALLATION PROCEDURE
1. Install the auxiliary A/C evaporator tubes to the vehicle. 2. Install the auxiliary A/C evaporator
tubes (3) to the clamps (5).
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the heater/A/C tubes retaining nut (4) to the stud (1) at the frame (6).
Tighten Tighten the heater/A/C tubes retaining nut to 7 N.m (62 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Hose/Line HVAC > Component Information > Service and Repair >
Evaporator Tube Replacement > Page 2947
4. Install the auxiliary A/C evaporator tubes (2, 3) and the retaining nut to the auxiliary HVAC
module.
Tighten Tighten the nut to 16 N.m (12 lb ft).
5. Lower the vehicle. Refer to Lifting and Jacking the Vehicle. 6. Install the right front wheelhouse.
Refer to Wheelhouse Panel Replacement in Body Front End.
7. Install the auxiliary A/C evaporator tubes (3) to the condenser tube (2) and the accumulator (5).
Tighten Tighten the nuts to 16 N.m (12 lb ft).
8. Recharge the refrigerant to the system. Refer to Refrigerant Recovery and Recharging. 9. Leak
test the fittings of the component using the J 39400-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information >
Specifications
Power Steering Line/Hose: Specifications
Pressure Hose Connection (At Gear)
........................................................................................................................................................ 33
Nm (24 ft. lbs.) Pressure Hose Connection (At Pump)
...................................................................................................................................................... 28
Nm (20 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information > Service and
Repair > Power Brake Booster Inlet Hose Replacement
Power Steering Line/Hose: Service and Repair Power Brake Booster Inlet Hose Replacement
Power Brake Booster Inlet Hose Replacement
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the brake booster inlet hose (1) from the brake booster (2). 3. Remove the brake
booster inlet hose from the power steering pump. 4. Remove the brake booster inlet hose from the
vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the brake booster inlet hose (1) to the brake booster (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the brake booster inlet hose to the power steering pump.
Tighten the brake booster inlet hose fittings to 27 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information > Service and
Repair > Power Brake Booster Inlet Hose Replacement > Page 2953
Power Steering Line/Hose: Service and Repair Power Brake Booster Outlet Hose Replacement
Power Brake Booster Outlet Hose Replacement
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the brake booster outlet hose (1) from the brake booster (2). 3. Remove the clamp
retaining the brake booster outlet hose to the power steering pump. 4. Remove the brake booster
outlet hose from the vehicle.
Installation Procedure
Notice: The inlet and outlet hoses must not be twisted during installation. Do not bend or distort the
inlet or outlet hoses to make installation easier. Failure to follow these procedures could result in
component damage.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the brake booster outlet hose (1) to the brake booster (2).
Position the clamp at the end of the hose.
3. Install the brake booster outlet hose to the power steering pump (4).
Position the clamp at the end of the hose.
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information > Service and
Repair > Power Brake Booster Inlet Hose Replacement > Page 2954
Power Steering Line/Hose: Service and Repair Power Steering Gear Inlet Hose Replacement
With Hydroboost
Power Steering Gear Inlet Hose Replacement (With Hydroboost)
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the power steering gear inlet hose (1) from the brake booster. 3. Remove the power
steering gear inlet hose from the power steering gear. 4. Remove the power steering gear inlet
hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear inlet hose (1) to the brake booster (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear inlet hose to the power steering gear.
Tighten the power steering gear inlet hose fittings to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information > Service and
Repair > Power Brake Booster Inlet Hose Replacement > Page 2955
Without Hydroboost
Power Steering Gear Inlet Hose Replacement (Without Hydroboost)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the engine protection shield.
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
3. Install a drain pan under the vehicle.
4. Remove the power steering gear inlet hose (3) from the power steering pump (1). 5. Remove the
power steering gear inlet hose from the power steering gear. 6. Remove the power steering gear
inlet hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear inlet hose (3) to the power steering pump (1).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear inlet hose to the power steering gear.
Tighten the power steering gear inlet hose fittings to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Install the engine protection shield. 6. Lower
the vehicle. 7. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Power Steering Line/Hose > Component Information > Service and
Repair > Power Brake Booster Inlet Hose Replacement > Page 2956
Power Steering Line/Hose: Service and Repair Power Steering Gear Outlet Hose Replacement
Power Steering Gear Outlet Hose Replacement (Recirculating Ball)
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the power steering gear outlet hose (3) from the steering gear (2). 3. Remove the clamp
retaining the power steering gear outlet hose (3) to the power steering pump (1)
Remove the power steering gear outlet hose from the power steering pump.
4. Remove the power steering gear outlet hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear outlet hose (3) to the power steering pump (1). Position the clamp
at the end of the hose.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear outlet hose to the power steering gear.
Tighten the outlet hose fitting to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet
Radiator Hose: Service and Repair Radiator Hose Replacement - Inlet
Radiator Hose Replacement - Inlet
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct. 4. If necessary, remove the engine sight shield. Refer to
Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (L09) in Engine Mechanical - 4.8L, 5.3L, and 6.OL.
5. Remove the radiator vent inlet hose from the radiator inlet hose clips.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet > Page 2961
6. Reposition the inlet hose clamp from the radiator. 7. Remove the inlet hose from the radiator. 8.
Remove the inlet hose clip from the fan shroud.
9. Reposition the inlet hose clamp from the water outlet.
10. Remove the inlet hose from the water outlet.
Installation Procedure
1. Install the inlet hose to the water outlet. 2. Reposition the inlet hose clamp to the water outlet.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet > Page 2962
3. Install the inlet hose clip to the fan shroud. 4. Install the inlet hose to the radiator. 5. Reposition
the inlet hose clamp to the radiator.
6. Install the radiator vent inlet hose to the radiator inlet hose clips. 7. If necessary, install the
engine sight shield, Refer to Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or
Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.8L, 5.31L, and 6.OL.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
8. Install the air cleaner outlet duct. 9. Tighten the air cleaner outlet duct clamps at the following
locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
10. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet > Page 2963
Radiator Hose: Service and Repair Radiator Hose Replacement - Outlet
Radiator Hose Replacement - Outlet (4.8L, 5.3L, and 6.OL Engines)
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct.
4. Reposition the outlet hose clamp from the water pump. 5. Remove the outlet hose from the
water pump.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet > Page 2964
6. Reposition the outlet hose clamp from the radiator. 7. Remove the outlet hose from the radiator.
Installation Procedure
1. Install the outlet hose to the radiator. 2. Reposition the outlet hose clamp to the radiator.
3. Install the outlet hose to the water pump. 4. Reposition the outlet hose clamp to the water pump.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
5. Install the air cleaner outlet duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Hoses > Radiator Hose > Component Information > Service and Repair >
Radiator Hose Replacement - Inlet > Page 2965
6. Install the radiator inlet hose clip to the outlet duct. 7. Tighten the air cleaner outlet duct clamps
at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
8. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Brake Fluid > Component Information > Specifications
Brake Fluid: Specifications
Hydraulic Brake System Delco Supreme 11 Brake Fluid GM Part No. 12377967 (Canadian P/N
992667) or equivalent DOT-3 brake fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Technical Service Bulletins >
Cooling System - DEX-COOL(R) Coolant Leak Detection Dye
Coolant: Technical Service Bulletins Cooling System - DEX-COOL(R) Coolant Leak Detection Dye
Bulletin No.: 05-06-02-002B
Date: January 18, 2008
INFORMATION
Subject: DEX-COOL(R) Coolant - New Leak Detection Dye J 46366 - Replaces J 29545-6
Models: 1996-2008 GM Passenger Cars and Light/Medium Duty Trucks* (including Saturn)
1997-2008 Isuzu T-Series Medium Duty Tilt Cab Models Built in Janesville and Flint 1999-2008
Isuzu N-Series Medium Duty Commercial Models with 5.7L or 6.0L Gas Engine
2003-2008 HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
*EXCLUDING 2006 and Prior Chevrolet Aveo, Epica, Optra, Vivant and Pontiac Matiz, Wave
Supercede:
This bulletin is being revised to include additional model years. Please discard Corporate Bulletin
Number 05-06-02-002A (Section 06 - Engine/Propulsion System).
Leak detection dye P/N 12378563 (J 29545-6) (in Canada P/N 88900915) may cause
DEX-COOL(R) coolant to appear green in a black vessel making it appear to be conventional
(green) coolant. This may cause a technician to add conventional coolant to a low DEX-COOL(R)
system thus contaminating it. The green DEX-COOL(R) appearance is caused by the color of the
leak detection dye which alters the color of the DEX-COOL(R) coolant.
A new leak detection dye P/N 89022219 (J 46366) (in Canada P/N 89022220) has been released
that does not alter the appearance of the DEX-COOL(R) coolant. When adding the new leak
detection dye the color of the DEX-COOL(R) coolant will not change. For detecting leaks on any
system that uses DEX-COOL(R) leak detection dye P/N 89022219 (in Canada P/N 89022220)
should be used. The new leak detection dye can be used with both conventional and
DEX-COOL(R) coolant.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Technical Service Bulletins >
Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 2974
Coolant: Technical Service Bulletins Cooling System - Coolant Recycling Information
Bulletin No.: 00-06-02-006D
Date: August 15, 2006
INFORMATION
Subject: Engine Coolant Recycling and Warranty Information
Models: 2007 and Prior GM Passenger Cars and Trucks (Including Saturn) 2007 and Prior
HUMMER Vehicles 2005-2007 Saab 9-7X
Attention:
Please address this bulletin to the Warranty Claims Administrator and the Service Manager.
Supercede:
This bulletin is being revised to adjust the title and Include Warranty Information. Please discard
Corporate Bulletin Number 00-06-02-006C (Section 06 - Engine/Propulsion System).
Coolant Reimbursement Policy
General Motors supports the use of recycled engine coolant for warranty repairs/service, providing
a GM approved engine coolant recycling system is used. Recycled coolant will be reimbursed at
the GMSPO dealer price for new coolant plus the appropriate mark-up. When coolant replacement
is required during a warranty repair, it is crucial that only the relative amount of engine coolant
concentrate be charged, not the total diluted volume. In other words: if you are using two gallons of
pre-diluted (50:50) recycled engine coolant to service a vehicle, you may request reimbursement
for one gallon of GM Goodwrench engine coolant concentrate at the dealer price plus the
appropriate warranty parts handling allowance.
Licensed Approved DEX-COOL(R) Providers
Important:
USE OF NON-APPROVED VIRGIN OR RECYCLED DEX-COOL(R) OR DEVIATIONS IN THE
FORM OF ALTERNATE CHEMICALS OR ALTERATION OF EQUIPMENT, WILL VOID THE GM
ENDORSEMENT, MAY DEGRADE COOLANT SYSTEM INTEGRITY AND PLACE THE
COOLING SYSTEM WARRANTY UNDER JEOPARDY.
Shown in Table 1 are the only current licensed and approved providers of DEX-COOL(R). Products
that are advertised as "COMPATIBLE" or "RECOMMENDED" for use with DEX-COOL(R) have not
been tested or approved by General Motors. Non-approved coolants may degrade the
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Technical Service Bulletins >
Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 2975
coolant system integrity and will no longer be considered a 5 yr/150,000 mile (240,000 km) coolant.
Coolant Removal Services/Recycling
The tables include all coolant recycling processes currently approved by GM. Also included is a
primary phone number and demographic information. Used DEX-COOL(R) can be combined with
used conventional coolant (green) for recycling. Depending on the recycling service and/or
equipment, it is then designated as a conventional 2 yr/30,000 mile (50,000 km) coolant or
DEX-COOL(R) 5 yr/150,000 mile (240,000 km) coolant. Recycled coolants as designated in this
bulletin may be used during the vehicle(s) warranty period.
DEX-COOL(R) Recycling
The DEX-COOL(R) recycling service listed in Table 2 has been approved for recycling waste
engine coolants (DEX-COOL) or conventional) to DEX-COOL(R) with 5 yr/150,000 mile (240,000
km) usability. Recycling Fluid Technologies is the only licensed provider of Recycled
DEX-COOL(R) meeting GM6277M specifications and utilizes GM approved inhibitor packages.
This is currently a limited program being monitored by GM Service Operations which will be
expanded as demand increases.
Conventional (Green) Recycling
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Technical Service Bulletins >
Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 2976
Processes shown in the Table 3 are capable of recycling waste engine coolants (DEX-COOL(R) or
conventional) to a conventional (green) coolant. Recycling conventional coolant can be
accomplished at your facility by a technician using approved EQUIPMENT (listed by model number
in Table 3), or by an approved coolant recycling SERVICE which may recycle the coolant at your
facility or at an offsite operation. Refer to the table for GM approved coolant recyclers in either of
these two categories. Should you decide to recycle the coolant yourself, strict adherence to the
operating procedures is imperative. Use ONLY the inhibitor chemicals supplied by the respective
(GM approved) recycling equipment manufacturer.
Sealing Tablets
Cooling System Sealing Tablets (Seal Tabs) should not be used as a regular maintenance item
after servicing an engine cooling system. Discoloration of coolant can occur if too many seal tabs
have been inserted into the cooling system. This can occur if seal tabs are repeatedly used over
the service life of a vehicle. Where appropriate, seal tabs may be used if diagnostics fail to repair a
small leak in the cooling system. When a condition appears in which seal tabs may be
recommended, a specific bulletin will be released describing their proper usage.
Water Quality
The integrity of the coolant is dependent upon the quality of DEX-COOL(R) and water.
DEX-COOL(R) is a product that has enhanced protection capability as well as an extended service
interval. These enhanced properties may be jeopardized by combining DEX-COOL(R) with poor
quality water. If you suspect the water in your area of being poor quality, it is recommended you
use distilled or de-ionized water with DEX-COOL(R).
"Pink" DEX-COOL(R)
DEX-COOL(R) is orange in color to distinguish it from other coolants. Due to inconsistencies in the
mixing of the dyes used with DEX-COOL(R), some batches may appear pink after time. The color
shift from orange to pink does not affect the integrity of the coolant, and still maintains the 5
yr/150,000 mile (240,000 km) service interval.
Back Service
Only use DEX-COOL(R) if the vehicle was originally equipped with DEX-COOL(R).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Technical Service Bulletins >
Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 2977
Contamination
Mixing conventional green coolant with DEX-COOL(R) will degrade the service interval from 5
yrs./150,000 miles (240,000 km) to 2 yrs./30,000 miles (50,000 km) if left in the contaminated
condition. If contamination occurs, the cooling system must be flushed twice immediately and
re-filled with a 50/50 mixture of DEX-COOL(R) and clean water in order to preserve the enhanced
properties and extended service interval of DEX-COOL(R).
After 5 years/150,000 miles (240,000 km)
After 5 yrs/150,000 miles (240,000 km), the coolant should be changed, preferably using a coolant
exchanger. If the vehicle was originally equipped with DEX-COOL(R) and has not had problems
with contamination from non-DEX-COOL(R) coolants, then the service interval remains the same,
and the coolant does not need to be changed for another 5 yrs/150,000 miles (240,000 km)
Equipment (Coolant Exchangers)
The preferred method of performing coolant replacement is to use a coolant exchanger. A coolant
exchanger can replace virtually all of the old coolant with new coolant. Coolant exchangers can be
used to perform coolant replacement without spillage, and facilitate easy waste collection. They
can also be used to lower the coolant level in a vehicle to allow for less messy servicing of cooling
system components. It is recommended that you use a coolant exchanger with a vacuum feature
facilitates removing trapped air from the cooling system. This is a substantial time savings over
repeatedly thermo cycling the vehicle and topping-off the radiator. The vacuum feature also allows
venting of a hot system to relieve system pressure. Approved coolant exchangers are available
through the GMDE (General Motors Dealer Equipment) program.
For refilling a cooling system that has been partially or fully drained for repairs other than coolant
replacement, the Vac-N-Fill Coolant Refill Tool (GE-47716) is recommended to facilitate removal of
trapped air from the cooling system during refill.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Specifications > Capacity
Specifications
Coolant: Capacity Specifications
Add one liter if equipped with rear heating for all engines.
Cooling System Capacity VORTEC 4800 V8 Automatic with Front A/C 14.4 qt (US)
VORTEC 4800 V8 Automatic with Front and Rear A/C 15.8 qt (US)
VORTEC 5300 V8 Automatic with Front A/C 14.4 qt (US)
VORTEC 5300 V8 Automatic with Front and Rear A/C 15.8 qt (US)
Vehicles equipped with optional air conditioner.
VORTEC 6000 V8 Automatic 15.8 qt (US)
VORTEC 6000 V8 Automatic with engine oil cooler 15.4 qt (US)
Vehicles equipped with optional engine cooler
VORTEC 8100 V8 Automatic 20.7 qt (US)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Coolant > Component Information > Specifications > Capacity
Specifications > Page 2980
Coolant: Fluid Type Specifications
Engine Coolant 50/50 mixture of clean, drinkable water and use only GM Goodwrench DEX-COOL
or Havoline DEX-COOL Coolant.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Technical Service Bulletins
> A/T - DEXRON(R)-VI Fluid Information
Fluid - A/T: Technical Service Bulletins A/T - DEXRON(R)-VI Fluid Information
INFORMATION
Bulletin No.: 04-07-30-037E
Date: April 07, 2011
Subject: Release of DEXRON(R)-VI Automatic Transmission Fluid (ATF)
Models:
2008 and Prior GM Passenger Cars and Light Duty Trucks 2003-2008 HUMMER H2 2006-2008
HUMMER H3 2005-2007 Saturn Relay 2005 and Prior Saturn L-Series 2005-2007 Saturn ION
2005-2008 Saturn VUE with 4T45-E 2005-2008 Saab 9-7X Except 2008 and Prior Chevrolet Aveo,
Equinox Except 2006 and Prior Chevrolet Epica Except 2007 and Prior Chevrolet Optra Except
2008 and Prior Pontiac Torrent, Vibe, Wave Except 2003-2005 Saturn ION with CVT or AF23 Only
Except 1991-2002 Saturn S-Series Except 2008 and Prior Saturn VUE with CVT, AF33 or 5AT
(MJ7/MJ8) Transmission Only Except 2008 Saturn Astra
Attention:
DEXRON(R)-VI Automatic Transmission Fluid (ATF) is the only approved fluid for warranty repairs
for General Motors transmissions/transaxles requiring DEXRON(R)-III and/or prior DEXRON(R)
transmission fluids.
Supercede: This bulletin is being revised to update information. Please discard Corporate Bulletin
Number 04-07-30-037D (Section 07 - Transmission/Transaxle).
MANUAL TRANSMISSIONS / TRANSFER CASES and POWER STEERING
The content of this bulletin does not apply to manual transmissions or transfer cases. Any vehicle
that previously required DEXRON(R)-III for a manual transmission or transfer case should now use
P/N 88861800. This fluid is labeled Manual Transmission and Transfer Case Fluid. Some manual
transmissions and transfer cases require a different fluid. Appropriate references should be
checked when servicing any of these components.
Power Steering Systems should now use P/N 9985010 labeled Power Steering Fluid.
Consult the Parts Catalog, Owner's Manual, or Service Information (SI) for fluid recommendations.
Some of our customers and/or General Motors dealerships/Saturn Retailers may have some
concerns with DEXRON(R)-VI and DEXRON(R)-III Automatic Transmission Fluid (ATF) and
transmission warranty claims. DEXRON(R)-VI is the only approved fluid for warranty repairs for
General Motors transmissions/transaxles requiring DEXRON(R)-III and/or prior DEXRON(R)
transmission fluids (except as noted above). Please remember that the clean oil reservoirs of the
J-45096 - Flushing and Flow Tester machine should be purged of DEXRON(R)-III and filled with
DEXRON(R)-VI for testing, flushing or filling General Motors transmissions/transaxles (except as
noted above).
DEXRON(R)-VI can be used in any proportion in past model vehicles equipped with an automatic
transmission/transaxle in place of DEXRON(R)-III (i.e. topping off the fluid in the event of a repair
or fluid change). DEXRON(R)-VI is also compatible with any former version of DEXRON(R) for use
in automatic transmissions/transaxles.
DEXRON(R)-VI ATF
General Motors Powertrain has upgraded to DEXRON(R)-VI ATF with the start of 2006 vehicle
production.
Current and prior automatic transmission models that had used DEXRON(R)-III must now only use
DEXRON(R)-VI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Technical Service Bulletins
> A/T - DEXRON(R)-VI Fluid Information > Page 2985
All 2006 and future model transmissions that use DEXRON(R)-VI are to be serviced ONLY with
DEXRON(R)-VI fluid.
DEXRON(R)-VI is an improvement over DEXRON(R)-III in the following areas:
* These ATF change intervals remain the same as DEXRON(R)-III for the time being.
2006-2008 Transmission Fill and Cooler Flushing
Some new applications of the 6L80 six speed transmission will require the use of the J 45096 Flushing and Flow Tester to accomplish transmission fluid fill. The clean oil reservoir of the
machine should be purged of DEXRON(R)-III and filled with DEXRON(R)-VI.
Parts Information
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Technical Service Bulletins
> A/T - DEXRON(R)-VI Fluid Information > Page 2986
Fluid - A/T: Technical Service Bulletins A/T - Water Or Coolant Contamination Information
INFORMATION
Bulletin No.: 08-07-30-035B
Date: November 01, 2010
Subject: Information on Water or Ethylene Glycol in Transmission Fluid
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks with Automatic Transmission
Supercede: This bulletin is being revised to update model years. Please discard Corporate Bulletin
Number 08-07-30-035A (Section 07 - Transmission/Transaxle).
Water or ethylene glycol in automatic transmission fluid (ATF) is harmful to internal transmission
components and will have a negative effect on reliability and durability of these parts. Water or
ethylene glycol in ATF will also change the friction of the clutches, frequently resulting in shudder
during engagement or gear changes, especially during torque converter clutch engagement.
Indications of water in the ATF may include:
- ATF blowing out of the transmission vent tube.
- ATF may appear cloudy or, in cases of extreme contamination, have the appearance of a
strawberry milkshake.
- Visible water in the oil pan.
- A milky white substance inside the pan area.
- Spacer plate gaskets that appear to be glued to the valve body face or case.
- Spacer plate gaskets that appear to be swollen or wrinkled in areas where they are not
compressed.
- Rust on internal transmission iron/steel components.
If water in the ATF has been found and the source of the water entry has not been identified, or if a
leaking in-radiator transmission oil cooler is suspected (with no evidence of cross-contamination in
the coolant recovery reservoir), a simple and quick test kit is available that detects the presence of
ethylene glycol in ATF. The "Gly-Tek" test kit, available from the Nelco Company, should be
obtained and the ATF tested to make an accurate decision on the need for radiator replacement.
This can help to prevent customer comebacks if the in-radiator transmission oil cooler is leaking
and reduce repair expenses by avoiding radiator replacement if the cooler is not leaking. These
test kits can be obtained from:
Nelco Company
Test kits can be ordered by phone or through the website listed above. Orders are shipped
standard delivery time but can be shipped on a next day delivery basis for an extra charge. One
test kit will complete 10 individual fluid sample tests. For vehicles repaired under warranty, the cost
of the complete test kit plus shipping charges should be divided by 10 and submitted on the
warranty claim as a net item.
The transmission should be repaired or replaced based on the normal cost comparison procedure.
Important If water or coolant is found in the transmission, the following components MUST be
replaced.
- Replace all of the rubber-type seals.
- Replace all of the composition-faced clutch plates and/or bands.
- Replace all of the nylon parts.
- Replace the torque converter.
- Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
Important The following steps must be completed when repairing or replacing.
Flush and flow check the transmission oil cooler using J 45096. Refer to Corporate Bulletin Number
02-07-30-052F- Automatic Transmission Oil Cooler Flush and Flow Test Essential Tool J 45096
TransFlow.
- Thoroughly inspect the engine cooling system and hoses and clean/repair as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Technical Service Bulletins
> A/T - DEXRON(R)-VI Fluid Information > Page 2987
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Technical Service Bulletins
> A/T - DEXRON(R)-VI Fluid Information > Page 2988
Fluid - A/T: Technical Service Bulletins A/T - Oil Cooler Flushing/Flow Check Procedures
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 99-07-30-017A
Date: February, 2003
INFORMATION
Subject: Automatic Transmission Oil Cooler Flushing and Flow Check Procedures
Models: 2003 and Prior GM Light Duty Trucks 2003 HUMMER H2 with Allison(R) Automatic
Transmission (RPO M74)
This bulletin revises bulletin 99-07-30-017 to reflect the release of the new Transflow(R) J 45096
Transmission Cooling System Service Tool. The Transflow(R) Transmission Cooling System
Service Tool is to be used for all vehicles. Please discard Corporate Bulletin Number 99-07-30-017
(Section 07 - Transmission/Transaxle). Refer to Corporate Bulletin Number 02-07-30-052.
Important:
If you were sent here by the instruction booklet for the J 45096 TransFlow(R) machine, note that
the table has been moved to Corporate Bulletin Number 02-07-30-052.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Specifications > Capacity
Specifications
Fluid - A/T: Capacity Specifications
Transmission Fluid 4L60-E Pan Removal ...........................................................................................
.......................................................................................................... 4.7L (5.0 Qt) Overhaul ..............
..............................................................................................................................................................
............................ 10.6L (11.0 Qt) 4L80-E Dry ....................................................................................
............................................................................................................................ 12.8L (13.5 Qt) Pan
Removal ..............................................................................................................................................
....................................................... 7.8L (7.7 Qt)
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Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Specifications > Capacity
Specifications > Page 2991
Fluid - A/T: Fluid Type Specifications
Transmission Fluid Type
Type .....................................................................................................................................................
...................................... DEXRON III or Equivalent
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E
Fluid - A/T: Service and Repair 4L60-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
Caution: When the transmission is at operating temperatures, take necessary precautions when
removing the drain plug, to avoid being burned by draining field.
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the
transmission oil pan. 3. Remove the oil pan drain plug, if equipped. 4. If necessary, remove the
bolts and position aside the range selector cable bracket for clearance while lowering the pan. It is
not necessary to
remove the cable from the lever or bracket.
5. Remove the oil pan bolts from the front and sides of the pan only. 6. Loosen the rear oil pan
bolts approximately 4 turns. 7. Lightly tap the oil pan with a rubber mallet in order to loosen the pan
to allow the fluid to drain.
8. Remove the remaining oil pan bolts.
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Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E > Page 2994
9. Remove the oil pan and the gasket.
10. Grasp firmly while pulling down with a twisting motion in order to remove the filter.
11. Remove the filter seal. The filter seal may be stuck in the pump; if necessary, carefully use
pliers or another suitable tool to remove the seal. 12. Discard the seal. 13. Inspect the fluid color.
14. Inspect the filter. Pry the metal crimping away from the top of the filter and pull apart. The filter
may contain the following evidence for root cause
diagnosis: ^
Clutch material
^ Bronze slivers indicating bushing wear
^ Steel particles
15. Clean the transmission case and the oil pan gasket surfaces with solvent, and air dry. You must
remove all traces of the old gasket material.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E > Page 2995
1. Coat the new filter seal with automatic transmission fluid. 2. Install the new filter seal into the
transmission case. Tap the seal into place using a suitable size socket. 3. Install the new filter into
the case.
4. Install the oil pan and a new gasket.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan bolts.
^ Tighten the oil pan to transmission case bolts alternately and evenly to 11 Nm (97 inch lbs.).
6. If previously removed, install the range selector cable bracket and bolts.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Apply a small amount of sealant GM P/N 12346004 to the threads of the oil pan drain plug, if
equipped. 8. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E > Page 2996
9. Lower the vehicle.
10. Fill the transmission to the proper level with DEXRON III transmission fluid. 11. Check the
COLD fluid level reading for initial fill only. 12. Inspect the oil pan gasket for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E > Page 2997
Fluid - A/T: Service and Repair 4L80-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the transmission oil pan. 3.
Remove the oil pan drain plug, if equipped. 4. Remove the oil pan bolts. 5. Remove the oil pan. 6.
Remove the gasket. 7. Remove the magnet.
8. Remove the oil filter. 9. Remove the filter neck seal.
10. The transmission oil pan gasket is reusable. Inspect the gasket and replace as needed. 11.
Clean the transmission case and the oil pan gasket surfaces with solvent.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - A/T > Component Information > Service and Repair >
4L60-E > Page 2998
1. Install the filter neck seal. 2. Install the oil filter.
3. Install the oil pan gasket to the pan. 4. Install the magnet into the bottom of the pan.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan to the transmission with seventeen bolts.
^ Tighten the oil pan bolts to 11 Nm (97 inch lbs.).
6. Apply a small amount of sealant GM P/N 12346004 to the treads of the drain plug, if equipped.
7. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
8. Lower the vehicle. 9. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Differential > Component Information > Technical Service
Bulletins > Drivetrain - Front Drive Axle Lubrication Update
Fluid - Differential: Technical Service Bulletins Drivetrain - Front Drive Axle Lubrication Update
Bulletin No.: 05-00-90-010
Date: December 07, 2005
SERVICE MANUAL UPDATE
Subject: Revised Front Drive Axle Carrier Lubricant Information
Models: 1999-2005 Light Duty Trucks 2003-2005 HUMMER H2 2005 Saab 9-7X
with Four-Wheel or All-Wheel Drive and
Separate Front Drive Axle Carriers
This bulletin is being issued to revise the front drive axle carrier lubricant specification in the
Maintenance and Lubrication and the Front Drive Axle sub-sections of the Service Manual. Please
replace the current information in the Service Manual with the following information.
The information has been updated within SI. If you are using a paper version of this Service
Manual, please make a reference to this bulletin on the affected page.
This information also updates the information found in the Owner Manual.
Important:
Front drive axle carriers do not require periodic lubricant replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Differential > Component Information > Technical Service
Bulletins > Drivetrain - Front Drive Axle Lubrication Update > Page 3003
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Differential > Component Information > Specifications >
Capacity Specifications
Fluid - Differential: Capacity Specifications
Differential Oil Capacity
Front Drive Axle (8.25") .......................................................................................................................
..................................................... 1.66 L (1.75 qts.) Front Drive Axle (9.25") .....................................
....................................................................................................................................... 1.73 L (1.83
qts.) Rear Drive Axle (8.6") ..................................................................................................................
............................................................. 2.28 L (2.41 qts.) Rear Drive Axle (9.5") ...............................
.................................................................................................................................................. 2.6 L
(2.75 qts.) Rear Drive Axle (10.5") ......................................................................................................
......................................................................... 2.6 L (2.75 qts.) Rear Drive Axle (11.5") ...................
..........................................................................................................................................................
3.62 L (3.83 qts.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Differential > Component Information > Specifications >
Capacity Specifications > Page 3006
Fluid - Differential: Fluid Type Specifications
Differential Fluid Type
Differential Fluid Type
Front (S4WD) Grade ...........................................................................................................................
.................................................................................................. GL-5 Viscosity ..................................
..............................................................................................................................................................
................... 80W-90 Front (F4WD) Grade ..........................................................................................
............................................................................................................................. Synthetic Viscosity .
..............................................................................................................................................................
.................................................... 75W-90 Rear Grade .......................................................................
................................................................................................................................................
Synthetic Viscosity ...............................................................................................................................
.................................................................................... 75W-90
Front Differential
Differential Fluid Type
The content of this article reflects the changes identified in TSB number 05-00-90-010 dated
December 07, 2005.
1999-2004 7.25 Inch (Blazer, Jimmy, S-10, Sonoma, Astro, Safari) Grade ........................................
..............................................................................................................................................................
....................... GL-5 Viscosity .............................................................................................................
...................................................................................................... 80W-90 2002-2005 7.25 Inch
(Trailblazer, Envoy, Bravada, Rainier Grade .......................................................................................
................................................................................................................................ Synthetic
Viscosity ..............................................................................................................................................
..................................................................... 75W-90 8.25 Inch With Selectable 4WD Grade ............
..............................................................................................................................................................
................................................... GL-5 Viscosity .................................................................................
.................................................................................................................................. 80W-90 8.25
Inch With AWD Grade .........................................................................................................................
.............................................................................................. Synthetic Viscosity ................................
..............................................................................................................................................................
..................... 75W-90 1999-2001 9.25 Inch Grade .............................................................................
................................................................................................................................................ GL-5
Viscosity ..............................................................................................................................................
..................................................................... 80W-90 2002-2005 9.25 Inch Grade .............................
..............................................................................................................................................................
............................ Synthetic Viscosity ..................................................................................................
................................................................................................................. 75W-90
Front Drive Axle
Differential Fluid Type
The content of this article reflects the changes identified in TSB number 05-00-90-010 dated
December 07, 2005.
1999-2004 7.25 Inch (Blazer, Jimmy, S-10, Sonoma, Astro, Safari) Grade ........................................
..............................................................................................................................................................
....................... GL-5 Viscosity .............................................................................................................
...................................................................................................... 80W-90 2002-2005 7.25 Inch
(Trailblazer, Envoy, Bravada, Rainier Grade .......................................................................................
................................................................................................................................ Synthetic
Viscosity ..............................................................................................................................................
..................................................................... 75W-90 8.25 Inch With Selectable 4WD Grade ............
..............................................................................................................................................................
................................................... GL-5 Viscosity .................................................................................
.................................................................................................................................. 80W-90 8.25
Inch With AWD Grade .........................................................................................................................
.............................................................................................. Synthetic Viscosity ................................
..............................................................................................................................................................
..................... 75W-90 1999-2001 9.25 Inch Grade .............................................................................
................................................................................................................................................ GL-5
Viscosity ..............................................................................................................................................
..................................................................... 80W-90 2002-2005 9.25 Inch Grade .............................
..............................................................................................................................................................
............................ Synthetic Viscosity ..................................................................................................
................................................................................................................. 75W-90
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Specifications >
Capacity Specifications
Fluid - Transfer Case: Capacity Specifications
Transfer Case NVG 149 ......................................................................................................................
..................................................................................... 2.3L (2.4 Qt) NVG 236-246 ...........................
..............................................................................................................................................................
........... 1.9L (2.0 Qt)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Specifications >
Capacity Specifications > Page 3011
Fluid - Transfer Case: Fluid Type Specifications
Transfer Case
NVG 149 ..............................................................................................................................................
..................... Auto-Trak II Fluid GM P/N 12378508
NVG 236/246
..........................................................................................................................................................
Auto-Trak II Fluid GM P/N 12378508
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Service and
Repair > NVG 149-NP (One Speed Automatic)
Fluid - Transfer Case: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Fluid Replacement
Removal Procedure
Important: When performing the following service procedures, use only hand tools to remove and
install the fill or drain plugs.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shields from the cross
member (if equipped). 3. Remove the fill plug from the transfer case.
Important: When draining the transfer case, make sure that an approved drain pan is used.
4. Remove the drain plug from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Service and
Repair > NVG 149-NP (One Speed Automatic) > Page 3014
Important: If the drain or fill plug have to be replaced, used only aluminum replacement drain plugs.
1. Install the drain plug in the transfer case.
^ Tighten the drain plug to 20 Nm (15 ft. lbs.).
2. Fill the transfer case to the bottom of the fill hole with the proper fluid.
3. Install the fill plug.
^ Tighten the drain plug to 20 Nm (15 ft. lbs.).
4. Install the transfer case shield to the cross member. 5. Lower the vehicle. Refer to Vehicle
Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Service and
Repair > NVG 149-NP (One Speed Automatic) > Page 3015
Fluid - Transfer Case: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Fluid Replacement
Removal Procedure
Important: When performing the following service procedures, use only hand tools in order to
remove and install the fill or drain plugs. Always start the plugs by hand in order to prevent cross
threading.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shields. 3. Remove the
transfer case fill plug.
4. Remove the transfer case drain plug.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Important: If the drain or fill plug have to be replaced, used only aluminum replacement drain plugs.
Steel plugs will react with the magnesium of
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Fluid - Transfer Case > Component Information > Service and
Repair > NVG 149-NP (One Speed Automatic) > Page 3016
the transfer case.
1. Install the transfer case drain plug.
^ Tighten the transfer case drain plug to 20 Nm (15 ft. lbs.).
2. Fill the transfer case to the bottom of the fill hole with the approved fluid. 3. Install the transfer
case fill plug.
^ Tighten the transfer case fill plug to 20 Nm (15 ft. lbs.).
4. Install the transfer case shield. 5. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Technical Service Bulletins
> Engine - GM dexos 1 and dexos 2(R) Oil Specifications
Engine Oil: Technical Service Bulletins Engine - GM dexos 1 and dexos 2(R) Oil Specifications
INFORMATION
Bulletin No.: 11-00-90-001
Date: March 14, 2011
Subject: Global Information for GM dexos1(TM) and GM dexos2(TM) Engine Oil Specifications for
Spark Ignited and Diesel Engines, Available Licensed Brands, and Service Fill for Adding or
Complete Oil Change
Models:
2012 and Prior GM Passenger Cars and Trucks Excluding All Vehicles Equipped with
Duramax(TM) Diesel Engines
GM dexos 1(TM) Information Center Website
Refer to the following General Motors website for dexos 1(TM) information about the different
licensed brands that are currently available: http://www.gmdexos.com
GM dexos 1(TM) Engine Oil Trademark and Icons
The dexos(TM) specification and trademarks are exclusive to General Motors, LLC.
Only those oils displaying the dexos‹›(TM) trademark and icon on the front label meet the
demanding performance requirements and stringent quality standards set forth in the dexos‹›(TM)
specification.
Look on the front label for any of the logos shown above to identify an authorized, licensed dexos
1(TM) engine oil.
GM dexos 1(TM) Engine Oil Specification
Important General Motors dexos 1(TM) engine oil specification replaces the previous General
Motors specifications GM6094M, GM4718M and GM-LL-A-025 for most GM gasoline engines. The
oil specified for use in GM passenger cars and trucks, PRIOR to the 2011 model year remains
acceptable for those previous vehicles. However, dexos 1(TM) is backward compatible and can be
used in those older vehicles.
In North America, starting with the 2011 model year, GM introduced dexos 1(TM) certified engine
oil as a factory fill and service fill for gasoline engines. The reasons for the new engine oil
specification are as follows:
- To meet environmental goals such as increasing fuel efficiency and reducing engine emissions.
- To promote long engine life.
- To minimize the number of engine oil changes in order to help meet the goal of lessening the
industry's overall dependence on crude oil.
dexos 1(TM) is a GM-developed engine oil specification that has been designed to provide the
following benefits:
- Further improve fuel economy, to meet future corporate average fuel economy (CAFE)
requirements and fuel economy retention by allowing the oil to maintain its fuel economy benefits
throughout the life of the oil.
- More robust formulations for added engine protection and aeration performance.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Technical Service Bulletins
> Engine - GM dexos 1 and dexos 2(R) Oil Specifications > Page 3021
- Support the GM Oil Life System, thereby minimizing the replacement of engine oil, before its life
has been depleted.
- Reduce the duplication of requirements for a large number of internal GM engine oil
specifications.
International Lubricants Standardization and Approval Committee (ILSAC)
GF-5 Standard
In addition to GM dexos 1(TM), a new International Lubricants Standardization and Approval
Committee (ILSAC) standard called GF-5, was introduced in October 2010.
- There will be a corresponding API category, called: SN Resource Conserving. The current GF-4
standard was put in place in 2004 and will become obsolete in October 2011. Similar to dexos
1(TM), the GF-5 standard will use a new fuel economy test, Sequence VID, which demands a
statistically significant increase in fuel economy versus the Sequence VIB test that was used for
GF-4.
- It is expected that all dexos 1(TM) approved oils will be capable of meeting the GF-5 standard.
However, not all GF-5 engine oils will be capable of meeting the dexos 1(TM) specification.
- Like dexos(TM), the new ILSAC GF-5 standard will call for more sophisticated additives. The API
will begin licensing marketers during October 2010, to produce and distribute GF-5 certified
products, which are expected to include SAE 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30 oils.
Corporate Average Fuel Economy (CAFE) Requirements Effect on Fuel Economy
Since CAFE standards were first introduced in 1974, the fuel economy of cars has more than
doubled, while the fuel economy of light trucks has increased by more than 50 percent. Proposed
CAFE standards call for a continuation of increased fuel economy in new cars and trucks. To meet
these future requirements, all aspects of vehicle operation are being looked at more critically than
ever before.
New technology being introduced in GM vehicles designed to increase vehicle efficiency and fuel
economy include direct injection, cam phasing, turbocharging and active fuel management (AFM).
The demands of these new technologies on engine oil also are taken into consideration when
determining new oil specifications. AFM for example can help to achieve improved fuel economy.
However alternately deactivating and activating the cylinders by not allowing the intake and
exhaust valves to open contributes to additional stress on the engine oil.
Another industry trend for meeting tough fuel economy mandates has been a shift toward lower
viscosity oils.
dexos 1(TM) will eventually be offered in several viscosity grades in accordance with engine needs:
SAE 0W-20, 5W-20, 0W-30 and 5W-30.
Using the right viscosity grade oil is critical for proper engine performance. Always refer to the
Maintenance section of a vehicle Owner Manual for the proper viscosity grade for the engine being
serviced.
GM Oil Life System in Conjunction With dexos (TM) Supports Extended Oil Change Intervals
To help conserve oil while maintaining engine protection, many GM vehicles are equipped with the
GM Oil Life System. This system can provide oil change intervals that exceed the traditional 3,000
mile (4,830 km) recommendation.
The dexos (TM) specification, with its requirements for improved oil robustness, compliments the
GM Oil Life System by supporting extended oil change intervals over the lifetime of a vehicle.
If all GM customers with GM Oil Life System equipped vehicles would use the system as intended,
GM estimates that more than 100 million gallons of oil could be saved annually.
GM dexos 2(TM) Information Center Website
Refer to the following General Motors website for dexos 2(TM) information about the different
licensed brands that are currently available: http://www.gmdexos.com
GM dexos 2(TM) Engine Oil Trademark and Icons
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Technical Service Bulletins
> Engine - GM dexos 1 and dexos 2(R) Oil Specifications > Page 3022
The dexos (TM) specification and trademarks are exclusive to General Motors, LLC.
Only those oils displaying the dexos (TM) trademark and icon on the front label meet the
demanding performance requirements and stringent quality standards set forth in the dexos
(TM)specification.
Look on the front label for any of the logos shown above to identify an authorized, licensed dexos
2(TM) engine oil.
GM dexos 2(TM) Engine Oil Specification
- dexos 2(TM) is approved and recommended by GM for use in Europe starting in model year 2010
vehicles, regardless of where the vehicle was manufactured.
- dexos 2(TM) is the recommended service fill oil for European gasoline engines.
Important The Duramax(TM) diesel engine is the exception and requires lubricants meeting
specification CJ-4.
- dexos 2(TM) is the recommended service fill oil for European light-duty diesel engines and
replaces GM-LL-B-025 and GM-LL-A-025.
- dexos 2(TM) protects diesel engines from harmful soot deposits and is designed with limits on
certain chemical components to prolong catalyst life and protect expensive emission reduction
systems. It is a robust oil, resisting degradation between oil changes and maintaining optimum
performance longer.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Specifications > Capacity
Specifications
Engine Oil: Capacity Specifications
Engine Oil
With Filter Change ...............................................................................................................................
............................................................. 5.7L (6.0 Qt)
NOTE: ALL capacity specifications are approximate. When replacing or adding fluids, fill to the
recommended level and recheck fluid level.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Specifications > Capacity
Specifications > Page 3025
Engine Oil: Fluid Type Specifications
Engine Oil
API Classification .................................................................................................................................
........................................ Look for Starburst Symbol Grade ...............................................................
......................................................................................................................................... 5W-30
(preferred) Above -18° C (0° F) ...........................................................................................................
........................................................ 10W-30, 5W-30 (preferred)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Specifications > Page 3026
Engine Oil: Service and Repair
Engine Oil and Oil Filter Replacement
Removal Procedure
Important: In order to completely drain the oil from the oil pan internal baffling, the bottom of the oil
pan must be level during the oil drain procedure.
1. Open the hood. 2. Remove the oil fill cap. 3. Raise and suitably support the vehicle. Refer to
Vehicle Lifting. 4. Place a oil drain pan under the oil pan drain plug. 5. Remove the oil pan drain
plug. 6. Drain the engine oil. 7. Wipe the excess oil from the drain plug hole and plug.
8. Remove the oil filter from the engine block.
Important: Check the old oil filter to ensure that the filter seal is not left on the engine block.
9. Wipe the excess oil from the oil filter mounting.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Engine Oil > Component Information > Specifications > Page 3027
1. Lubricate the oil filter seal with clean engine oil.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the oil filter to the engine block.
- Tighten the oil filter to 30 Nm (22 ft. lbs.).
3. install the oil drain plug to the engine block.
- Tighten the oil pan drain plug to 25 Nm (18 ft. lbs.).
4. Lower the vehicle. 5. Fill the crankcase with the proper quantity and grade of engine oil. 6.
Remove the oil level indicator. 7. Wipe the indicator with a clean cloth. 8. Install the oil level
indicator. 9. Remove the oil level indicator in order to check the level.
10. Add oil if necessary: 11. Close the hood.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Power Steering Fluid > Component Information > Specifications
Power Steering Fluid: Specifications
Power Steering System GM Power Steering Fluid (GM Part No. 1052884 - 1 pint, 1050017 - 1
quart, or equivalent).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Technical Service Bulletins
> A/C - Refrigerant Recovery/Recycling/Equipment
Refrigerant: Technical Service Bulletins A/C - Refrigerant Recovery/Recycling/Equipment
Bulletin No.: 08-01-38-001
Date: January 25, 2008
INFORMATION
Subject: Information On New GE-48800 CoolTech Refrigerant Recovery/Recharge Equipment
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks (Including Saturn) 2008 and
Prior HUMMER H2, H3 2005-2008 Saab 9-7X
Attention:
This bulletin is being issued to announce the release of GM approved Air Conditioning (A/C)
Refrigerant Recovery and Recharging Equipment that meets the new Society of Automotive
Engineers (SAE) J2788 Refrigerant Recovery Standards. The ACR2000 (J-43600) cannot be
manufactured in its current state after December 2007 and will be superseded by GE-48800.
The new J2788 standard does not require that GM Dealers replace their ACR2000 units.
ACR2000's currently in use are very capable of servicing today's refrigerant systems when used
correctly and can continue to be used. Details regarding the new SAE J2788 standard are outlined
in GM Bulletin 07-01-38-004.
Effective February 1 2008, new A/C Refrigerant Recovery/Recharging equipment (P/N GE-48800)
will be released as a required replacement for the previously essential ACR2000 (J-43600). This
equipment is SAE J2788 compliant and meets GM requirements for A/C Refrigerant System
Repairs on all General Motors vehicles, including Hybrid systems with Polyolester (POE)
refrigerant oil. This equipment will not be shipped as an essential tool to GM Dealerships.
In addition, this equipment is Hybrid compliant and designed to prevent oil cross contamination
when servicing Hybrid vehicles with Electric A/C Compressors that use POE refrigerant oil.
The ACR2000 (J-43600) will need to be retrofitted with a J-43600-50 (Hose - ACR2000 Oil Flush
Loop) to be able to perform Hybrid A/C service work. All Hybrid dealers will receive the J-43600-50,
with installation instructions, as a component of the Hybrid essential tool package. Dealerships that
do not sell Hybrids, but may need to service Hybrids, can obtain J-43600-50 from SPX Kent Moore.
Refer to GM Bulletin 08-01-39-001 for the ACR2000 Hose Flush procedure.
The High Voltage (HV) electric A/C compressor used on Two Mode Hybrid vehicles uses a
Polyolester (POE) refrigerant oil instead of a Polyalkylene Glycol (PAG) synthetic refrigerant oil.
This is due to the better electrical resistance of the POE oil and its ability to provide HV isolation.
Failure to flush the hoses before adding refrigerant to a Hybrid vehicle with an electric A/C
compressor may result in an unacceptable amount of PAG oil entering the refrigerant system. It
may cause a Battery Energy Control Module Hybrid Battery Voltage System Isolation Lost
Diagnostic Trouble Code (DTC P1AE7) to be set. Additionally, the A/C system warranty will be
voided.
Warranty Submission Requirements
The Electronically Generated Repair Data (snapshot summary) and printer functions have been
eliminated from the GE-48800. The VGA display and temperature probes were eliminated to
reduce equipment costs. As a result, effective immediately the 18 digit "Snapshot/Charge
Summary" code is no longer required for Air Conditioning (A/C) refrigerant system repairs that are
submitted for warranty reimbursement. The charge summary data from before and after system
repairs will continue to required, but documented on the repair order only. Both high and low
pressures and the recovery and charge amounts should be noted during the repair and entered on
the repair order. If using ACR2000 (J-43600), the "Snapshot/Charge Summary" printouts should
continue to be attached to the shops copy of the repair order.
The labor codes that are affected by this requirement are D3000 through D4500.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Technical Service Bulletins
> A/C - Refrigerant Recovery/Recycling/Equipment > Page 3035
Refrigerant: Technical Service Bulletins A/C - Contaminated R134A Refrigerant
Bulletin No.: 06-01-39-007
Date: July 25, 2006
INFORMATION
Subject: Contaminated R134a Refrigerant Found on Market for Automotive Air-Conditioning
Systems
Models: 2007 and Prior GM Passenger Cars and Trucks (including Saturn) 2007 and Prior
HUMMER H2, H3 2007 and Prior Saab 9-7X
Attention:
This bulletin should be directed to the Service Manager as well as the Parts Manager.
Commercially Available Contaminated R134a Refrigerant
Impurities have been found in new commercially available containers of R134a. High levels of
contaminates may cause decreased performance, and be detrimental to some air-conditioning
components. Accompanying these contaminates has been high levels of moisture.
Tip:
Excessive moisture may cause system concerns such as orifice tube freeze-up and reduced
performance.
Industry Reaction: New Industry Purity Standards
Due to the potential availability of these lower quality refrigerants, the Society of Automotive
Engineers (SAE), and the Air Conditioning and Refrigeration Industry (ARI) are in the process of
instituting reliable standards that will be carried on the labels of future R134a refrigerant containers.
This identifying symbol will be your assurance of a product that conforms to the minimum standard
for OEM Automotive Air-Conditioning use.
How Can You Protect Yourself Today?
It is recommended to use GM or ACDelco(R) sourced refrigerants for all A/C repair work. These
refrigerants meet General Motors own internal standards for quality and purity, insuring that your
completed repairs are as good as the way it left the factory.
Parts Information
The part numbers shown are available through GMSPO or ACDelco(R). The nearest ACDelco(R)
distributor in your area can be found by calling 1-800-223-3526 (U.S. Only).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Technical Service Bulletins
> A/C - Refrigerant Recovery/Recycling/Equipment > Page 3036
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Specifications > Capacity
Specifications
Refrigerant: Capacity Specifications
Refrigerant Charge
Refrigerant Charge ..............................................................................................................................
............................................................ 0.8 kg (1.8 lb) Refrigerant Charge Utility with Front and Rear
A/C ....................................................................................................................................... 1.2 kg
(2.7 lb) Refrigerant Charge Suburban with Front and Rear A/C
.................................................................................................................................. 1.4 kg (3.0 lb)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Specifications > Capacity
Specifications > Page 3039
Refrigerant: Fluid Type Specifications
Refrigerant Type ..................................................................................................................................
..................................................................... R-134a
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Specifications > Page 3040
Refrigerant: Service and Repair
If oil was removed from the A/C system during the recovery process or due to component
replacement, the oil must be replenished. Oil can be injected into a charged system using J 45037
For the proper quantities of oil to add to the A/C refrigerant system, refer to Refrigerant System
Capacities.
Flushing TOOLS REQUIRED J 43600 Air Conditioning Service Center
- J 45268 Flush Adapter Kit
- J 41447 Leak Detection Dye
- J 41459 Leak Detection Dye Injector
- J 42220 Universal Leak Detection Lamp
IMPORTANT: Flushing is not intended to remove metal from the A/C system.
Flushing is intended to remove the following: Contaminated PAG oil
- Desiccant, following a desiccant bag failure
- Overcharge of PAG oil
- Refrigerant contamination
IMPORTANT: Warmer engine or ambient temperature decreases the refrigerant recovery time
during the A/C flush procedure.
1. Recover the refrigerant. Refer to Refrigerant Recovery and Recharging. 2. Remove the orifice
tube. 3. Connect the A/C lines with the orifice tube removed. 4. Remove the A/C compressor. 5.
Inspect the end of the suction hose for a suction screen. 6. Remove the suction screen, if installed.
7. Install the J 45268-4 to the A/C compressor suction hose. 8. install the J 45268-5 to the A/C
compressor discharge hose. 9. Forward flow refrigerant flushing is recommended for contaminated
refrigerant or PAG oil. Perform the following procedure:
IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve
from the filter.
9.1. Service the filter with AC P/N GF 470, before each flush. Connect the J 45268-1 flush filter to
the suction port of the J 45268-4 flush adapter.
9.2. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter.
9.3. Connect the red hose from the J 43600 to the J 45268-5 flush adapter.
10. Reverse flow refrigerant flushing is recommended for desiccant bag failure.
Perform the following procedure and replace the accumulator when the flush procedure is
complete.
IMPORTANT: The filter inside the J 45268-1 is serviceable. Remove and discard the check valve
from the filter.
10.1. Service the filter with AC P/N GF 470, before each flush.
Connect the J 45268-1 flush filter to the discharge port of the J 45268-5 flush adapter.
10.2. Connect the blue hose from the J 43600 to the J 45268-1 flush filter adapter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Specifications > Page 3041
10.3. Connect the red hose from the J 43600 to the suction port of the J 45268-4 flush adapter.
11. Flush the front A/C system. Follow the instructions supplied with the J 43600.
Close the valve on the external refrigerant tank, before starting the flush process.
IMPORTANT: Flush the front A/C system before flushing the auxiliary A/C system.
12. If the vehicle is equipped with rear A/C, flush the auxiliary A/C system separately. 13. Cut the
orifice tube frame and screen, enough to access the end of the orifice tube Pinch off the orifice
tube.
IMPORTANT: Pinch off the orifice tube in order to prevent refrigerant flow to the front system
during the auxiliary system flush.
14. Install the pinched orifice tube. 15. Remove the auxiliary TXV. 16. Install the J 45268-104.
IMPORTANT: The auxiliary evaporator core can be flushed without totally reassembling into the
auxiliary HVAC module.
17. Install the auxiliary evaporator core to the A/C lines. 18. Raise the vehicle. Refer to Lifting and
Jacking the Vehicle on page. 19. Connect the auxiliary A/C lines to the auxiliary evaporator core.
20. Lower the vehicle. 21. Flush the auxiliary A/C system. Follow the instructions supplied with the
J 43600. 22. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 23. Remove the auxiliary
A/C lines from the auxiliary evaporator core. 24. Lower the vehicle. 25. Remove the J 45268-104.
26. Inspect the TXV for debris. Clean or replace as needed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant > Component Information > Specifications > Page 3042
27. Install the auxiliary TXV. 28. Remove the J 45268-4 from the A/C compressor suction hose. 29.
Remove the J 45268-5 from the A/C compressor discharge hose.
- Drain the PAG oil from the A/C compressor, through the suction and discharge ports.
- Rotate the compressor input shaft to assist in draining the PAG oil from the A/C compressor.
30. Install the A/C compressor. 31. Install a new orifice tube. 32. Evacuate and recharge the A/C
system. Refer to Refrigerant Recovery and Recharging.
IMPORTANT: Flushing will remove all of the PAG oil from the A/C system.
33. Add the total system capacity of PAG oil to the A/C system. Refer to Refrigerant System
Capacities.
IMPORTANT: Flushing will remove the fluorescent leak detection dye from the A/C system.
34. Add one bottle of J 41447 using the J 41459. 35. Leak test the fittings using the J 42220.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant Oil > Component Information > Technical Service
Bulletins > A/C - New PAG Oil
Refrigerant Oil: Technical Service Bulletins A/C - New PAG Oil
Bulletin No.: 02-01-39-004B
Date: November 16, 2005
INFORMATION
Subject: New PAG Oil Released
Models: 2006 and Prior GM Passenger Cars and Trucks (Including Saturn) 2003-2006 HUMMER
H2 2006 HUMMER H3 2005-2006 Saab 9-7X
Built With R-134a Refrigeration System
All Air Conditioning Compressor Types (Excluding R4 and A6 Type Compressors)
Supercede:
This bulletin is being revised to change the PAG oil part number used for R4 and A6 compressors
with R-134a refrigerant systems. Please discard Corporate Bulletin Number 02-01-39-004A
(Section 01 - HVAC).
All General Motors vehicles built with R-134a refrigerant systems shall now be serviced with GM
Universal PAG Oil (excluding vehicles equipped with an R4 or A6 compressor).
R4 and A6 compressors with R-134a refrigerant systems shall use PAG OIL, GM P/N 12356151
(A/C Delco part number 15-118) (in Canada, use P/N 10953486).
Important:
The PAG oil referenced in this bulletin is formulated with specific additive packages that meet
General Motors specifications and use of another oil may void the A/C systems warranty.
Use this new PAG oil when servicing the A/C system on the vehicles listed above. Oil packaged in
an 8 oz tube should be installed using A/C Oil Injector, J 45037. Refer to the HVAC Section of
Service Information for detailed information on Oil Balancing and Capacities.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant Oil > Component Information > Specifications >
Capacity Specifications
Refrigerant Oil: Capacity Specifications
If the refrigerant oil was removed from the A/C system during the recovery process or during the
component replacement, the refrigerant oil must be replenished. Add the refrigerant oil as
indicated. If more than the specified amount of PAG oil was drained from a component, add the
equal amount of oil drained.
Accumulator .........................................................................................................................................
.......................................................................... 60 ml Compressor ....................................................
..............................................................................................................................................................
.. 60 ml Condenser ..............................................................................................................................
........................................................................................ 30 ml Evaporator ........................................
..............................................................................................................................................................
................ 90 ml Evaporator (Rear) .....................................................................................................
..................................................................................................... 90 ml Abrupt Loss ..........................
..............................................................................................................................................................
............................ 90 ml
NOTE: Replacement compressors do not have any oil in the compressor. Add the correct amount
of oil to the replacement compressor before replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fluids > Refrigerant Oil > Component Information > Specifications >
Capacity Specifications > Page 3049
Refrigerant Oil: Fluid Type Specifications
Internal Lubricant .............................................................................................................................
Poly-Alkaline Glycol (PAG) Synthetic Refrigerant Oil
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure
Brake Bleeding: Service and Repair ABS Automated Bleed Procedure
W/JL4
ABS Automated Bleed Procedure (W/JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure is ONLY to be performed on vehicles equipped with option code JL4,
Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this bleeding
procedure. If you have not yet performed the base hydraulic brake system bleeding procedure,
refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool. 2. Apply the park brake fully. 3. Start the engine and allow the engine to idle.
4. Depress the brake pedal firmly and maintain steady pressure on the pedal. 5. From the VSES
Special Functions menu on the scan tool, select the Automated Bleed procedure. 6. Send the
automated bleed command by pressing the On key on the scan tool.
After initiating the automated bleed procedure, the brake pedal will drop and then pulse back up, 8
times, while the LPA is being purged of any trapped air.
7. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT 3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half full during this bleeding procedure and add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm, when cap removal is necessary.
8. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 9.
Install a transparent hose over the end of the bleeder valve.
10. Submerge the open end of the transparent hose into a transparent container partially filled with
Delco Supreme II, GM P/N 12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
11. Have an assistant slowly depress the brake pedal and maintain pressure on the pedal. 12.
Loosen the bleeder valve to purge air from the wheel hydraulic circuit. 13. Tighten the bleeder
valve when full brake pedal travel has occurred. 14. Have the assistant slowly release the brake
pedal. Wait 5 seconds before proceeding to the next step. 15. Repeat steps 11-14 until all air is
purged from the same wheel hydraulic circuit. 16. After all air has been purged from the right rear
hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end wrench onto
the LEFT REAR wheel hydraulic circuit bleeder valve.
17. Repeat steps 9-15 at the left rear wheel hydraulic circuit. 18. After all air has been purged from
the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end
wrench onto
the RIGHT FRONT wheel hydraulic circuit bleeder valve.
19. Repeat steps 9-15 at the right front wheel hydraulic circuit. 20. After all air has been purged
from the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper
box-end wrench onto
the LEFT FRONT wheel hydraulic circuit bleeder valve.
21. Repeat steps 9-15 at the left front wheel hydraulic circuit. 22. Fill the brake master cylinder
reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
23. Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
24. Install a transparent hose over the end of the bleeder valve. 25. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
26. Use the procedure below to purge the Medium Pressure Accumulator (MPA) of any trapped air.
26.1. With the engine still idling, select the Bleed MPA procedure from the VSES Special Functions
menu.
26.2. Send the bleed MPA command by pressing the On key on the scan tool.
26.3. Open the LEFT FRONT wheel hydraulic circuit bleeder valve.
Important: Ensure that you fully release the brake pedal for at least 2 seconds between pedal
strokes. The amount of accumulated time between pedal strokes is calculated to deliver the most
thorough bleed of the Medium Pressure Accumulator (MPA).
26.4. Depress the brake pedal as far as possible using a smooth stroke.
26.5. Release the brake pedal using a smooth stroke.
26.6. Repeat steps 26.4-26.5 until 13 complete pedal strokes have been performed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure > Page 3054
Important: Observe the MPA switch parameter as the pedal strokes are being performed. The MPA
switch parameter should change from Uncharged to Charged several times during the first 8 or 9
strokes. After approximately 10 pedal strokes, the MPA switch parameter should remain Charged.
If the parameter does not change, repeat all of step 26.
26.7. The valves within the BPMV are active for the first 13 complete pedal strokes to enable the
MPA to be filled and discharged, forcing any trapped air out of the LEFT FRONT wheel hydraulic
circuit bleeder valve.
26.8. Continue to depress and release the brake pedal while observing the fluid within the
transparent hose. When no air is observed exiting the hydraulic system, proceed to the next step.
26.9. Depress the brake pedal and maintain pedal position.
26.10. Have an assistant tighten the bleeder valve.
26.11. Release the brake pedal.
27. Remove the scan tool from the vehicle. 28. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
29. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 30. If the
brake pedal feels spongy, repeat this entire bleed procedure. If the brake pedal still feels spongy
after repeating this procedure, inspect the
brake system for external leaks.
31. Observe the brake warning indicator to determine whether or not the indicator remains
illuminated. 32. If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to
be driven until it is diagnosed and repaired.
W/O JL4
ABS Automated Bleed Procedure (w/o JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure may be performed on all vehicles EXCEPT those equipped with option
code JL4, Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this automated
bleeding procedure. If you have not yet performed the base hydraulic brake system bleeding
procedure, refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool to the vehicle. 2. Start the engine and allow the engine to idle. 3. Depress the
brake pedal firmly and maintain steady pressure on the pedal. 4. Using the scan tool, begin the
automated bleed procedure. 5. Follow the instructions on the scan tool to complete the automated
bleed procedure. Release the brake pedal between each test sequence. 6. Turn the ignition OFF.
7. Remove the scan tool from the vehicle. 8. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
9. Bleed the hydraulic brake system.
10. With the ignition OFF, apply the brakes 3-5 times, or until the brake pedal becomes firm, in
order to deplete the brake booster power reserve. 11. Slowly depress and release the brake pedal.
Observe the feel of the brake pedal. 12. If the brake pedal feels spongy, repeat the automated
bleeding procedure. If the brake pedal still feels spongy after repeating the automated
bleeding procedure inspect the brake system for external leaks.
13. Turn the ignition key ON, with the engine OFF; check to see if the brake system warning lamp
remains illuminated. 14. If the brake system warning lamp remains illuminated, DO NOT allow the
vehicle to be driven until it is diagnosed and repaired. Refer to
Symptoms - Hydraulic Brakes.
15. Drive the vehicle to exceed 13 kPa (8 mph) to allow ABS initialization to occur. Observe brake
pedal feel. 16. If the brake pedal feels spongy, repeat the automated bleeding procedure until a
firm brake pedal is obtained.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure > Page 3055
Brake Bleeding: Service and Repair Hydraulic Brake System Bleeding
Manual
Hydraulic Brake System Bleeding (Manual)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder - after all air has been
purged from the front port of the master cylinder- loosen and separate the rear brake pipe from the
master cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT-3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm.
5. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 6.
Install a transparent hose over the end of the bleeder valve. 7. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
8. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal. 9. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
10. Tighten the bleeder valve, then have the assistant slowly release the brake pedal. 11. Wait 15
seconds, then repeat steps 8-10 until all air is purged from the same wheel hydraulic circuit. 12.
With the right rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been
purged from the right rear hydraulic circuit install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
13. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 14. With
the left rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the left rear hydraulic circuit- install a
proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
15. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 16. With
the right front wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
17. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 18. After
completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel
hydraulic circuit bleeder valves are properly
tightened.
19. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
20. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 21. If the
brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy
after repeating the bleeding procedure,
perform the following steps: 21.1.
Inspect the brake system for external leaks.
21.2. Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped
in the system.
22. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure > Page 3056
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
23. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Pressure
Hydraulic Brake System Bleeding (Pressure)
Tools Required ^
J29532 Diaphragm Type Brake Pressure Bleeder, or equivalent
^ J35589-A Brake Pressure Bleeder Adapter
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder- after all air has been purged
from the front port of the master cylinder - loosen and separate the rear brake pipe from the master
cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Clean the outside of the
reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
5. Install the J35589-A to the brake master cylinder reservoir. 6. Check the brake fluid level in the
J29532, or equivalent. Add Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3
brake fluid from a clean, sealed brake fluid container as necessary to bring the level to
approximately the half-full point.
7. Connect the J29532, or equivalent, to the J35589-A. 8. Charge the J29532, or equivalent, air
tank to 175 - 205 kPa (25 - 30 psi). 9. Open the J29532, or equivalent, fluid tank valve to allow
pressurized brake fluid to enter the brake system.
10. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to
ensure that there are no existing external brake fluid
leaks. Any brake fluid leaks identified require repair prior to completing this procedure.
11. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
12. Install a transparent hose over the end of the bleeder valve. 13. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
14. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air
bubbles stop flowing from the bleeder, then
tighten the bleeder valve.
15. With the right rear wheel hydraulic circuit bleeder valve tightened securely - after all air has
been purged from the right rear hydraulic circuitinstall a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
16. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 17. With
the left rear wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the left rear hydraulic circuit- install
a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
18. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 19. With
the right front wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
20. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure > Page 3057
21. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4
wheel hydraulic circuit bleeder valves are properly
tightened.
22. Close the J29532, or equivalent, fluid tank valve, then disconnect the J29532, or equivalent,
from the J35589-A. 23. Remove the J35589-A from the brake master cylinder reservoir. 24. Fill the
brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967
(Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
25. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 26. If the
brake pedal feels spongy perform the following steps:
26.1. Inspect the brake system for external leaks.
26.2. Using a scan tool, perform the antilock brake system automated bleeding procedure to
remove any air that may have been trapped in the BPMV.
27. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
28. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Brake Bleeding > System Information > Service and Repair > ABS
Automated Bleed Procedure > Page 3058
Brake Bleeding: Service and Repair Master Cylinder Bench Bleeding
Master Cylinder Bench Bleeding
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
1. Secure the mounting flange of the brake master cylinder in a bench vise so that the rear of the
primary piston is accessible. 2. Remove the master cylinder reservoir cap and diaphragm. 3. Install
suitable fittings to the master cylinder ports that match the type of flare seat required and also
provide for hose attachment. 4. Install transparent hoses to the fittings installed to the master
cylinder ports, then route the hoses into the master cylinder reservoir. 5. Fill the master cylinder
reservoir to at least the half-way point with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent
DOT-3 brake fluid from a clean, sealed brake fluid container.
6. Ensure that the ends of the transparent hoses running into the master cylinder reservoir are fully
submerged in the brake fluid. 7. Using a smooth, round-ended tool, depress and release the
primary piston as far as it will travel, a depth of about 25 mm (1 inch), several times.
Observe the flow of fluid coming from the ports. As air is bled from the primary and secondary
pistons, the effort required to depress the primary piston will increase and the amount of travel will
decrease.
8. Continue to depress and release the primary piston until fluid flows freely from the ports with no
evidence of air bubbles. 9. Remove the transparent hoses from the master cylinder reservoir.
10. Install the master cylinder reservoir cap and diaphragm. 11. Remove the fittings with the
transparent hoses from the master cylinder ports. Wrap the master cylinder with a clean shop cloth
to prevent brake
fluid spills.
12. Remove the master cylinder from the vise.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Air Bag(s) Arming and Disarming > System Information > Service and
Repair > Disabling
Air Bag(s) Arming and Disarming: Service and Repair Disabling
IMPORTANT: Refer to SIR Service Precautions before disabling the SIR system.
1. Turn the steering wheel until the vehicle's wheels are pointing straight ahead. 2. Turn OFF the
ignition. 3. Remove the key from the ignition.
IMPORTANT: With the AIR BAG Fuse removed and the ignition ON, the AIR BAG indicator
illuminates. This is normal operation and does not indicate an SIR system malfunction.
4. Remove the AIR BAG Fuse from the fuse block. 5. Remove the connector position assurance
(CPA) (1) from the steering wheel module yellow 2-way connector (2) located at the base of the
steering
column.
6. Disconnect the steering wheel module yellow 2-way connector (2) located at the base of the
steering column.
7. Access the IP module yellow 2-way connector (1) located behind the IP module (2) by removing
the upper IP trim panel. Refer to Trim Pad
Replacement - IP Upper in Instrument Panel, Gauges and Warning Indicators.
8. Remove the CPA from the IP module yellow 2-way connector (1) located behind the IP module
(2). 9. Disconnect the IP module yellow 2-way connector (1) located behind the IP module (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Air Bag(s) Arming and Disarming > System Information > Service and
Repair > Disabling > Page 3063
Air Bag(s) Arming and Disarming: Service and Repair Enabling
1. Remove the key from the ignition. 2. Connect the IP module yellow 2-way connector (1) located
behind the main IP support. 3. Install the CPA to the IP module yellow 2-way connector (1) located
behind the main IP support.
4. Connect the steering wheel module yellow 2-way connector (2) located at the base of the
steering column. 5. Install the CPA (1) to the steering wheel module yellow 2-way connector (2)
located at the base of the steering column. 6. Install the AIR BAG Fuse to the fuse block. 7. Staying
well away from all air bags, turn ON the ignition, with the engine OFF.
7.1. The AIR BAG indicator will flash 7 times.
7.2. The AIR BAG indicator will then turn OFF.
8. Perform the Diagnostic System Check - SIR if the AIR BAG indicator does not operate as
described.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Technical
Service Bulletins > Electrical - Aftermarket Fuse Warning
Fuse: Technical Service Bulletins Electrical - Aftermarket Fuse Warning
Bulletin No.: 07-08-45-002
Date: September 05, 2007
ADVANCED SERVICE INFORMATION
Subject: Service Alert: Concerns With Aftermarket Fuses in GM Vehicles
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn) 2008 and
Prior HUMMER H2, H3 2008 and Prior Saab 9-7X
Concerns with Harbor Freight Tools "Storehouse" Branded Blade Type Fuses
General Motors has become aware of a fuse recall by Harbor Freight Tools/Storehouse for a
variety of aftermarket fuses. In two cases, these fuses have not provided protection for the wiring
system of the vehicles they were customer installed in.
Upon testing the 15 amp version, it was found that the fuse still would not "open" when shorted
directly across the battery terminals.
How to Identify These Fuses
Packed in a 120 piece set, the fuse has a translucent, hard plastic, blue body with the amperage
stamped into the top. There are no white painted numbers on the fuse to indicate amperage. There
are no identifying marks on the fuse to tell who is making it. The fuses are known to be distributed
by Harbor Freight Tools but there may be other marketers, and packaging of this style of fuse. It
would be prudent to replace these fuses if found in a customers vehicle. Likewise, if wiring
overheating is found you should check the fuse panel for the presence of this style of fuse.
All GM dealers should use genuine GM fuses on the vehicles they service. You should also
encourage the use of GM fuses to your customers to assure they are getting the required electrical
system protection. GM has no knowledge of any concerns with other aftermarket fuses. If
additional information becomes available, this bulletin will be updated.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View
Fuse: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3071
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3072
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3073
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3074
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3075
Fuse: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3076
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Locations >
Fuse Block - Underhood Connector View > Page 3077
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood
Fuse: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood > Page 3080
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood > Page 3081
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood > Page 3082
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood > Page 3083
Fuse: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse > Component Information > Application
and ID > Fuse Block - Underhood > Page 3084
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3089
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3090
Fuse Block: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3091
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3092
Fuse Block: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3093
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3094
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Locations > Fuse Block - Location > Page 3095
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P
Fuse Block: Diagrams Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3098
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3099
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3100
Fuse Block: Diagrams Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3101
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3102
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3103
Fuse Block: Diagrams Left I/P
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3104
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3105
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3106
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3107
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3108
Fuse Block: Diagrams
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3109
Fuse Block Fuse Applications Part 2
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3110
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3111
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3112
Fuse Application Part 2
Left I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3113
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3114
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3115
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3116
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3117
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Relay Block
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3118
Relay Block - Body - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3119
Relay Block - Body - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3120
Relay Block - Body - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3121
Relay Block - Body - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3122
Relay Block - Body - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3123
Relay Block - Body - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3124
Relay Block - Body - C4
Relay Block - Body - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3125
Relay Block - Body - C6 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3126
Relay Block - Body - C6 Part 2
Relay Block - Body - C8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3127
Relay Block - Body - C9
Relay Block - Body - C10 Part 1
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3128
Relay Block - Body
Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3129
Fuse Block - Right I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3130
Fuse Block - Right I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3131
Fuse Block - Right I/P - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3132
Fuse Block - Right I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3133
Fuse Block - Right I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3134
Fuse Block - Right I/P - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3135
Fuse Block - Right I/P - C6
Fuse Block - Right I/P - C7 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3136
Fuse Block - Right I/P - C7 Part 2
Fuse Block - Right I/P - C8
Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3137
Relay Block - Underhood - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3138
Relay Block - Underhood - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3139
Relay Block - Underhood - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3140
Relay Block - Underhood - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3141
Relay Block - Underhood - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3142
Relay Block - Underhood - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3143
Relay Block - Underhood - C2 Part 4
Relay Block - Underhood - C3 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3144
Relay Block - Underhood - C3 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3145
Relay Block - Underhood - C4 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3146
Relay Block - Underhood - C4 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3147
Relay Block - Underhood - C4 Part 3
Relay Block - Underhood - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3148
Relay Block - Underhood - C6
Relay Block - Underhood - C7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Diagrams > Fuse Block - Left I/P > Page 3149
Relay Block - Underhood - C8
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P
Fuse Block: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P > Page 3152
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P > Page 3153
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P > Page 3154
Fuse Block: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P > Page 3155
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Application and ID > Fuse Block - Left I/P > Page 3156
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement
Fuse Block: Service and Repair Underhood Electrical Center or Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Remove the left fender upper brace.
3. Remove the electrical center brace cover assemble by lifting the cover (3) outwards to clear the
tabs. 4. Remove all fuses and relays.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3159
5. Push on the tab (3) so that the electrical center can be rotated on the studs located at (2). 6.
Remove all connectors by removing the bolt (1) for each connector. 7. Disconnect all connectors
from the electrical center block.
8. Push on the tabs (2) in order to lift the electrical center (1) out of the housing.
9. To replace the starting and charging center bracket remove the 4 retaining bolts (1).
10. Remove the starting and charging center bracket assembly from the fender.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3160
INSTALLATION PROCEDURE
1. Install the starting and charging center bracket assembly to the front fender.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the 4 retaining bolts (1).
Tighten Tighten the 4 retaining bolts (1) to 9 N.m (80 lb in).
3. Align the electrical center block (1) stubs in the slots so that the tabs (2) retains it in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3161
4. Connect the wire connectors to the lower portion of the electrical center block. 5. Connect the
wire connectors with the bolts to the electrical center block.
Tighten Tighten all connector bolts (1) to 9 N.m (80 lb in).
6. Ensure all wire connectors are securely connected. 7. Set the electrical center block in its resting
position till the tabs (3) locks in place.
8. Install the lower part of the cover (1). 9. With the cover (2) off, use the fuse location information
to install all fuses and relays.
10. Install the cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3162
11. Install the fender upper brace. 12. Install the 4 fender upper brace bolts.
Tighten Tighten the 4 retaining bolts to 25 N.m (18 lb ft).
13. Connect the negative battery cable. 14. Start vehicle and ensure all components function
properly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3163
Fuse Block: Service and Repair I/P Electrical Center or Junction Block Replacement
Left
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the left side end panel. 3. Press on the
clips on the top and the bottom in order to remove the fuse block from the instrument panel (IP)
assembly. 4. Disconnect all wiring connectors from the fuse block. 5. Remove the fuse block from
the vehicle.
INSTALLATION PROCEDURE
1. Connect all wiring connectors to the fuse block. 2. Position the fuse block onto the IP assembly.
3. Press on the clips on the top and the bottom of the fuse block and push in the clips until seated.
4. Install the left side end panel. 5. Connect the negative battery cable(s).
Right
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3164
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the right side end panel. 3. Unclip the
wiring connector(s) from the front of the Instrument Panel (IP) wiring harness junction block Unclip
the harness from the fastener. 4. Remove the IP wiring harness junction block from the IP by
pressing on both of the clips and pulling rearward. 5. Disconnect the lower IP light bulb by twisting
the bulb counterclockwise and pulling the bulb rearward. 6. Feed the IP wiring harness junction
block through the hole in the IP. 7. Disconnect all remaining wiring connectors from the rear of the
IP wiring harness junction block. 8. Remove the IP wiring harness junction block from the vehicle.
INSTALLATION PROCEDURE
1. Connect the wiring connectors to the rear of the IP wiring harness junction block. 2. Feed the IP
wiring harness junction block through the hole in the IP. 3. Connect the lower IP light bulb by
twisting the bulb socket clockwise while pushing in. 4. Connect the IP wiring harness junction block
to the IP by pressing on both clips and pushing until sealed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3165
5. Connect the wiring connector(s) onto the front of the IP wiring harness junction block and
connect the harness to the fastener. 6. Install the right side end panel. 7. Connect the negative
battery cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3166
Fuse Block: Service and Repair Body Wiring Harness Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the harness from the front of the body
wiring harness junction block. 3. Unsnap the cover from the body wiring harness junction block.
4. Unsnap the top pivots and rotate the body wiring harness junction block (1) down. Unsnap the
lower pivots and remove the body wiring harness
junction block from the bracket (2).
5. Disconnect the two 68-way IP connectors. 6. Disconnect the remaining wiring connectors from
the body wiring harness junction block. 7. Remove the body wiring harness junction block from the
vehicle.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Fuse Block > Component Information >
Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 3167
1. Connect the two 68-way IP connectors to the body wiring harness junction block. 2. Connect all
remaining wiring connectors. 3. Snap the body wiring harness junction block (1) onto the bracket
(2). 4. Connect the harness to the front of the body wiring harness junction block.
5. Fasten the cover to the body wiring harness junction block. 6. Connect the negative battery
cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Locations > Page 3171
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Locations > Page 3172
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Locations > Page 3173
Junction Block - Rear Lamps - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Service and Repair > Relay Replacement (Within an Electrical Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Service and Repair > Relay Replacement (Within an Electrical Center) > Page 3176
1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Fuses and Circuit Breakers > Relay Box > Component Information >
Service and Repair > Relay Replacement (Within an Electrical Center) > Page 3177
Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Service Reminder Indicators > Malfunction Indicator Lamp > Component
Information > Testing and Inspection > Malfunction Indicator Lamp (MIL) Always On
Malfunction Indicator Lamp: Testing and Inspection Malfunction Indicator Lamp (MIL) Always On
CIRCUIT DESCRIPTION
Battery positive voltage is supplied directly to the malfunction indicator lamp (MIL). The powertrain
control module (PCM) turns the MIL ON by grounding the MIL control circuit.
MIL OPERATION
The MIL is located on the instrument panel (IP).
MIL FUNCTION
^ The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for
service as soon as possible.
^ The MIL illuminates during a bulb test and a system test.
^ A DTC will be stored if a MIL is requested by the diagnostic.
MIL ILLUMINATION
^ The MIL will illuminate with ignition switch ON and the engine not running.
^ The MIL will turn OFF when the engine is started.
^ The MIL will remain ON if the self-diagnostic system has detected a malfunction.
^ The MIL may turn OFF if the malfunction is not present.
^ If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so long as the
ignition switch is ON.
^ If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition
switch is cycled OFF, then ON.
DIAGNOSTIC AIDS
If the problem is intermittent, refer to Intermittent Conditions. See: Powertrain
Management/Computers and Control Systems/Testing and Inspection/Initial Inspection and
Diagnostic Overview/Intermittent Conditions
TEST DESCRIPTION
Steps 1-6
The number below refers to the step numbers on the diagnostic table. 2. The step determines if the
condition is with the MIL control circuit or the PCM.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Service Reminder Indicators > Malfunction Indicator Lamp > Component
Information > Testing and Inspection > Malfunction Indicator Lamp (MIL) Always On > Page 3183
Malfunction Indicator Lamp: Testing and Inspection Malfunction Indicator Lamp (MIL) Inoperative
CIRCUIT DESCRIPTION
Battery positive voltage is supplied directly to the malfunction indicator lamp (MIL). The powertrain
control module (PCM) turns the MIL ON by grounding the MIL control circuit. There should be a
steady MIL with the ignition ON and the engine OFF.
MIL OPERATION
The MIL is located on the instrument panel (IP).
MIL FUNCTION
^ The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for
service as soon as possible.
^ The MIL illuminates during a bulb test and a system test.
^ A DTC will be stored if a MIL is requested by the diagnostic.
MIL ILLUMINATION
^ The MIL will illuminate with ignition switch ON and the engine not running.
^ The MIL will turn OFF when the engine is started.
^ The MIL will remain ON if the self-diagnostic system has detected a malfunction.
^ The MIL may turn OFF if the malfunction is not present.
^ If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so long as the
ignition switch is ON.
^ If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition
switch is cycled OFF, then ON.
DIAGNOSTIC AIDS
If the problem is intermittent, refer to Intermittent Conditions. See: Powertrain
Management/Computers and Control Systems/Testing and Inspection/Initial Inspection and
Diagnostic Overview/Intermittent Conditions
TEST DESCRIPTION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Service Reminder Indicators > Malfunction Indicator Lamp > Component
Information > Testing and Inspection > Malfunction Indicator Lamp (MIL) Always On > Page 3184
Steps 1-14
The numbers below refer to the step numbers on the diagnostic table. 3. This step determines if the
condition is with the MIL control circuit or the PCM. 4. This step determines if a voltage is being
applied to the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Service Reminder Indicators > Oil Change Reminder Lamp > Component
Information > Service and Repair
Oil Change Reminder Lamp: Service and Repair
How to Reset the CHANGE ENGINE OIL Message
The GM "Oil Life System" calculates when to change your engine oil and filter based on vehicle
use. Anytime your oil is changed, reset the system so it can calculate when the next oil change is
required. If a situation occurs where you change oil prior to a CHANGE ENGINE OIL message
being turned on, reset the system.
To reset the CHANGE ENGINE OIL message do the following:
1. Turn the ignition key to the RUN with the engine off.
2. Fully press and release the accelerator pedal three times within five seconds.
If the CHANGE ENGINE OIL message flashes for 5 seconds, the system is reset.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Relays and Modules - Wheels and Tires > Tire Pressure
Monitor Receiver / Transponder > Component Information > Technical Service Bulletins > Tire Monitor System - TPM
Sensor Information
Tire Pressure Monitor Receiver / Transponder: Technical Service Bulletins Tire Monitor System TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Sensors and Switches - Wheels and Tires > Tire
Pressure Sensor > Component Information > Technical Service Bulletins > Tire Monitor System - TPM Sensor Information
Tire Pressure Sensor: Technical Service Bulletins Tire Monitor System - TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Tire Monitoring System > Tire Pressure Monitor
Receiver / Transponder > Component Information > Technical Service Bulletins > Tire Monitor System - TPM Sensor
Information
Tire Pressure Monitor Receiver / Transponder: Technical Service Bulletins Tire Monitor System TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Tire Monitoring System > Tire Pressure Sensor >
Component Information > Technical Service Bulletins > Tire Monitor System - TPM Sensor Information
Tire Pressure Sensor: Technical Service Bulletins Tire Monitor System - TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Tires > Spare Tire > Component Information >
Technical Service Bulletins > Tire/Wheel - Spare Tire Is Non-Matching To Other Tires
Spare Tire: Technical Service Bulletins Tire/Wheel - Spare Tire Is Non-Matching To Other Tires
INFORMATION
Bulletin No.: 02-03-10-001E
Date: November 01, 2010
Subject: Spare Tire is a Different Size than Other Tires
Models:
2002-2011 Cadillac Escalade Models 1999-2007 Chevrolet Silverado (Classic) 2000-2011
Chevrolet Suburban, Tahoe 2002-2011 Chevrolet Avalanche 1999-2007 GMC Sierra (Classic)
2001 GMC Sierra C3 2001-2011 GMC Yukon Models 2002-2011 GMC Sierra Denali
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 02-03-10-001D (Section 03 - Suspension).
This bulletin is being issued to supply additional information concerning the spare tire on the above
vehicles. You or your customers may have noticed that the spare tire has a 16-inch diameter steel
wheel or 17-inch diameter aluminum wheel while the road tires have a 17-inch, 18-inch, 20-inch or
22-inch diameter aluminum wheel. Although the spare tire has a different wheel diameter and may
be a different brand, the rolling circumference is nearly identical to the road tires. The size
difference will not cause a concern because the spare and the other tires will travel the same
distance in one revolution.
This combination of non-matching tires is used most often on full-size trucks. These vehicles use a
road tire and wheel combination that may be too large to conveniently fit the storage compartment
space of the vehicle. The customer may not be able to easily remove the spare tire/wheel from the
storage area because of its size and/or weight. A steel spare wheel, rather than an aluminum one,
may be used since the spare is stowed under the vehicle where it is exposed to road and weather
elements. A steel wheel is less likely to incur cosmetic damage while in the stowed position for long
periods of time.
Please provide this information to your customers. Also, remind your customers of the importance
of following the tire maintenance schedule as listed in their Owner Manual. Additional tire care
information can be found by visiting www.gmtiresafety.com or contacting GM toll-free.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV)
Wheels: Customer Interest Wheels/Tires - Tire Radial Force Variation (RFV)
INFORMATION
Bulletin No.: 00-03-10-006F
Date: May 04, 2010
Subject: Information on Tire Radial Force Variation (RFV)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks 2010 and Prior HUMMER H2, H3 2009
and Prior Saab 9-7X 2000-2005 Saturn L Series 2003-2007 Saturn ION
Supercede: This bulletin is being revised to considerably expand the available information on
Radial Force Variation (RFV) and should be reviewed in whole. Please discard Corporate Bulletin
Number 00-03-10-006E (Section 03 - Suspension).
Important
- Before measuring tires on equipment such as the Hunter GSP9700, the vehicle MUST be driven
a minimum of 16 km (10 mi) to ensure removal of any flat-spotting. Refer to Corporate Bulletin
Number 03-03-10-007E - Tire/Wheel Characteristics of GM Original Equipment Tires.
- Equipment such as the Hunter GSP9700 MUST be calibrated prior to measuring tire/wheel
assemblies for each vehicle.
The purpose of this bulletin is to provide guidance to GM dealers when using tire force variation
measurement equipment, such as the Hunter GSP9700. This type of equipment can be a valuable
tool in diagnosing vehicle ride concerns. The most common ride concern involving tire radial force
variation is highway speed shake on smooth roads.
Tire related smooth road highway speed shake can be caused by three conditions: imbalance, out
of round and tire force variation. These three conditions are not necessarily related. All three
conditions must be addressed.
Imbalance is normally addressed first, because it is the simpler of the three to correct. Off-vehicle,
two plane dynamic wheel balancers are readily available and can accurately correct any
imbalance. Balancer calibration and maintenance, proper attachment of the wheel to the balancer,
and proper balance weights, are all factors required for a quality balance. However, a perfectly
balanced tire/wheel assembly can still be "oval shaped" and cause a vibration.
Before balancing, perform the following procedures.
Tire and Wheel Diagnosis
1. Set the tire pressure to the placard values. 2. With the vehicle raised, ensure the wheels are
centered on the hub by loosening all wheel nuts and hand-tightening all nuts first by hand while
shaking the wheel, then torque to specifications using a torque wrench, NOT a torque stick.
3. Visually inspect the tires and the wheels. Inspect for evidence of the following conditions and
correct as necessary:
- Missing balance weights
- Bent rim flange
- Irregular tire wear
- Incomplete bead seating
- Tire irregularities (including pressure settings)
- Mud/ice build-up in wheel
- Stones in the tire tread
- Remove any aftermarket wheels and/or tires and restore vehicle to original condition prior to
diagnosing a smooth road shake condition.
4. Road test the vehicle using the Electronic Vibration Analyzer (EVA) essential tool. Drive for a
sufficient distance on a known, smooth road
surface to duplicate the condition. Determine if the vehicle is sensitive to brake apply. If the brakes
are applied lightly and the pulsation felt in the steering wheel increases, refer to the Brakes section
of the service manual that deals with brake-induced pulsation. If you can start to hear the vibration
as a low boom noise (in addition to feeling it), but cannot see it, the vehicle likely has a first order
(one pulse per propshaft revolution) driveline vibration. Driveline first order vibrations are high
enough in frequency that most humans can start to hear them at highway speeds, but are too high
to be able to be easily seen. These issues can be caused by driveline imbalance or misalignment.
If the vehicle exhibits this low boom and the booming pulses in-and-out on a regular basis (like a
throbbing), chances are good that the vehicle could have driveline vibration. This type
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3221
of vibration is normally felt more in the "seat of the pants" than the steering wheel.
5. Next, record the Hertz (Hz) reading as displayed by the EVA onto the tire data worksheet found
at the end of this bulletin. This should be done
after a tire break-in period of at least 16 km (10 mi) at 72 km/h (45 mph) or greater, in order to
eliminate any possible tire flat-spotting. This reading confirms what the vehicle vibration frequency
is prior to vehicle service and documents the amount of improvement occurring as the result of the
various steps taken to repair. Completing the Steering Wheel Shake Worksheet below is required.
A copy of the completed worksheet must be saved with the R.O. and a copy included with any
parts returned to the Warranty Parts Center for analysis. A reading of 35 to 50 Hz typically
indicates a first order propshaft vibration. If this is the situation, refer to Corporate Bulletin Number
08-07-30-044D. Generally, a reading between 10 and 20 Hz indicates a tire/wheel vibration and if
this is the reading obtained, continue using this bulletin. If the tire 1st order vibration goes away
and stays away during this evaluation, the cause is likely tire flat-spotting. Tire flat-spotting vibration
may come and go at any speed over 72 km/h (45 mph) during the first 10 minutes of operation, if
vibration continues after 10 minutes of driving at speeds greater than 72 km/h (45 mph), tire
flat-spotting can be ruled out as the cause for vibration.
6. If flat-spotting is the cause, provide the explanation that this has occurred due to the vehicle
being parked for long periods of time and that the
nature of the tire is to take a set. Refer to Corporate Bulletin Number 03-03-10-007E: Information
on Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment
Tires.
7. If the road test indicates a shake/vibration exists, check the imbalance of each tire/wheel
assembly on a known, calibrated, off-car dynamic
balancer.Make sure the mounting surface of the wheel and the surface of the balancer are
absolutely clean and free of debris. Be sure to chose the proper cone/collet for the wheel, and
always use the pilot bore for centering. Never center the wheel using the hub-cap bore since it is
not a precision machined surface. If any assembly calls for more than 1/4 ounce on either rim
flange, remove all balance weights and rebalance to as close to zero as possible. If you can see
the vibration (along with feeling it) in the steering wheel (driving straight without your hands on the
wheel), it is very likely to be a tire/wheel first order (one pulse per revolution) disturbance. First
order disturbances can be caused by imbalance as well as non-uniformities in tires, wheels or
hubs. This first order frequency is too low for a human to hear, but if the amplitude is high enough,
it can be seen.
If a vibration or shake still exists after balancing, any out of round conditions, of the wheel, and
force variation conditions of the tire, must be addressed. Equipment such as the Hunter GSP9700
can address both (it is also a wheel balancer).
Tire radial force vibration (RFV) can be defined as the amount of stiffness variation the tire will
produce in one revolution under a constant load. Radial force variation is what the vehicle feels
because the load (weight) of the vehicle is always on the tires. Although free runout of tires (not
under load) is not always a good indicator of a smooth ride, it is critical that total tire/wheel
assembly runout be within specification.
Equipment such as the Hunter GSP9700 loads the tire, similar to on the vehicle, and measures
radial force variation of the tire/wheel assembly. Note that the wheel is affecting the tire's RFV
measurement at this point. To isolate the wheel, its runout must be measured. This can be easily
done on the Hunter, without the need to set up dial indicators. If the wheel meets the runout
specification, the tire's RFV can then be addressed.
After measuring the tire/wheel assembly under load, and the wheel alone, the machine then
calculates (predicts) the radial force variation of the tire. However, because this is a prediction that
can include mounting inaccuracies, and the load wheel is much smaller in diameter than used in
tire production, this type of service equipment should NOT be used to audit new tires. Rather, it
should be used as a service diagnostic tool to minimize radial force variation of the tire/wheel
assembly.
Equipment such as the Hunter GSP9700 does an excellent job of measuring wheel runout, and of
finding the low point of the wheel (for runout) and the high point of the tire (for radial force
variation). This allows the tire to be matched mounted to the wheel for lowest tire/wheel assembly
force variation.
The machine will simplify this process into easy steps. The following assembly radial force variation
numbers should be used as a guide:
When measuring RFV and match mounting tires perform the following steps.
Measuring Wheel Runout and Assembly Radial Force Variation
Important The completed worksheet at the end of this bulletin must be attached to the hard copy of
the repair order.
- Measure radial force variation and radial runout.
- If a road force/balancing machine is used, record the radial force variation (RFV) on the
worksheet at the end of this bulletin. It may be of benefit to have the lowest RFV assembly to the
front left corner. If the machine is not available and the EVA data suggests there is an issue, swap
the tire and wheel assemblies from the front to the back. Re-check on the EVA and if the problem
still exists, test another vehicle to find tires that do not exhibit the same frequency and swap those
tires onto the subject vehicle.
- If a runout/balancing machine is used, record the radial runout of the tire/wheel assemblies on the
worksheet at the end of this bulletin. If one or more of the tire/wheel assemblies are more than.040
in (1.02 mm), match mount the tire to the wheel to get below.040 in (1.02 mm). For sensitive
customers, readings of 0.030 inch (0.76 mm) or less are preferable, it may also be of benefit to
have the lowest runout assembly to the front left corner. If the machine is not available and the
EVA data suggests there is an issue, swap the tire and wheel assemblies from the front to the
back. Re-check on the EVA and if the problem still exists, test another vehicle to find tires that do
not exhibit the same frequency and swap those tires
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3222
onto the subject vehicle.
- After match mounting, the tire/wheel assembly must be rebalanced.
If match mounting tires to in-spec wheels produces assembly values higher than these, tire
replacement may be necessary. Replacing tires at lower values will probably mean good tires are
being condemned. Because tires can sometimes become temporarily flat-spotted, which will affect
force variation, it is important that the vehicle be driven at least 16 km (10 mi) prior to measuring.
Tire pressure must also be adjusted to the usage pressure on the vehicle's tire placard prior to
measuring.
Most GM vehicles will tolerate radial force variation up to these levels. However, some vehicles are
more sensitive, and may require lower levels. Also, there are other tire parameters that equipment
such as the Hunter GSP9700 cannot measure that may be a factor. In such cases, TAC should be
contacted for further instructions.
Important
- When mounting a GM wheel to a wheel balancer/force variation machine, always use the wheel's
center pilot hole. This is the primary centering mechanism on all GM wheels; the bolt holes are
secondary. Usually a back cone method to the machine should be used. For added accuracy and
repeatability, a flange plate should be used to clamp the wheel onto the cone and machine. This
system is offered by all balancer manufacturers in GM's dealer program.
- Any type of service equipment that removes tread rubber by grinding, buffing or truing is NOT
recommended, and may void the tire warranty. However, tires may have been ground by the tire
company as part of their tire manufacturing process. This is a legitimate procedure.
Steering Wheel Shake Worksheet
When diagnosing vibration concerns, use the following worksheet in conjunction with the
appropriate Vibration Analysis-Road testing procedure in the Vibration Correction sub-section in SI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3223
Refer to the appropriate section of SI for specifications and repair procedures that are related to the
vibration concern.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels
Wheels: Customer Interest Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels
TECHNICAL
Bulletin No.: 05-03-10-003F
Date: April 27, 2010
Subject: Low Tire Pressure, Leaking Cast Aluminum Wheels (Repair with Adhesive Sealant)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks (Including Saturn) 2010 and Prior
HUMMER H2, H3 2009 and Prior Saab 9-7X with Cast Aluminum Wheels
Supercede: This bulletin is being revised to update the model years and the bulletin reference
information. Please discard Corporate Bulletin Number 05-03-10-003E (Section 03 - Suspension).
Condition
Some customers may comment on a low tire pressure condition.
Diagnosis of the low tire pressure condition indicates an air leak through the cast aluminum wheel.
Cause
Porosity in the cast aluminum wheel may be the cause.
Notice
This bulletin specifically addresses issues related to the wheel casting that may result in an air
leak. For issues related to corrosion of the wheel in service, please refer to Corporate Bulletin
Number 08-03-10-006C - Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light
Illuminated, Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat).
Correction
1. Remove the tire and wheel assembly from the vehicle. Refer to the appropriate service
procedure in SI. 2. Locate the leaking area by inflating the tire to 276 kPa (40 psi) and dipping the
tire/wheel assembly in a water bath, or use a spray bottle with soap
and water to locate the specific leak location.
Important
- If the porosity leak is located in the bead area of the aluminum rim (where the tire meets the rim),
the wheel should be replaced.
- If two or more leaks are located on one wheel, the wheel should be replaced.
3. If air bubbles are observed, mark the location.
- If the leak location is on the tire/rubber area, refer to Corporate Bulletin Number 04-03-10-001F Tire Puncture Repair Procedures for All Cars and Light Duty Trucks.
- If the leak is located on the aluminum wheel area, continue with the next step.
4. Inscribe a mark on the tire at the valve stem in order to indicate the orientation of the tire to the
wheel. 5. Dismount the tire from the wheel. Refer to Tire Mounting and Dismounting. 6. Remove
the tire pressure sensor. Refer to Tire Pressure Sensor removal procedure in SI. 7. Scuff the
INSIDE rim surface at the leak area with #80 grit paper and clean the area with general purpose
cleaner, such as 3M(R) General Purpose
Adhesive Cleaner, P/N 08984, or equivalent.
8. Apply a 3 mm (0.12 in) thick layer of Silicone - Adhesive/Sealant, P/N 12378478 (in Canada, use
88900041), or equivalent, to the leak area. 9. Allow for the adhesive/sealant to dry.
Notice Caution must be used when mounting the tire so as not to damage the sealer. Damaging
the repair area may result in an air leak.
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels >
Page 3228
10. Align the inscribed mark on the tire with the valve stem on the wheel. 11. Reinstall the Tire
Pressure Sensor. Refer to Tire Pressure Sensor installation procedure in SI. 12. Mount the tire on
the wheel. Refer to Tire Mounting and Dismounting. 13. Pressurize the tire to 276 kPa (40 psi) and
inspect for leaks. 14. Adjust tire pressure to meet the placard specification. 15. Balance the
tire/wheel assembly. Refer to Tire and Wheel Assembly Balancing - Off-Vehicle. 16. Install the tire
and wheel assembly onto the vehicle. Refer to the appropriate service procedure in SI.
Parts Information
Warranty Information (excluding Saab U.S. Models)
Important The Silicone - Adhesive/Sealant comes in a case quantity of six. ONLY charge warranty
one tube of adhesive/sealant per wheel repair.
For vehicles repaired under warranty, use:
One leak repair per wheel.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON
Wheels: Customer Interest Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON
TECHNICAL
Bulletin No.: 08-03-10-006C
Date: April 27, 2010
Subject: Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light Illuminated,
Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat)
Models:
2000-2011 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009 HUMMER H2
2006-2010 HUMMER H3 2005-2009 Saab 9-7X
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 08-03-10-006B (Section 03 - Suspension).
Condition
Some customers may comment on a tire that slowly loses air pressure over a period of days or
weeks.
Cause
Abrasive elements in the environment may intrude between the tire and wheel at the bead seat.
There is always some relative motion between the tire and wheel (when the vehicle is driven) and
this motion may cause the abrasive particles to wear the wheel and tire materials. As the wear
continues, there may also be intrusion at the tire/wheel interface by corrosive media from the
environment. Eventually a path for air develops and a 'slow' leak may ensue. This corrosion may
appear on the inboard or outboard bead seating surface of the wheel. This corrosion will not be
visible until the tire is dismounted from the wheel.
Notice
This bulletin specifically addresses issues related to wheel bead seat corrosion that may result in
an air leak. For issues related to porosity of the wheel casting that may result in an air leak, please
refer to Corporate Bulletin Number 05-03-10-006F - Low Tire Pressure, Leaking Cast Aluminum
Wheels (Repair with Adhesive Sealant)
Correction
In most cases, this type of air loss can be corrected by following the procedure below.
Important DO NOT replace a wheel for slow air loss unless you have evaluated and/or tried to
repair the wheel with the procedure below.
Notice
The repair is no longer advised or applicable for chromed aluminum wheels.
1. Remove the wheel and tire assembly for diagnosis. Refer to Tire and Wheel Removal and
Installation in SI. 2. After a water dunk tank leak test, if you determine the source of the air leak to
be around the bead seat of the wheel, dismount the tire to examine
the bead seat. Shown below is a typical area of bead seat corrosion.Typical Location of Bead Seat
Corrosion
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON >
Page 3233
Important Other forms of slow air leaks are possible. If the body of the tire, valve stem and wheel
flange show no signs of air seepage, refer to Corporate Bulletin Number 05-03-10-003D for
additional information on possible wheel porosity issues.
3. Bead seat corrosion is identified by what appears like blistering of the wheel finish, causing a
rough or uneven surface that is difficult for the tire to
maintain a proper seal on. Below is a close-up photo of bead seat corrosion on an aluminum wheel
that was sufficient to cause slow air loss. Close-Up of Bead Seat Corrosion
4. If corrosion is found on the wheel bead seat, measure the affected area as shown below.
- For vehicles with 32,186 km (20,000 mi) or less, the total allowable combined linear area of
repairable corrosion is 100 mm (4 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
- For vehicles that have exceeded 32,186 km (20,000 mi), the total allowable combined linear area
of repairable corrosion is 200 mm (8 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
5. In order to correct the wheel leak, use a clean-up (fine cut) sanding disc or biscuit to remove the
corrosion and any flaking paint. You should
remove the corrosion back far enough until you reach material that is stable and firmly bonded to
the wheel. Try to taper the edge of any flaking paint as best you can in order to avoid sharp edges
that may increase the chance of a leak reoccurring. The photo below shows an acceptable repaired
surface.
Notice Corrosion that extends up the lip of the wheel, where after the clean-up process it would be
visible with the tire mounted, is only acceptable on the inboard flange. The inboard flange is not
visible with the wheel assembly in the mounted position. If any loose coatings or corrosion extend
to the visible surfaces on the FACE of the wheel, that wheel must be replaced.
Important Remove ONLY the material required to eliminate the corrosion from the bead seating
surface. DO NOT remove excessive amounts of material. ALWAYS keep the sealing surface as
smooth and level as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON >
Page 3234
Acceptably Prepared (Cleaned-Up) Wheel Surface
6. Once the corrosion has been eliminated, you should coat the repaired area with a commercially
available tire sealant such as Patch Brand Bead
Sealant or equivalent. Commercially available bead sealants are black rubber-like coatings that will
permanently fill and seal the resurfaced bead seat. At 21°C (70°F) ambient temperature, this
sealant will set-up sufficiently for tire mounting in about 10 minutes.Coated and Sealed Bead Seat
7. Remount the tire and install the repaired wheel and tire assembly. Refer to Tire and Wheel
Removal and Installation in SI.
Parts Information
Patch Brand Bead Sealer is available from Myers Tires at 1-800-998-9897 or on the web at
www.myerstiresupply.com. The one-quart size can of sealer will repair about 20 wheels.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON >
Page 3235
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire Leak/Vibration
Wheels: Customer Interest Wheels/Tires - Slow Tire Leak/Vibration
Bulletin No.: 03-03-10-001D
Date: January 17, 2008
TECHNICAL
Subject: Tire Slowly Goes Flat and/or Excessive wheel Vibration Caused By Bead Splits (Replace
wheels with New Heavy Duty Rim Version)
Models: 1999-2006 Chevrolet Silverado 1500 Series Pickup Models (Classic) 1999-2006 Chevrolet
Express 1500 Series Vans 2000-2006 Chevrolet Suburban Tahoe 1999-2006 GMC Sierra 1500
Series Pickup Models (Classic) 1999-2006 GMC Savana 1500 Series Vans 2002-2006 GMC
Yukon Yukon XL 2007 GMC Sierra Denali Crew Cab
with 6-Bolt, 16 X 6.5 Full Face Steel wheel (Base and RPO PY2)
Supercede:
This bulletin is being revised to add the Express and Savana models and add information to the
Correction section. Please discard Corporate Bulletin Number 03-03-10-001C (Section 03 Suspension).
Implementation of this service bulletin by "GM of Canada" dealers requires prior District Service
Manager approval.
Condition
Some customers may comment on a tire that slowly goes flat and/or excessive wheel vibration.
This condition is more apparent on vehicles in which customer usage typically involves frequent
severe conditions such as:
High load (at or above gross vehicle weight)
Rough road/off road usage
Fleet/Commercial usage
Cause
The wheel may experience a crack or split in the outboard bead seat weld area. A weld attaches
the rim and disc together on full-face wheels in this area. To identify this wheel it is offered in a
silver painted version P/N 9593915 code "TZA" and a chrome-clad version, P/N 9593150 code
"RSC" (these codes are stamped into the wheel's disc near the bolt holes).
Correction
Wheel replacement should only be done for air loss and/or vibration caused by bead splits.
A new heavy-duty rim version of these wheels has been released for service. The new heavy-duty
painted wheel is P/N 9595245 code "FFU" used as a road wheel and spare. The new heavy-duty
chrome clad version is P/N 9595306 code "FFW" used as a road wheel only (these codes are
stamped into the inboard rim flange balance weight area and are also on a sticker near the bolt
holes). If a condition of a crack or split as described above occurs all (5) five of the original wheels
on the vehicle should be replaced with the new heavy-duty wheels as follows: Replace road wheel
P/N 9593915 with P/N 9595245. Replace road wheel PIN 9593150 with P/N 9595306. Replace the
spare wheel with P/N 9595245 on all vehicles.
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Customer Interest: > 03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire Leak/Vibration > Page 3240
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Staining/Pitting/Corrosion
INFORMATION
Bulletin No.: 00-03-10-002F
Date: April 21, 2011
Subject: Chemical Staining, Pitting, Corrosion and/or Spotted Appearance of Chromed Aluminum
Wheels
Models:
2012 and Prior GM Cars and Trucks
Supercede: This bulletin is being revised to update model years, suggest additional restorative
products and add additional corrosion information. Please discard Corporate Bulletin Number
00-03-10-002E (Section 03 - Suspension). Important You may give a copy of this bulletin to the
customer.
What is Chemical Staining of Chrome Wheels? Figure 1
Chemical staining in most cases results from acid based cleaners (refer to Figure 1 for an
example). These stains are frequently milky, black, or greenish in appearance. They result from
using cleaning solutions that contain acids on chrome wheels. Soap and water is usually sufficient
to clean wheels.
If the customer insists on using a wheel cleaner they should only use one that specifically states
that it is safe for chromed wheels and does not contain anything in the following list. (Dealers
should also survey any products they use during prep or normal cleaning of stock units for these
chemicals.)
- Ammonium Bifluoride (fluoride source for dissolution of chrome)
- Hydrofluoric Acid (directly dissolves chrome)
- Hydrochloric Acid (directly dissolves chrome)
- Sodium Dodecylbenzenesulfonic Acid
- Sulfamic Acid
- Phosphoric Acid
- Hydroxyacetic Acid
Notice
Many wheel cleaner instructions advise to take care to avoid contact with painted surfaces. Most
customers think of painted surfaces as the fenders, quarter panels and other exterior sheet metal.
Many vehicles have painted brake calipers. Acidic wheel cleaners may craze, crack, or discolor the
paint on the brake calipers. Damage from wheel cleaners is not covered under the vehicle new car
warranty. Soap and water applied with a soft brush is usually all that is required to clean the
calipers.
Whenever any wheel cleaner is used, it must be THOROUGHLY rinsed off of the wheel with clean,
clear water. Special care must be taken to rinse under the hub cap, balance weights, wheel nuts,
lug nut caps, between the wheel cladding and off the back side of the wheel. Wheels returned to
the Warranty Parts Center (WPC) that exhibit damage from wheel cleaners most often have the
damage around and under the wheel weight where the cleaner was incompletely flushed away.
Notice
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3246
Do not use cleaning solutions that contain hydrofluoric, oxalic and most other acids on chrome
wheels (or any wheels).
If the customer is unsure of the chemical make-up of a particular wheel cleaner, it should be
avoided.
For wheels showing signs of milky staining from acidic cleaners, refer to Customer Assistance and
Instructions below.
Warranty of Stained Chrome Wheels
Stained wheels are not warrantable. Most acid based cleaners will permanently stain chrome
wheels. Follow-up with dealers has confirmed that such cleaners were used on wheels that were
returned to the Warranty Parts Center (WPC). Any stained wheels received by the WPC will be
charged back to the dealership. To assist the customer, refer to Customer Assistance and
Instructions below.
Pitting or Spotted Appearance of Chrome Wheels Figure 2
A second type or staining or finish disturbance may result from road chemicals, such as calcium
chloride used for dust control of unpaved roads. The staining will look like small pitting (refer to
Figure 2). This staining will usually be on the leading edges of each wheel spoke, but may be
uniformly distributed. If a vehicle must be operated under such conditions, the chrome wheels
should be washed with mild soap and water and thoroughly rinsed as soon as conveniently
possible.
Important Road chemicals, such as calcium chloride used for dust control of unpaved roads, can
also stain chrome wheels. The staining will look like small pitting. This staining will usually be on
the leading edges of each wheel spoke. This is explained by the vehicle traveling in the forward
direction while being splashed by the road chemical. If a vehicle must be operated under such
conditions, the chrome wheels should be washed with mild soap and water and thoroughly rinsed
as soon as conveniently possible.
Warranty of Pitted or Spotted Chrome Wheels
Wheels returned with pitting or spotting as a result of road chemicals may be replaced one time.
Damage resulting from contact with these applied road chemicals is corrosive to the wheels finish
and may cause damage if the wheels are not kept clean.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean if they are operating the vehicle in an area that
applies calcium chloride or other dust controlling chemicals! "GM of Canada" dealers require prior
approval by the District Manager - Customer Care and Service Process (DM-CCSP).
"Stardust" Corrosion of Chrome Wheels Figure 3
A third type of finish disturbance results from prolonged exposure to brake dust and resultant
penetration of brake dust through the chrome. As brakes are applied hot particles of brake material
are thrown off and tend to be forced through the leading edge of the wheel spoke windows by
airflow. These
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3247
hot particles embed themselves in the chrome layer and create a small pit. If the material is allowed
to sit on the wheel while it is exposed to moisture or salt, it will corrode the wheel beneath the
chrome leaving a pit or small blister in the chrome.
Heavy brake dust build-up should be removed from wheels by using GM Chrome Cleaner and
Polish, P/N 1050173 (in Canada use 10953013). For moderate cleaning, light brake dust build-up
or water spots use GM Swirl Remover Polish, P/N 12377965 (in Canada, use Meguiars
Plast-X(TM) Clear Plastic Cleaner and Polish #G12310C**). After cleaning, the wheel should be
waxed using GM Cleaner Wax, P/N 12377966 (in Canada, use Meguiars Cleaner Wax
#M0616C**), which will help protect the wheel from brake dust and reduce adhesion of any brake
dust that gets on the wheel surface. For general maintenance cleaning, PEEK Metal Polish† may
be used. It will clean and shine the chrome and leave behind a wax coating that may help protect
the finish.
Warranty of Stardust Corroded Chrome Wheels
Wheels returned with pitting or spotting as a result of neglect and brake dust build-up may be
replaced one time.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean and free of prolonged exposure to brake dust
build-up. "GM of Canada" dealers require prior approval by the District Manager - Customer Care
and Service Process (DM-CCSP).
Customer Assistance and Instructions
GM has looked for ways customers may improve the appearance of wheels damaged by acidic
cleaners. The following product and procedure has been found to dramatically improve the
appearance of stained wheels. For wheels that have milky stains caused by acidic cleaners try the
following:
Notice
THE 3M CHROME AND METAL POLISH REQUIRED FOR THIS PROCEDURE IS AN
EXTREMELY AGGRESSIVE POLISH/CLEANER. THE WHEELS MUST BE CLEANED BEFORE
APPLICATION TO AVOID SCRATCHING THE WHEEL SURFACE. THIS PRODUCT WILL
REDUCE THE THICKNESS OF THE CHROME PLATING ON THE WHEEL AND IF USED
INCORRECTLY OR EXCESSIVELY MAY REMOVE THE CHROME PLATING ALL TOGETHER,
EXPOSING A LESS BRIGHT AND BRASSY COLORED SUB-LAYER. FOLLOW INSTRUCTIONS
EXACTLY.
1. Wash the wheels with vigorously with soap and water. This step will clean and may reduce
wheel staining. Flood all areas of the wheel with water
to rinse.
2. Dry the wheels completely.
Notice Begin with a small section of the wheel and with light pressure buff off polish and examine
results. ONLY apply and rub with sufficient force and time to remove enough staining that you are
satisfied with the results. Some wheels may be stained to the extent that you may only achieve a
50% improvement while others may be able to be restored to the original lustre. IN ALL CASES,
only apply until the results are satisfactory.
3. Apply 3M Chrome and Metal Polish #39527* with a clean terry cloth towel. As you apply the
polish, the staining will be diminished. 4. When dry, buff off the polish with a clean portion of the
towel. 5. Repeat application of the 3M Chrome and Metal Polish until satisfied with the results. If
continued applications fail to improve the appearance
further discontinue use.
This procedure will improve the appearance of the wheels and may, with repeated applications,
restore the finish dramatically. For wheels that exhibit spotting from road chemicals the above
procedure may marginally improve the condition but will not restore the finish or remove the pitting.
In this type of staining the wheel finish has actually been removed in spots and no manner of
cleaning will restore the finish.
†*We believe this source and their products to be reliable. There may be additional manufacturers
of such products/materials. General Motors does not endorse, indicate any preference for or
assume any responsibility for the products or material from this firm or for any such items that may
be available from other sources.
Parts Information
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3248
*This product is currently available from 3M. To obtain information for your local retail location
please call 3M at 1-888-364-3577.
**This product is currently available from Meguiars (Canada). To obtain information for your local
retail location please call Meguiars at 1-800-347-5700 or at www.meguiarscanada.com.
^ This product is currently available from Tri-Peek International. To obtain information for your local
retail location please call Tri-Peek at
1-877-615-4272 or at www.tripeek.com.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum
Wheels
Wheels: All Technical Service Bulletins Wheels/Tires - Refinishing Aluminum Wheels
INFORMATION
Bulletin No.: 99-08-51-007E
Date: March 17, 2011
Subject: Refinishing Aluminum Wheels
Models:
2012 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add additional model years. Please discard Corporate
Bulletin Number 99-08-51-007D (Section 08 - Body and Accessories).
This bulletin updates General Motor's position on refinishing aluminum wheels. GM does not
endorse any repairs that involve welding, bending, straightening or re-machining. Only cosmetic
refinishing of the wheel's coatings, using recommended procedures, is allowed.
Evaluating Damage
In evaluating damage, it is the GM Dealer's responsibility to inspect the wheel for corrosion,
scrapes, gouges, etc. The Dealer must insure that such damage is not deeper than what can be
sanded or polished off. The wheel must be inspected for cracks. If cracks are found, discard the
wheel. Any wheels with bent rim flanges must not be repaired or refinished. Wheels that have been
refinished by an outside company must be returned to the same vehicle. The Dealer must record
the wheel ID stamp or the cast date on the wheel in order to assure this requirement. Refer to
Refinisher's Responsibility - Outside Company later in this bulletin.
Aluminum Wheel Refinishing Recommendations
- Chrome-plated aluminum wheels Re-plating these wheels is not recommended.
- Polished aluminum wheels These wheels have a polyester or acrylic clearcoat on them. If the
clearcoat is damaged, refinishing is possible. However, the required refinishing process cannot be
performed in the dealer environment. Refer to Refinisher's Responsibility - Outside Company later
in this bulletin.
- Painted aluminum wheels These wheels are painted using a primer, color coat, and clearcoat
procedure. If the paint is damaged, refinishing is possible. As with polished wheels, all original
coatings must be removed first. Media blasting is recommended. Refer to GM Aluminum
Refinishing Bulletin #53-17-03A for the re-painting of this type of wheel.
- Bright, machined aluminum wheels These wheels have a polyester or acrylic clearcoat on them.
In some cases, the recessed "pocket" areas of the wheel may be painted. Surface refinishing is
possible. The wheel must be totally stripped by media blasting or other suitable means. The wheel
should be resurfaced by using a sanding process rather than a machining process. This allows the
least amount of material to be removed.
Important Do not use any re-machining process that removes aluminum. This could affect the
dimensions and function of the wheel.
Painting is an option to re-clearcoating polished and bright machined aluminum wheels. Paint will
better mask any surface imperfections and is somewhat more durable than clearcoat alone. GM
recommends using Corsican SILVER WAEQ9283 for a fine "aluminum-like" look or Sparkle
SILVER WA9967 for a very bright look. As an option, the body color may also be used. When using
any of the painting options, it is recommended that all four wheels be refinished in order to maintain
color uniformity. Refer to GM Aluminum Refinishing Bulletin #53-17-03A for specific procedures
and product recommendations.
Refinisher's Responsibility - Outside Company
Important Some outside companies are offering wheel refinishing services. Such refinished wheels
will be permanently marked by the refinisher and are warranted by the refinisher. Any process that
re-machines or otherwise re-manufactures the wheel should not be used.
A refinisher's responsibility includes inspecting for cracks using the Zyglo system or the equivalent.
Any cracked wheels must not be refinished. No welding, hammering or reforming of any kind is
allowed. The wheel ID must be recorded and follow the wheel throughout the process in order to
assure that the same wheel is returned. A plastic media blast may be used for clean up of the
wheel. Hand and/or lathe sanding of the machined surface and the wheel window is allowed.
Material removal, though, must be kept to a minimum. Re-machining of the wheel is not allowed.
Paint and/or clear coat must not be present on the following surfaces: the nut chamfers, the wheel
mounting surfaces and the wheel pilot hole. The refinisher must permanently ID stamp the wheel
and warrant the painted/clearcoated surfaces for a minimum of one year or the remainder of the
new vehicle warranty, whichever is
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum
Wheels > Page 3253
longer.
Important Whenever a wheel is refinished, the mounting surface and the wheel nut contact
surfaces must not be painted or clearcoated. Coating these surfaces could affect the wheel nut
torque.
When re-mounting a tire on an aluminum wheel, coated balance weights must be used in order to
reduce the chance of future cosmetic damage.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions
Wheels: All Technical Service Bulletins Wheels - Changing Procedures/Precautions
INFORMATION
Bulletin No.: 06-03-10-010A
Date: June 09, 2010
Subject: Information on Proper Wheel Changing Procedures and Cautions
Models:
2011 and Prior GM Passenger Cars and Trucks 2010 and Prior HUMMER Models 2005-2009 Saab
9-7X 2005-2009 Saturn Vehicles
Attention:
Complete wheel changing instructions for each vehicle line can be found under Tire and Wheel
Removal and Installation in Service Information (SI). This bulletin is intended to quickly review and
reinforce simple but vital procedures to reduce the possibility of achieving low torque during wheel
installation. Always refer to SI for wheel lug nut torque specifications and complete jacking
instructions for safe wheel changing.
Supercede: This bulletin is being revised to include the 2011 model year and update the available
special tool list. Please discard Corporate Bulletin Number 06-03-10-010 (Section 03 Suspension).
Frequency of Wheel Changes - Marketplace Driven
Just a few years ago, the increasing longevity of tires along with greater resistance to punctures
had greatly reduced the number of times wheels were removed to basically required tire rotation
intervals. Today with the booming business in accessory wheels/special application tires (such as
winter tires), consumers are having tire/wheel assemblies removed - replaced - or installed more
than ever. With this increased activity, it opens up more of a chance for error on the part of the
technician. This bulletin will review a few of the common concerns and mistakes to make yourself
aware of.
Proper Servicing Starts With the Right Tools
The following tools have been made available to assist in proper wheel and tire removal and
installation.
- J 41013 Rotor Resurfacing Kit (or equivalent)
- J 42450-A Wheel Hub Resurfacing Kit (or equivalent)
Corroded Surfaces
One area of concern is corrosion on the mating surfaces of the wheel to the hub on the vehicle.
Excessive corrosion, dirt, rust or debris built up on these surfaces can mimic a properly tightened
wheel in the service stall. Once the vehicle is driven, the debris may loosen, grind up or be washed
away from water splash. This action may result in clearance at the mating surface of the wheel and
an under-torqued condition.
Caution
Before installing a wheel, remove any buildup on the wheel mounting surface and brake drum or
brake disc mounting surface. Installing wheels with poor metal-to-metal contact at the mounting
surfaces can cause wheel nuts to loosen. This may cause a wheel to come off when the vehicle is
moving, possibly resulting in a loss of control or personal injury.
Whenever you remove the tire/wheel assemblies, you must inspect the mating surfaces. If
corrosion is found, you should remove the debris with a die grinder equipped with a fine sanding
pad, wire brush or cleaning disc. Just remove enough material to assure a clean, smooth mating
surface.
The J 41013 (or equivalent) can be used to clean the following surfaces:
- The hub mounting surface
- The brake rotor mounting surface
- The wheel mounting surface
Use the J 42450-A (or equivalent) to clean around the base of the studs and the hub.
Lubricants, Grease and Fluids
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Bulletins > All Technical Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions > Page 3258
Some customers may use penetrating oils, grease or other lubricants on wheel studs to aid in
removal or installation. Always use a suitable cleaner/solvent to remove these lubricants prior to
installing the wheel and tire assemblies. Lubricants left on the wheel studs may cause improper
readings of wheel nut torque. Always install wheels to clean, dry wheel studs ONLY.
Notice
Lubricants left on the wheel studs or vertical mounting surfaces between the wheel and the rotor or
drum may cause the wheel to work itself loose after the vehicle is driven. Always install wheels to
clean, dry wheel studs and surfaces ONLY. Beginning with 2011 model year vehicles, put a light
coating of grease, GM P/N 1051344 (in Canada, P/N 9930370), on the inner surface of the wheel
pilot hole to prevent wheel seizure to the axle or bearing hub.
Wheel Stud and Lug Nut Damage
Always inspect the wheel studs and lug nuts for signs of damage from crossthreading or abuse.
You should never have to force wheel nuts down the stud. Lug nuts that are damaged may not
retain properly, yet give the impression of fully tightening. Always inspect and replace any
component suspected of damage.
Tip
Always start wheel nuts by hand! Be certain that all wheel nut threads have been engaged
BEFORE tightening the nut.
Important If the vehicle has directional tread tires, verify the directional arrow on the outboard side
of the tire is pointing in the direction of forward rotation.
Wheel Nut Tightening and Torque
Improper wheel nut tightening can lead to brake pulsation and rotor damage. In order to avoid
additional brake repairs, evenly tighten the wheel nuts to the proper torque specification as shown
for each vehicle in SI. Always observe the proper wheel nut tightening sequence as shown below in
order to avoid trapping the wheel on the wheel stud threads or clamping the wheel slightly off
center resulting in vibration.
The Most Important Service You Provide
While the above information is well known, and wheel removal so common, technicians run the risk
of becoming complacent on this very important
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Bulletins > All Technical Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions > Page 3259
service operation. A simple distraction or time constraint that rushes the job may result in personal
injury if the greatest of care is not exercised. Make it a habit to double check your work and to
always side with caution when installing wheels.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force
Variation (RFV)
Wheels: All Technical Service Bulletins Wheels/Tires - Tire Radial Force Variation (RFV)
INFORMATION
Bulletin No.: 00-03-10-006F
Date: May 04, 2010
Subject: Information on Tire Radial Force Variation (RFV)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks 2010 and Prior HUMMER H2, H3 2009
and Prior Saab 9-7X 2000-2005 Saturn L Series 2003-2007 Saturn ION
Supercede: This bulletin is being revised to considerably expand the available information on
Radial Force Variation (RFV) and should be reviewed in whole. Please discard Corporate Bulletin
Number 00-03-10-006E (Section 03 - Suspension).
Important
- Before measuring tires on equipment such as the Hunter GSP9700, the vehicle MUST be driven
a minimum of 16 km (10 mi) to ensure removal of any flat-spotting. Refer to Corporate Bulletin
Number 03-03-10-007E - Tire/Wheel Characteristics of GM Original Equipment Tires.
- Equipment such as the Hunter GSP9700 MUST be calibrated prior to measuring tire/wheel
assemblies for each vehicle.
The purpose of this bulletin is to provide guidance to GM dealers when using tire force variation
measurement equipment, such as the Hunter GSP9700. This type of equipment can be a valuable
tool in diagnosing vehicle ride concerns. The most common ride concern involving tire radial force
variation is highway speed shake on smooth roads.
Tire related smooth road highway speed shake can be caused by three conditions: imbalance, out
of round and tire force variation. These three conditions are not necessarily related. All three
conditions must be addressed.
Imbalance is normally addressed first, because it is the simpler of the three to correct. Off-vehicle,
two plane dynamic wheel balancers are readily available and can accurately correct any
imbalance. Balancer calibration and maintenance, proper attachment of the wheel to the balancer,
and proper balance weights, are all factors required for a quality balance. However, a perfectly
balanced tire/wheel assembly can still be "oval shaped" and cause a vibration.
Before balancing, perform the following procedures.
Tire and Wheel Diagnosis
1. Set the tire pressure to the placard values. 2. With the vehicle raised, ensure the wheels are
centered on the hub by loosening all wheel nuts and hand-tightening all nuts first by hand while
shaking the wheel, then torque to specifications using a torque wrench, NOT a torque stick.
3. Visually inspect the tires and the wheels. Inspect for evidence of the following conditions and
correct as necessary:
- Missing balance weights
- Bent rim flange
- Irregular tire wear
- Incomplete bead seating
- Tire irregularities (including pressure settings)
- Mud/ice build-up in wheel
- Stones in the tire tread
- Remove any aftermarket wheels and/or tires and restore vehicle to original condition prior to
diagnosing a smooth road shake condition.
4. Road test the vehicle using the Electronic Vibration Analyzer (EVA) essential tool. Drive for a
sufficient distance on a known, smooth road
surface to duplicate the condition. Determine if the vehicle is sensitive to brake apply. If the brakes
are applied lightly and the pulsation felt in the steering wheel increases, refer to the Brakes section
of the service manual that deals with brake-induced pulsation. If you can start to hear the vibration
as a low boom noise (in addition to feeling it), but cannot see it, the vehicle likely has a first order
(one pulse per propshaft revolution) driveline vibration. Driveline first order vibrations are high
enough in frequency that most humans can start to hear them at highway speeds, but are too high
to be able to be easily seen. These issues can be caused by driveline imbalance or misalignment.
If the vehicle exhibits this low boom and the booming pulses in-and-out on a regular basis (like a
throbbing), chances are good that the vehicle could have driveline vibration. This type
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Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force
Variation (RFV) > Page 3264
of vibration is normally felt more in the "seat of the pants" than the steering wheel.
5. Next, record the Hertz (Hz) reading as displayed by the EVA onto the tire data worksheet found
at the end of this bulletin. This should be done
after a tire break-in period of at least 16 km (10 mi) at 72 km/h (45 mph) or greater, in order to
eliminate any possible tire flat-spotting. This reading confirms what the vehicle vibration frequency
is prior to vehicle service and documents the amount of improvement occurring as the result of the
various steps taken to repair. Completing the Steering Wheel Shake Worksheet below is required.
A copy of the completed worksheet must be saved with the R.O. and a copy included with any
parts returned to the Warranty Parts Center for analysis. A reading of 35 to 50 Hz typically
indicates a first order propshaft vibration. If this is the situation, refer to Corporate Bulletin Number
08-07-30-044D. Generally, a reading between 10 and 20 Hz indicates a tire/wheel vibration and if
this is the reading obtained, continue using this bulletin. If the tire 1st order vibration goes away
and stays away during this evaluation, the cause is likely tire flat-spotting. Tire flat-spotting vibration
may come and go at any speed over 72 km/h (45 mph) during the first 10 minutes of operation, if
vibration continues after 10 minutes of driving at speeds greater than 72 km/h (45 mph), tire
flat-spotting can be ruled out as the cause for vibration.
6. If flat-spotting is the cause, provide the explanation that this has occurred due to the vehicle
being parked for long periods of time and that the
nature of the tire is to take a set. Refer to Corporate Bulletin Number 03-03-10-007E: Information
on Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment
Tires.
7. If the road test indicates a shake/vibration exists, check the imbalance of each tire/wheel
assembly on a known, calibrated, off-car dynamic
balancer.Make sure the mounting surface of the wheel and the surface of the balancer are
absolutely clean and free of debris. Be sure to chose the proper cone/collet for the wheel, and
always use the pilot bore for centering. Never center the wheel using the hub-cap bore since it is
not a precision machined surface. If any assembly calls for more than 1/4 ounce on either rim
flange, remove all balance weights and rebalance to as close to zero as possible. If you can see
the vibration (along with feeling it) in the steering wheel (driving straight without your hands on the
wheel), it is very likely to be a tire/wheel first order (one pulse per revolution) disturbance. First
order disturbances can be caused by imbalance as well as non-uniformities in tires, wheels or
hubs. This first order frequency is too low for a human to hear, but if the amplitude is high enough,
it can be seen.
If a vibration or shake still exists after balancing, any out of round conditions, of the wheel, and
force variation conditions of the tire, must be addressed. Equipment such as the Hunter GSP9700
can address both (it is also a wheel balancer).
Tire radial force vibration (RFV) can be defined as the amount of stiffness variation the tire will
produce in one revolution under a constant load. Radial force variation is what the vehicle feels
because the load (weight) of the vehicle is always on the tires. Although free runout of tires (not
under load) is not always a good indicator of a smooth ride, it is critical that total tire/wheel
assembly runout be within specification.
Equipment such as the Hunter GSP9700 loads the tire, similar to on the vehicle, and measures
radial force variation of the tire/wheel assembly. Note that the wheel is affecting the tire's RFV
measurement at this point. To isolate the wheel, its runout must be measured. This can be easily
done on the Hunter, without the need to set up dial indicators. If the wheel meets the runout
specification, the tire's RFV can then be addressed.
After measuring the tire/wheel assembly under load, and the wheel alone, the machine then
calculates (predicts) the radial force variation of the tire. However, because this is a prediction that
can include mounting inaccuracies, and the load wheel is much smaller in diameter than used in
tire production, this type of service equipment should NOT be used to audit new tires. Rather, it
should be used as a service diagnostic tool to minimize radial force variation of the tire/wheel
assembly.
Equipment such as the Hunter GSP9700 does an excellent job of measuring wheel runout, and of
finding the low point of the wheel (for runout) and the high point of the tire (for radial force
variation). This allows the tire to be matched mounted to the wheel for lowest tire/wheel assembly
force variation.
The machine will simplify this process into easy steps. The following assembly radial force variation
numbers should be used as a guide:
When measuring RFV and match mounting tires perform the following steps.
Measuring Wheel Runout and Assembly Radial Force Variation
Important The completed worksheet at the end of this bulletin must be attached to the hard copy of
the repair order.
- Measure radial force variation and radial runout.
- If a road force/balancing machine is used, record the radial force variation (RFV) on the
worksheet at the end of this bulletin. It may be of benefit to have the lowest RFV assembly to the
front left corner. If the machine is not available and the EVA data suggests there is an issue, swap
the tire and wheel assemblies from the front to the back. Re-check on the EVA and if the problem
still exists, test another vehicle to find tires that do not exhibit the same frequency and swap those
tires onto the subject vehicle.
- If a runout/balancing machine is used, record the radial runout of the tire/wheel assemblies on the
worksheet at the end of this bulletin. If one or more of the tire/wheel assemblies are more than.040
in (1.02 mm), match mount the tire to the wheel to get below.040 in (1.02 mm). For sensitive
customers, readings of 0.030 inch (0.76 mm) or less are preferable, it may also be of benefit to
have the lowest runout assembly to the front left corner. If the machine is not available and the
EVA data suggests there is an issue, swap the tire and wheel assemblies from the front to the
back. Re-check on the EVA and if the problem still exists, test another vehicle to find tires that do
not exhibit the same frequency and swap those tires
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Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force
Variation (RFV) > Page 3265
onto the subject vehicle.
- After match mounting, the tire/wheel assembly must be rebalanced.
If match mounting tires to in-spec wheels produces assembly values higher than these, tire
replacement may be necessary. Replacing tires at lower values will probably mean good tires are
being condemned. Because tires can sometimes become temporarily flat-spotted, which will affect
force variation, it is important that the vehicle be driven at least 16 km (10 mi) prior to measuring.
Tire pressure must also be adjusted to the usage pressure on the vehicle's tire placard prior to
measuring.
Most GM vehicles will tolerate radial force variation up to these levels. However, some vehicles are
more sensitive, and may require lower levels. Also, there are other tire parameters that equipment
such as the Hunter GSP9700 cannot measure that may be a factor. In such cases, TAC should be
contacted for further instructions.
Important
- When mounting a GM wheel to a wheel balancer/force variation machine, always use the wheel's
center pilot hole. This is the primary centering mechanism on all GM wheels; the bolt holes are
secondary. Usually a back cone method to the machine should be used. For added accuracy and
repeatability, a flange plate should be used to clamp the wheel onto the cone and machine. This
system is offered by all balancer manufacturers in GM's dealer program.
- Any type of service equipment that removes tread rubber by grinding, buffing or truing is NOT
recommended, and may void the tire warranty. However, tires may have been ground by the tire
company as part of their tire manufacturing process. This is a legitimate procedure.
Steering Wheel Shake Worksheet
When diagnosing vibration concerns, use the following worksheet in conjunction with the
appropriate Vibration Analysis-Road testing procedure in the Vibration Correction sub-section in SI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force
Variation (RFV) > Page 3266
Refer to the appropriate section of SI for specifications and repair procedures that are related to the
vibration concern.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast
Aluminum Wheels
Wheels: All Technical Service Bulletins Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels
TECHNICAL
Bulletin No.: 05-03-10-003F
Date: April 27, 2010
Subject: Low Tire Pressure, Leaking Cast Aluminum Wheels (Repair with Adhesive Sealant)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks (Including Saturn) 2010 and Prior
HUMMER H2, H3 2009 and Prior Saab 9-7X with Cast Aluminum Wheels
Supercede: This bulletin is being revised to update the model years and the bulletin reference
information. Please discard Corporate Bulletin Number 05-03-10-003E (Section 03 - Suspension).
Condition
Some customers may comment on a low tire pressure condition.
Diagnosis of the low tire pressure condition indicates an air leak through the cast aluminum wheel.
Cause
Porosity in the cast aluminum wheel may be the cause.
Notice
This bulletin specifically addresses issues related to the wheel casting that may result in an air
leak. For issues related to corrosion of the wheel in service, please refer to Corporate Bulletin
Number 08-03-10-006C - Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light
Illuminated, Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat).
Correction
1. Remove the tire and wheel assembly from the vehicle. Refer to the appropriate service
procedure in SI. 2. Locate the leaking area by inflating the tire to 276 kPa (40 psi) and dipping the
tire/wheel assembly in a water bath, or use a spray bottle with soap
and water to locate the specific leak location.
Important
- If the porosity leak is located in the bead area of the aluminum rim (where the tire meets the rim),
the wheel should be replaced.
- If two or more leaks are located on one wheel, the wheel should be replaced.
3. If air bubbles are observed, mark the location.
- If the leak location is on the tire/rubber area, refer to Corporate Bulletin Number 04-03-10-001F Tire Puncture Repair Procedures for All Cars and Light Duty Trucks.
- If the leak is located on the aluminum wheel area, continue with the next step.
4. Inscribe a mark on the tire at the valve stem in order to indicate the orientation of the tire to the
wheel. 5. Dismount the tire from the wheel. Refer to Tire Mounting and Dismounting. 6. Remove
the tire pressure sensor. Refer to Tire Pressure Sensor removal procedure in SI. 7. Scuff the
INSIDE rim surface at the leak area with #80 grit paper and clean the area with general purpose
cleaner, such as 3M(R) General Purpose
Adhesive Cleaner, P/N 08984, or equivalent.
8. Apply a 3 mm (0.12 in) thick layer of Silicone - Adhesive/Sealant, P/N 12378478 (in Canada, use
88900041), or equivalent, to the leak area. 9. Allow for the adhesive/sealant to dry.
Notice Caution must be used when mounting the tire so as not to damage the sealer. Damaging
the repair area may result in an air leak.
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast
Aluminum Wheels > Page 3271
10. Align the inscribed mark on the tire with the valve stem on the wheel. 11. Reinstall the Tire
Pressure Sensor. Refer to Tire Pressure Sensor installation procedure in SI. 12. Mount the tire on
the wheel. Refer to Tire Mounting and Dismounting. 13. Pressurize the tire to 276 kPa (40 psi) and
inspect for leaks. 14. Adjust tire pressure to meet the placard specification. 15. Balance the
tire/wheel assembly. Refer to Tire and Wheel Assembly Balancing - Off-Vehicle. 16. Install the tire
and wheel assembly onto the vehicle. Refer to the appropriate service procedure in SI.
Parts Information
Warranty Information (excluding Saab U.S. Models)
Important The Silicone - Adhesive/Sealant comes in a case quantity of six. ONLY charge warranty
one tube of adhesive/sealant per wheel repair.
For vehicles repaired under warranty, use:
One leak repair per wheel.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes
Flat/Warning Light ON
Wheels: All Technical Service Bulletins Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON
TECHNICAL
Bulletin No.: 08-03-10-006C
Date: April 27, 2010
Subject: Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light Illuminated,
Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat)
Models:
2000-2011 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009 HUMMER H2
2006-2010 HUMMER H3 2005-2009 Saab 9-7X
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 08-03-10-006B (Section 03 - Suspension).
Condition
Some customers may comment on a tire that slowly loses air pressure over a period of days or
weeks.
Cause
Abrasive elements in the environment may intrude between the tire and wheel at the bead seat.
There is always some relative motion between the tire and wheel (when the vehicle is driven) and
this motion may cause the abrasive particles to wear the wheel and tire materials. As the wear
continues, there may also be intrusion at the tire/wheel interface by corrosive media from the
environment. Eventually a path for air develops and a 'slow' leak may ensue. This corrosion may
appear on the inboard or outboard bead seating surface of the wheel. This corrosion will not be
visible until the tire is dismounted from the wheel.
Notice
This bulletin specifically addresses issues related to wheel bead seat corrosion that may result in
an air leak. For issues related to porosity of the wheel casting that may result in an air leak, please
refer to Corporate Bulletin Number 05-03-10-006F - Low Tire Pressure, Leaking Cast Aluminum
Wheels (Repair with Adhesive Sealant)
Correction
In most cases, this type of air loss can be corrected by following the procedure below.
Important DO NOT replace a wheel for slow air loss unless you have evaluated and/or tried to
repair the wheel with the procedure below.
Notice
The repair is no longer advised or applicable for chromed aluminum wheels.
1. Remove the wheel and tire assembly for diagnosis. Refer to Tire and Wheel Removal and
Installation in SI. 2. After a water dunk tank leak test, if you determine the source of the air leak to
be around the bead seat of the wheel, dismount the tire to examine
the bead seat. Shown below is a typical area of bead seat corrosion.Typical Location of Bead Seat
Corrosion
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes
Flat/Warning Light ON > Page 3276
Important Other forms of slow air leaks are possible. If the body of the tire, valve stem and wheel
flange show no signs of air seepage, refer to Corporate Bulletin Number 05-03-10-003D for
additional information on possible wheel porosity issues.
3. Bead seat corrosion is identified by what appears like blistering of the wheel finish, causing a
rough or uneven surface that is difficult for the tire to
maintain a proper seal on. Below is a close-up photo of bead seat corrosion on an aluminum wheel
that was sufficient to cause slow air loss. Close-Up of Bead Seat Corrosion
4. If corrosion is found on the wheel bead seat, measure the affected area as shown below.
- For vehicles with 32,186 km (20,000 mi) or less, the total allowable combined linear area of
repairable corrosion is 100 mm (4 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
- For vehicles that have exceeded 32,186 km (20,000 mi), the total allowable combined linear area
of repairable corrosion is 200 mm (8 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
5. In order to correct the wheel leak, use a clean-up (fine cut) sanding disc or biscuit to remove the
corrosion and any flaking paint. You should
remove the corrosion back far enough until you reach material that is stable and firmly bonded to
the wheel. Try to taper the edge of any flaking paint as best you can in order to avoid sharp edges
that may increase the chance of a leak reoccurring. The photo below shows an acceptable repaired
surface.
Notice Corrosion that extends up the lip of the wheel, where after the clean-up process it would be
visible with the tire mounted, is only acceptable on the inboard flange. The inboard flange is not
visible with the wheel assembly in the mounted position. If any loose coatings or corrosion extend
to the visible surfaces on the FACE of the wheel, that wheel must be replaced.
Important Remove ONLY the material required to eliminate the corrosion from the bead seating
surface. DO NOT remove excessive amounts of material. ALWAYS keep the sealing surface as
smooth and level as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes
Flat/Warning Light ON > Page 3277
Acceptably Prepared (Cleaned-Up) Wheel Surface
6. Once the corrosion has been eliminated, you should coat the repaired area with a commercially
available tire sealant such as Patch Brand Bead
Sealant or equivalent. Commercially available bead sealants are black rubber-like coatings that will
permanently fill and seal the resurfaced bead seat. At 21°C (70°F) ambient temperature, this
sealant will set-up sufficiently for tire mounting in about 10 minutes.Coated and Sealed Bead Seat
7. Remount the tire and install the repaired wheel and tire assembly. Refer to Tire and Wheel
Removal and Installation in SI.
Parts Information
Patch Brand Bead Sealer is available from Myers Tires at 1-800-998-9897 or on the web at
www.myerstiresupply.com. The one-quart size can of sealer will repair about 20 wheels.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes
Flat/Warning Light ON > Page 3278
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 04-03-10-012B > Feb > 08 > Wheels - Chrome Wheel Brake Dust
Accumulation/Pitting
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Brake Dust Accumulation/Pitting
Bulletin No.: 04-03-10-012B
Date: February 01, 2008
INFORMATION
Subject: Pitting and Brake Dust on Chrome wheels
Models: 2008 and Prior GM Passenger Cars and Trucks (including Saturn) 2008 and Prior
HUMMER H2, H3 2005-2008 Saab 9-7X
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
04-03-10-012A (Section 03 - Suspension).
Analysis of Returned Wheels
Chrome wheels returned under the New Vehicle Limited Warranty for pitting concerns have
recently been evaluated. This condition is usually most severe in the vent (or window) area of the
front wheels. This "pitting" may actually be brake dust that has been allowed to accumulate on the
wheel. The longer this accumulation builds up, the more difficult it is to remove.
Cleaning the Wheels
In all cases, the returned wheels could be cleaned to their original condition using GM Vehicle Care
Cleaner Wax, P/N 12377966 (in Canada, P/N 10952905). When using this product, you should
confine your treatment to the areas of the wheel that show evidence of the brake dust build-up.
This product is only for use on chromed steel or chromed aluminum wheels.
Parts Information
Warranty Information
Wheel replacement for this condition is NOT applicable under the terms of the New Vehicle Limited
Warranty.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire
Leak/Vibration
Wheels: All Technical Service Bulletins Wheels/Tires - Slow Tire Leak/Vibration
Bulletin No.: 03-03-10-001D
Date: January 17, 2008
TECHNICAL
Subject: Tire Slowly Goes Flat and/or Excessive wheel Vibration Caused By Bead Splits (Replace
wheels with New Heavy Duty Rim Version)
Models: 1999-2006 Chevrolet Silverado 1500 Series Pickup Models (Classic) 1999-2006 Chevrolet
Express 1500 Series Vans 2000-2006 Chevrolet Suburban Tahoe 1999-2006 GMC Sierra 1500
Series Pickup Models (Classic) 1999-2006 GMC Savana 1500 Series Vans 2002-2006 GMC
Yukon Yukon XL 2007 GMC Sierra Denali Crew Cab
with 6-Bolt, 16 X 6.5 Full Face Steel wheel (Base and RPO PY2)
Supercede:
This bulletin is being revised to add the Express and Savana models and add information to the
Correction section. Please discard Corporate Bulletin Number 03-03-10-001C (Section 03 Suspension).
Implementation of this service bulletin by "GM of Canada" dealers requires prior District Service
Manager approval.
Condition
Some customers may comment on a tire that slowly goes flat and/or excessive wheel vibration.
This condition is more apparent on vehicles in which customer usage typically involves frequent
severe conditions such as:
High load (at or above gross vehicle weight)
Rough road/off road usage
Fleet/Commercial usage
Cause
The wheel may experience a crack or split in the outboard bead seat weld area. A weld attaches
the rim and disc together on full-face wheels in this area. To identify this wheel it is offered in a
silver painted version P/N 9593915 code "TZA" and a chrome-clad version, P/N 9593150 code
"RSC" (these codes are stamped into the wheel's disc near the bolt holes).
Correction
Wheel replacement should only be done for air loss and/or vibration caused by bead splits.
A new heavy-duty rim version of these wheels has been released for service. The new heavy-duty
painted wheel is P/N 9595245 code "FFU" used as a road wheel and spare. The new heavy-duty
chrome clad version is P/N 9595306 code "FFW" used as a road wheel only (these codes are
stamped into the inboard rim flange balance weight area and are also on a sticker near the bolt
holes). If a condition of a crack or split as described above occurs all (5) five of the original wheels
on the vehicle should be replaced with the new heavy-duty wheels as follows: Replace road wheel
P/N 9593915 with P/N 9595245. Replace road wheel PIN 9593150 with P/N 9595306. Replace the
spare wheel with P/N 9595245 on all vehicles.
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Wheels: > 03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire
Leak/Vibration > Page 3287
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Staining/Pitting/Corrosion
INFORMATION
Bulletin No.: 00-03-10-002F
Date: April 21, 2011
Subject: Chemical Staining, Pitting, Corrosion and/or Spotted Appearance of Chromed Aluminum
Wheels
Models:
2012 and Prior GM Cars and Trucks
Supercede: This bulletin is being revised to update model years, suggest additional restorative
products and add additional corrosion information. Please discard Corporate Bulletin Number
00-03-10-002E (Section 03 - Suspension). Important You may give a copy of this bulletin to the
customer.
What is Chemical Staining of Chrome Wheels? Figure 1
Chemical staining in most cases results from acid based cleaners (refer to Figure 1 for an
example). These stains are frequently milky, black, or greenish in appearance. They result from
using cleaning solutions that contain acids on chrome wheels. Soap and water is usually sufficient
to clean wheels.
If the customer insists on using a wheel cleaner they should only use one that specifically states
that it is safe for chromed wheels and does not contain anything in the following list. (Dealers
should also survey any products they use during prep or normal cleaning of stock units for these
chemicals.)
- Ammonium Bifluoride (fluoride source for dissolution of chrome)
- Hydrofluoric Acid (directly dissolves chrome)
- Hydrochloric Acid (directly dissolves chrome)
- Sodium Dodecylbenzenesulfonic Acid
- Sulfamic Acid
- Phosphoric Acid
- Hydroxyacetic Acid
Notice
Many wheel cleaner instructions advise to take care to avoid contact with painted surfaces. Most
customers think of painted surfaces as the fenders, quarter panels and other exterior sheet metal.
Many vehicles have painted brake calipers. Acidic wheel cleaners may craze, crack, or discolor the
paint on the brake calipers. Damage from wheel cleaners is not covered under the vehicle new car
warranty. Soap and water applied with a soft brush is usually all that is required to clean the
calipers.
Whenever any wheel cleaner is used, it must be THOROUGHLY rinsed off of the wheel with clean,
clear water. Special care must be taken to rinse under the hub cap, balance weights, wheel nuts,
lug nut caps, between the wheel cladding and off the back side of the wheel. Wheels returned to
the Warranty Parts Center (WPC) that exhibit damage from wheel cleaners most often have the
damage around and under the wheel weight where the cleaner was incompletely flushed away.
Notice
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3293
Do not use cleaning solutions that contain hydrofluoric, oxalic and most other acids on chrome
wheels (or any wheels).
If the customer is unsure of the chemical make-up of a particular wheel cleaner, it should be
avoided.
For wheels showing signs of milky staining from acidic cleaners, refer to Customer Assistance and
Instructions below.
Warranty of Stained Chrome Wheels
Stained wheels are not warrantable. Most acid based cleaners will permanently stain chrome
wheels. Follow-up with dealers has confirmed that such cleaners were used on wheels that were
returned to the Warranty Parts Center (WPC). Any stained wheels received by the WPC will be
charged back to the dealership. To assist the customer, refer to Customer Assistance and
Instructions below.
Pitting or Spotted Appearance of Chrome Wheels Figure 2
A second type or staining or finish disturbance may result from road chemicals, such as calcium
chloride used for dust control of unpaved roads. The staining will look like small pitting (refer to
Figure 2). This staining will usually be on the leading edges of each wheel spoke, but may be
uniformly distributed. If a vehicle must be operated under such conditions, the chrome wheels
should be washed with mild soap and water and thoroughly rinsed as soon as conveniently
possible.
Important Road chemicals, such as calcium chloride used for dust control of unpaved roads, can
also stain chrome wheels. The staining will look like small pitting. This staining will usually be on
the leading edges of each wheel spoke. This is explained by the vehicle traveling in the forward
direction while being splashed by the road chemical. If a vehicle must be operated under such
conditions, the chrome wheels should be washed with mild soap and water and thoroughly rinsed
as soon as conveniently possible.
Warranty of Pitted or Spotted Chrome Wheels
Wheels returned with pitting or spotting as a result of road chemicals may be replaced one time.
Damage resulting from contact with these applied road chemicals is corrosive to the wheels finish
and may cause damage if the wheels are not kept clean.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean if they are operating the vehicle in an area that
applies calcium chloride or other dust controlling chemicals! "GM of Canada" dealers require prior
approval by the District Manager - Customer Care and Service Process (DM-CCSP).
"Stardust" Corrosion of Chrome Wheels Figure 3
A third type of finish disturbance results from prolonged exposure to brake dust and resultant
penetration of brake dust through the chrome. As brakes are applied hot particles of brake material
are thrown off and tend to be forced through the leading edge of the wheel spoke windows by
airflow. These
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3294
hot particles embed themselves in the chrome layer and create a small pit. If the material is allowed
to sit on the wheel while it is exposed to moisture or salt, it will corrode the wheel beneath the
chrome leaving a pit or small blister in the chrome.
Heavy brake dust build-up should be removed from wheels by using GM Chrome Cleaner and
Polish, P/N 1050173 (in Canada use 10953013). For moderate cleaning, light brake dust build-up
or water spots use GM Swirl Remover Polish, P/N 12377965 (in Canada, use Meguiars
Plast-X(TM) Clear Plastic Cleaner and Polish #G12310C**). After cleaning, the wheel should be
waxed using GM Cleaner Wax, P/N 12377966 (in Canada, use Meguiars Cleaner Wax
#M0616C**), which will help protect the wheel from brake dust and reduce adhesion of any brake
dust that gets on the wheel surface. For general maintenance cleaning, PEEK Metal Polish† may
be used. It will clean and shine the chrome and leave behind a wax coating that may help protect
the finish.
Warranty of Stardust Corroded Chrome Wheels
Wheels returned with pitting or spotting as a result of neglect and brake dust build-up may be
replaced one time.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean and free of prolonged exposure to brake dust
build-up. "GM of Canada" dealers require prior approval by the District Manager - Customer Care
and Service Process (DM-CCSP).
Customer Assistance and Instructions
GM has looked for ways customers may improve the appearance of wheels damaged by acidic
cleaners. The following product and procedure has been found to dramatically improve the
appearance of stained wheels. For wheels that have milky stains caused by acidic cleaners try the
following:
Notice
THE 3M CHROME AND METAL POLISH REQUIRED FOR THIS PROCEDURE IS AN
EXTREMELY AGGRESSIVE POLISH/CLEANER. THE WHEELS MUST BE CLEANED BEFORE
APPLICATION TO AVOID SCRATCHING THE WHEEL SURFACE. THIS PRODUCT WILL
REDUCE THE THICKNESS OF THE CHROME PLATING ON THE WHEEL AND IF USED
INCORRECTLY OR EXCESSIVELY MAY REMOVE THE CHROME PLATING ALL TOGETHER,
EXPOSING A LESS BRIGHT AND BRASSY COLORED SUB-LAYER. FOLLOW INSTRUCTIONS
EXACTLY.
1. Wash the wheels with vigorously with soap and water. This step will clean and may reduce
wheel staining. Flood all areas of the wheel with water
to rinse.
2. Dry the wheels completely.
Notice Begin with a small section of the wheel and with light pressure buff off polish and examine
results. ONLY apply and rub with sufficient force and time to remove enough staining that you are
satisfied with the results. Some wheels may be stained to the extent that you may only achieve a
50% improvement while others may be able to be restored to the original lustre. IN ALL CASES,
only apply until the results are satisfactory.
3. Apply 3M Chrome and Metal Polish #39527* with a clean terry cloth towel. As you apply the
polish, the staining will be diminished. 4. When dry, buff off the polish with a clean portion of the
towel. 5. Repeat application of the 3M Chrome and Metal Polish until satisfied with the results. If
continued applications fail to improve the appearance
further discontinue use.
This procedure will improve the appearance of the wheels and may, with repeated applications,
restore the finish dramatically. For wheels that exhibit spotting from road chemicals the above
procedure may marginally improve the condition but will not restore the finish or remove the pitting.
In this type of staining the wheel finish has actually been removed in spots and no manner of
cleaning will restore the finish.
†*We believe this source and their products to be reliable. There may be additional manufacturers
of such products/materials. General Motors does not endorse, indicate any preference for or
assume any responsibility for the products or material from this firm or for any such items that may
be available from other sources.
Parts Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel
Staining/Pitting/Corrosion > Page 3295
*This product is currently available from 3M. To obtain information for your local retail location
please call 3M at 1-888-364-3577.
**This product is currently available from Meguiars (Canada). To obtain information for your local
retail location please call Meguiars at 1-800-347-5700 or at www.meguiarscanada.com.
^ This product is currently available from Tri-Peek International. To obtain information for your local
retail location please call Tri-Peek at
1-877-615-4272 or at www.tripeek.com.
Disclaimer
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Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum
Wheels
Wheels: All Technical Service Bulletins Wheels/Tires - Refinishing Aluminum Wheels
INFORMATION
Bulletin No.: 99-08-51-007E
Date: March 17, 2011
Subject: Refinishing Aluminum Wheels
Models:
2012 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add additional model years. Please discard Corporate
Bulletin Number 99-08-51-007D (Section 08 - Body and Accessories).
This bulletin updates General Motor's position on refinishing aluminum wheels. GM does not
endorse any repairs that involve welding, bending, straightening or re-machining. Only cosmetic
refinishing of the wheel's coatings, using recommended procedures, is allowed.
Evaluating Damage
In evaluating damage, it is the GM Dealer's responsibility to inspect the wheel for corrosion,
scrapes, gouges, etc. The Dealer must insure that such damage is not deeper than what can be
sanded or polished off. The wheel must be inspected for cracks. If cracks are found, discard the
wheel. Any wheels with bent rim flanges must not be repaired or refinished. Wheels that have been
refinished by an outside company must be returned to the same vehicle. The Dealer must record
the wheel ID stamp or the cast date on the wheel in order to assure this requirement. Refer to
Refinisher's Responsibility - Outside Company later in this bulletin.
Aluminum Wheel Refinishing Recommendations
- Chrome-plated aluminum wheels Re-plating these wheels is not recommended.
- Polished aluminum wheels These wheels have a polyester or acrylic clearcoat on them. If the
clearcoat is damaged, refinishing is possible. However, the required refinishing process cannot be
performed in the dealer environment. Refer to Refinisher's Responsibility - Outside Company later
in this bulletin.
- Painted aluminum wheels These wheels are painted using a primer, color coat, and clearcoat
procedure. If the paint is damaged, refinishing is possible. As with polished wheels, all original
coatings must be removed first. Media blasting is recommended. Refer to GM Aluminum
Refinishing Bulletin #53-17-03A for the re-painting of this type of wheel.
- Bright, machined aluminum wheels These wheels have a polyester or acrylic clearcoat on them.
In some cases, the recessed "pocket" areas of the wheel may be painted. Surface refinishing is
possible. The wheel must be totally stripped by media blasting or other suitable means. The wheel
should be resurfaced by using a sanding process rather than a machining process. This allows the
least amount of material to be removed.
Important Do not use any re-machining process that removes aluminum. This could affect the
dimensions and function of the wheel.
Painting is an option to re-clearcoating polished and bright machined aluminum wheels. Paint will
better mask any surface imperfections and is somewhat more durable than clearcoat alone. GM
recommends using Corsican SILVER WAEQ9283 for a fine "aluminum-like" look or Sparkle
SILVER WA9967 for a very bright look. As an option, the body color may also be used. When using
any of the painting options, it is recommended that all four wheels be refinished in order to maintain
color uniformity. Refer to GM Aluminum Refinishing Bulletin #53-17-03A for specific procedures
and product recommendations.
Refinisher's Responsibility - Outside Company
Important Some outside companies are offering wheel refinishing services. Such refinished wheels
will be permanently marked by the refinisher and are warranted by the refinisher. Any process that
re-machines or otherwise re-manufactures the wheel should not be used.
A refinisher's responsibility includes inspecting for cracks using the Zyglo system or the equivalent.
Any cracked wheels must not be refinished. No welding, hammering or reforming of any kind is
allowed. The wheel ID must be recorded and follow the wheel throughout the process in order to
assure that the same wheel is returned. A plastic media blast may be used for clean up of the
wheel. Hand and/or lathe sanding of the machined surface and the wheel window is allowed.
Material removal, though, must be kept to a minimum. Re-machining of the wheel is not allowed.
Paint and/or clear coat must not be present on the following surfaces: the nut chamfers, the wheel
mounting surfaces and the wheel pilot hole. The refinisher must permanently ID stamp the wheel
and warrant the painted/clearcoated surfaces for a minimum of one year or the remainder of the
new vehicle warranty, whichever is
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum
Wheels > Page 3300
longer.
Important Whenever a wheel is refinished, the mounting surface and the wheel nut contact
surfaces must not be painted or clearcoated. Coating these surfaces could affect the wheel nut
torque.
When re-mounting a tire on an aluminum wheel, coated balance weights must be used in order to
reduce the chance of future cosmetic damage.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions
Wheels: All Technical Service Bulletins Wheels - Changing Procedures/Precautions
INFORMATION
Bulletin No.: 06-03-10-010A
Date: June 09, 2010
Subject: Information on Proper Wheel Changing Procedures and Cautions
Models:
2011 and Prior GM Passenger Cars and Trucks 2010 and Prior HUMMER Models 2005-2009 Saab
9-7X 2005-2009 Saturn Vehicles
Attention:
Complete wheel changing instructions for each vehicle line can be found under Tire and Wheel
Removal and Installation in Service Information (SI). This bulletin is intended to quickly review and
reinforce simple but vital procedures to reduce the possibility of achieving low torque during wheel
installation. Always refer to SI for wheel lug nut torque specifications and complete jacking
instructions for safe wheel changing.
Supercede: This bulletin is being revised to include the 2011 model year and update the available
special tool list. Please discard Corporate Bulletin Number 06-03-10-010 (Section 03 Suspension).
Frequency of Wheel Changes - Marketplace Driven
Just a few years ago, the increasing longevity of tires along with greater resistance to punctures
had greatly reduced the number of times wheels were removed to basically required tire rotation
intervals. Today with the booming business in accessory wheels/special application tires (such as
winter tires), consumers are having tire/wheel assemblies removed - replaced - or installed more
than ever. With this increased activity, it opens up more of a chance for error on the part of the
technician. This bulletin will review a few of the common concerns and mistakes to make yourself
aware of.
Proper Servicing Starts With the Right Tools
The following tools have been made available to assist in proper wheel and tire removal and
installation.
- J 41013 Rotor Resurfacing Kit (or equivalent)
- J 42450-A Wheel Hub Resurfacing Kit (or equivalent)
Corroded Surfaces
One area of concern is corrosion on the mating surfaces of the wheel to the hub on the vehicle.
Excessive corrosion, dirt, rust or debris built up on these surfaces can mimic a properly tightened
wheel in the service stall. Once the vehicle is driven, the debris may loosen, grind up or be washed
away from water splash. This action may result in clearance at the mating surface of the wheel and
an under-torqued condition.
Caution
Before installing a wheel, remove any buildup on the wheel mounting surface and brake drum or
brake disc mounting surface. Installing wheels with poor metal-to-metal contact at the mounting
surfaces can cause wheel nuts to loosen. This may cause a wheel to come off when the vehicle is
moving, possibly resulting in a loss of control or personal injury.
Whenever you remove the tire/wheel assemblies, you must inspect the mating surfaces. If
corrosion is found, you should remove the debris with a die grinder equipped with a fine sanding
pad, wire brush or cleaning disc. Just remove enough material to assure a clean, smooth mating
surface.
The J 41013 (or equivalent) can be used to clean the following surfaces:
- The hub mounting surface
- The brake rotor mounting surface
- The wheel mounting surface
Use the J 42450-A (or equivalent) to clean around the base of the studs and the hub.
Lubricants, Grease and Fluids
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions > Page 3305
Some customers may use penetrating oils, grease or other lubricants on wheel studs to aid in
removal or installation. Always use a suitable cleaner/solvent to remove these lubricants prior to
installing the wheel and tire assemblies. Lubricants left on the wheel studs may cause improper
readings of wheel nut torque. Always install wheels to clean, dry wheel studs ONLY.
Notice
Lubricants left on the wheel studs or vertical mounting surfaces between the wheel and the rotor or
drum may cause the wheel to work itself loose after the vehicle is driven. Always install wheels to
clean, dry wheel studs and surfaces ONLY. Beginning with 2011 model year vehicles, put a light
coating of grease, GM P/N 1051344 (in Canada, P/N 9930370), on the inner surface of the wheel
pilot hole to prevent wheel seizure to the axle or bearing hub.
Wheel Stud and Lug Nut Damage
Always inspect the wheel studs and lug nuts for signs of damage from crossthreading or abuse.
You should never have to force wheel nuts down the stud. Lug nuts that are damaged may not
retain properly, yet give the impression of fully tightening. Always inspect and replace any
component suspected of damage.
Tip
Always start wheel nuts by hand! Be certain that all wheel nut threads have been engaged
BEFORE tightening the nut.
Important If the vehicle has directional tread tires, verify the directional arrow on the outboard side
of the tire is pointing in the direction of forward rotation.
Wheel Nut Tightening and Torque
Improper wheel nut tightening can lead to brake pulsation and rotor damage. In order to avoid
additional brake repairs, evenly tighten the wheel nuts to the proper torque specification as shown
for each vehicle in SI. Always observe the proper wheel nut tightening sequence as shown below in
order to avoid trapping the wheel on the wheel stud threads or clamping the wheel slightly off
center resulting in vibration.
The Most Important Service You Provide
While the above information is well known, and wheel removal so common, technicians run the risk
of becoming complacent on this very important
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 06-03-10-010A > Jun > 10 > Wheels - Changing
Procedures/Precautions > Page 3306
service operation. A simple distraction or time constraint that rushes the job may result in personal
injury if the greatest of care is not exercised. Make it a habit to double check your work and to
always side with caution when installing wheels.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Wheels: > 04-03-10-012B > Feb > 08 > Wheels - Chrome Wheel Brake Dust
Accumulation/Pitting
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Brake Dust Accumulation/Pitting
Bulletin No.: 04-03-10-012B
Date: February 01, 2008
INFORMATION
Subject: Pitting and Brake Dust on Chrome wheels
Models: 2008 and Prior GM Passenger Cars and Trucks (including Saturn) 2008 and Prior
HUMMER H2, H3 2005-2008 Saab 9-7X
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
04-03-10-012A (Section 03 - Suspension).
Analysis of Returned Wheels
Chrome wheels returned under the New Vehicle Limited Warranty for pitting concerns have
recently been evaluated. This condition is usually most severe in the vent (or window) area of the
front wheels. This "pitting" may actually be brake dust that has been allowed to accumulate on the
wheel. The longer this accumulation builds up, the more difficult it is to remove.
Cleaning the Wheels
In all cases, the returned wheels could be cleaned to their original condition using GM Vehicle Care
Cleaner Wax, P/N 12377966 (in Canada, P/N 10952905). When using this product, you should
confine your treatment to the areas of the wheel that show evidence of the brake dust build-up.
This product is only for use on chromed steel or chromed aluminum wheels.
Parts Information
Warranty Information
Wheel replacement for this condition is NOT applicable under the terms of the New Vehicle Limited
Warranty.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Page 3311
Wheels: Testing and Inspection
Wheel Mounting Surface Check
Replace any wheels that are bent or dented, or have excessive lateral or radial runout. Wheels with
runout greater than specified may cause objectionable vibrations.
1. Use a straight edge 203 - 229 mm (8 - 9 inch) long. Place the straight edge on the wheel inboard
mounting surface. Try to rock the straightedge up
and down within the mounting surface.
2. Repeat this procedure on at least 3-4 different positions on the inboard mounting surface.
^ The outer ring of the mounting surface normally is raised above everything inside the mounting
surface.
^ The mounting surface will be raised above the outer ring if the wheel mounting surface has been
bent on a tire changer.
^ If you can rock the straight edge, the mounting surface is bent and you must replace the wheel.
3. Inspect the mounting wheel/nut holes for damage caused from over-torquing the wheel/nuts.
Inspect for collapsed wheel/nut bosses. Inspect for
cracked wheel bosses.
Notice: The use of non-GM original equipment wheels may cause: ^
Damage to the wheel bearing, the wheel fasteners and the wheel
^ Tire damage caused by the modified clearance to the adjacent vehicle components
^ Adverse vehicle steering stability caused by the modified scrub radius
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Technical Service
Bulletins > Page 3312
^ Damage to the vehicle caused by the modified ground clearance
^ Speedometer and odometer inaccuracy
Important: ^
Replacement wheels must be equivalent to the original equipment wheels in the following ways: The load capacity
- The wheel diameter
- The rim width
- The wheel offset
- The mounting configuration
^ A wheel of the incorrect size or type may affect the following conditions: Wheel and hub-bearing life
- Brake cooling
- Speedometer/odometer calibration
- Vehicle ground clearance
- Tire clearance to the body and the chassis
4. Replace the wheel if the wheel is bent. 5. Replace the wheel if the wheel/nut boss area is
cracked. Identify steel wheels with a 2 or 3-letter code stamped into the rim near the valve stem.
Aluminum wheels have the code, the part number, and the manufacturer identification cast into the
back side of the wheel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Service and Repair
> Aluminum Wheel Porosity Repair
Wheels: Service and Repair Aluminum Wheel Porosity Repair
Aluminum Wheel Porosity Repair
Repair Instructions
1. Remove the tire and wheel. 2. Inflate the tire to the manufactures specified pressure as stated
on the tire. 3. Submerge the tire/wheel into a water bath in order to locate the leak. 4. Inscribe a
mark on the wheel in order to indicate the leak areas. 5. Inscribe a mark on the tire at the valve
stem in order to Indicate the orientation of the tire to the wheel. 6. Remove the tire from the wheel.
Important: Do not damage the exterior surface of the wheel.
7. Use number 80 grit sandpaper to scuff the inside of the rim surface at the leak area. 8. Use
general purpose cleaner such as EMS, P/N 08984 or equivalent, to clean the leak area. 9. Apply 3
mm (0.12 inch) thick layer of adhesive/sealant, GM P/N 12378478 (Canadian P/N 88900041) or
equivalent, to the leak area.
10. Allow for the adhesive/sealant to dry. 11. Align the inscribed mark on the tire with the valve
stem on the wheel. 12. Install the tire to the wheel. 13. Inflate the tire to the manufactures specified
pressure as stated on the tire. 14. Submerge the tire/wheel into a water bath in order ensure the
leak is sealed. 15. Balance the tire and wheel. 16. Install the tire and wheel. 17. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Service and Repair
> Aluminum Wheel Porosity Repair > Page 3315
Wheels: Service and Repair Aluminum Wheel Refinishing
Aluminum Wheel Refinishing
A protective clear coating covers the surface of original equipment cast aluminum wheels. A
surface degradation may develop if frequent automatic car wash cleaning wears off the factory
applied protective clear coating. This can happen at some automatic car wash facilities that use
aggressive brushes to clean whitewalls and tires. Once you damage the protective clear coating,
exposure to caustic cleaners and road salt can cause further surface deterioration. Damage to the
protective clear coating is corrected by replacing the damaged wheel. Refinishing is no longer
recommended.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Service and Repair
> Aluminum Wheel Porosity Repair > Page 3316
Wheels: Service and Repair Tire and Wheel Removal and Installation
Tire and Wheel Removal and Installation
Tools Required ^
J39544-KIT Complete Torque Socket Set
Caution: If penetrating oil gets on the vertical surfaces between the wheel and the rotor or drum it
could cause the wheel to work loose as the vehicle is driven, resulting in loss of control and an
injury accident.
Notice: Never use heat to loosen a tight wheel. It can shorten the life of the wheel, studs, or hub
and bearing assemblies. Wheel nuts must be tightened in sequence and to the specified torque to
avoid bending the wheel or rotor.
Notice: Improperly tightened wheel nuts can lead to brake pulsation and rotor damage. In order to
avoid expensive brake repairs, evenly tighten the wheel nuts to the proper torque specification.
Important: Removing wheels can be difficult because of foreign material or a tight fit between the
wheel center hole and the hub or rotor. Excessive force, such as hammering on the wheel or tire,
can cause damage. Slightly tapping the tire side wall with a rubber mallet is acceptable.
1. Tighten all wheel nuts on the affected wheel. 2. Loosen each wheel nut two turns. 3. Rock the
vehicle from side to side in order to loosen the wheel. If this does not loosen the wheel, rock the
vehicle front to back applying quick
hard jabs to the brake pedal to loosen the wheel.
4. Repeat this procedure if the wheel does not break free.
Removal Procedure
1. Raise the vehicle. Support the vehicle with suitable safety stands. Refer to Vehicle Lifting.
2. Remove the wheel nuts from the tire and wheel. 3. Mark the location of the tire and wheel to the
hub assembly. 4. Remove the tire and wheel from the vehicle. 5. Clean the wheel nuts, studs and
the wheel and rotor mounting surfaces.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheels > Component Information > Service and Repair
> Aluminum Wheel Porosity Repair > Page 3317
Caution: Before installing the wheels, remove any buildup of corrosion on the wheel mounting
surface and brake drum or disc mounting surface by scraping and wire brushing. Installing wheels
with poor metal-to-metal contact at the mounting surfaces can cause wheel nuts to loosen. This
can cause a wheel to come off when the vehicle is moving, causing loss of control and possibly
personal injury.
Notice: A torque wrench or J39544 must be used to ensure that wheel nuts are tightened to
specification. Never use lubricants or penetrating fluids on wheel stud, nuts, or mounting surfaces,
as this can raise the actual torque on the nut without a corresponding torque reading on the torque
wrench. Wheel nuts, studs, and mounting surfaces must be clean and dry. Failure to follow these
instructions could result in wheel, nut, and/or stud damage.
1. Install the tire and wheel. Align the locating mark of the tire and wheel to the hub.
Notice: Refer to Fastener Notice in Service Precautions.
Important: Tighten the nuts evenly and alternately in order to avoid excessive runout.
2. Install the wheel nuts.
Tighten the wheel nuts as shown to 190 Nm (140 ft. lbs.).
3. Remove the safety stands. 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Bearing > Component Information > Technical
Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure
Wheel Bearing: Technical Service Bulletins Drive Train - Revised Wheel Bearing Adjustment
Procedure
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-20-002
Date: May, 2002
SERVICE MANUAL UPDATE
Subject: Revised Wheel Bearing Adjustment Procedure
Models:
2001-2002 Chevrolet and GMC C/K and G-Van Models with 10.5 and 11.5 Inch Axles
This bulletin is being issued to revise the Wheel Bearing Adjustment procedure in the Rear Drive
Axle sub-section of the Service Manual. Please replace the current information in the Service
Manual with the following information.
The following information has been updated within Service Information (SI). If you are using a
paper version of this Service Manual, please make a reference to this bulletin on the affected page.
Wheel Bearing Adjustment
Preliminary Inspection
Important:
Ensure the brakes are fully released and do not drag.
Pull or push the tire at the top back and forth in order to test the wheel bearing play.
^ Use a pry bar under the tire as an alternative.
^ If the wheel bearing adjustment is correct, the movement will be barely noticeable.
^ If the movement is excessive, adjust the bearings.
Adjustment Procedure Tools Required J 2222-C Wheel Bearing Nut Wrench
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the axle shaft. Refer to Rear Axle Shaft and/or Gasket Replacement.
3. Remove the hub adjuster nut retaining ring.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Bearing > Component Information > Technical
Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure > Page 3322
4. Remove the adjuster nut lock key.
Notice:
Refer to Fastener Notice in Cautions and Notices.
5. Tighten the wheel bearing adjusting nut using the J 2222-C.
Rotate the hub in the opposite direction to the way the adjuster nut is turning.
Ensure the inner bearing and the seal seats against the spindle shoulder.
Tighten
Tighten the adjusting nut to 70 N.m (52 lb ft).
6. Turn the adjusting nut counterclockwise until the nut is loose using the J 2222-C.
7. Turn the adjusting nut clockwise until the nut contacts the bearing cone. Torque on the nut must
be zero to finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Bearing > Component Information > Technical
Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure > Page 3323
8. Insert the adjusting nut lock key into the keyway using one of the following procedures:
^ If the adjusting nut slot is in alignment with the keyway in the axle spindle, insert the adjusting nut
lock key into the keyway in the axle spindle.
Important:
Do not turn the adjusting nut more than one slot counterclockwise in order to align the adjusting nut
slot with the keyway in the axle spindle.
^ If the adjusting nut slot is not aligned with the keyway in the axle spindle, turn the adjusting nut
counterclockwise until the adjusting nut slot is in alignment with the keyway in the axle spindle and
insert the adjusting nut lock key.
9. Install the retaining ring.
10. Install the axle shaft. Refer to Rear Axle Shaft and/or Gasket Replacement.
11. Inspect the lubricant level and add, if necessary. Refer to Lubricant Level Check.
12. Lower the vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Bearing > Component Information > Technical
Service Bulletins > Page 3324
Wheel Bearing: Service and Repair
"For information regarding this component please refer to wheel hub service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Cover > Component Information > Technical
Service Bulletins > Wheels - Correct Hub Cap Installation Procedure
Wheel Cover: Technical Service Bulletins Wheels - Correct Hub Cap Installation Procedure
Bulletin No.: 03-03-10-002B
Date: November 02, 2005
INFORMATION
Subject: Use of Correct Installation Procedure for Loose Hubcap Assembly
Models: 1998-2006 Chevrolet Express Van 1999-2006 Chevrolet Silverado Models 2000-2006
Chevrolet Suburban, Tahoe Models 2002-2006 Chevrolet Avalanche 1998-2006 GMC Savana Van
1999-2006 GMC Sierra Models 2000-2006 GMC Yukon, Yukon XL Models
Supercede:
This bulletin is being revised to add the 2006 model year. Please discard Corporate Bulletin
Number 03-03-10-002A (Section 03 - Suspension).
Some hubcap assemblies on the above-listed vehicles are being returned to the Warranty Parts
Center (WPC) for loose and/or rattle conditions. Some returned hubcaps have the stand-off
insulators removed. Analyses of these parts show no out of specification condition.
Hubcap assemblies are placed in the vehicle by the assembly plant for dealer installation.
Installation is done by threading the six or eight plastic nut caps, which are part of the hubcap
assembly, to the external threads of the wheel (lug) nuts.
If over-tightened, these plastic nut caps will jump threads, as designed, causing a loose or rattle
condition.
Important:
^ DO NOT over-tighten the plastic nut caps.
^ DO NOT use an impact wrench on the plastic nut caps.
^ DO NOT modify or remove the stand-off insulators from the plastic hubcap assembly.
The nut cap system is designed to skip a thread if over-tightened. DO NOT replace the hubcap
assembly if this happens.
Hold hubcap (2) firmly in place on wheel with the plastic wheel nut caps (3) aligned with the steel
wheel nuts (1). Hand snug each nut cap (3) (using a hand held deep socket or torque stick) until
fully seated against the hubcap (2). You should feel the nut cap (3) ratchet against the hubcap (2) a
couple times as the nut cap (3) seats. After all nut caps (3) have been seated, check tightness of
each nut cap (3) using the socket or torque stick and tighten any nut cap (3) that may have
loosened. If a nut cap (3) jumps thread (a design feature to prevent damage) and becomes loose
during tightening, continue to tighten and stop short of thread jump.
Follow the installation instruction sheet that is included in each hubcap package.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Cover > Component Information > Technical
Service Bulletins > Wheels - Correct Hub Cap Installation Procedure > Page 3329
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Hub > Axle Nut > Component Information >
Specifications
Axle Nut: Specifications
Front Axle Shaft Nut ............................................................................................................................
................................................ 210 Nm (155 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Technical
Service Bulletins > Customer Interest for Wheel Fastener: > 01-03-10-009A > Jul > 04 > Wheels - Plastic Wheel Nut Covers
Loose/Missing
Wheel Fastener: Customer Interest Wheels - Plastic Wheel Nut Covers Loose/Missing
Bulletin No.: 01-03-10-009A
Date: July 27, 2004
TECHNICAL
Subject: Plastic Wheel Nut Covers Missing and/or Loose (Replace Missing Covers and Add
Sealant to All Covers)
Models: 2005 and All Prior Passenger Cars (Except All Cadillac Models and Pontiac GTO)
with Plastic Wheel Nut Covers
Supercede:
This bulletin is being revised to add additional models years. Please discard Corporate Bulletin
Number 01-03-10-009.
Condition
Some customers may comment that the plastic wheel nut covers are missing and/or loose.
Correction
Important:
^ DO NOT USE a silicone-based adhesive.
^ Do not apply the *permatex(R) around the threads in a circular pattern.
^ Apply a single bead across the threads approximately 10 mm (0.4 in) in length, 5 mm (0.2 in) in
height and 5 mm (0.2 in) in width.
Replace any missing plastic wheel nut covers with the appropriate covers and apply Permatex(R) #
2 Form A Gasket Sealant(R) to the threads of all the plastic wheel nut covers. Tighten finger tight
plus a 1/4 turn with a hand wrench.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such material.
General Motors does not endorse, indicate any preference for or assume any responsibility for the
products from this firm or for any other such items which may be available from other sources.
Permatex(R) # 2 Form A Gasket Sealant(R) part numbers (available at your local parts supplier)
^ P/N 80009 (2A/2AR) - 44 ml (1.5 oz) tube boxed
^ P/N 80015 (2AR) - 44 ml (1.5 oz) tube carded
^ P/N 80010 (2B/2BR) - 89 ml (3 oz) tube boxed
^ P/N 80016 (2BR) - 89 ml (3 oz) tube carded
^ P/N 80011 (2C) - 325 ml (11 oz) tube boxed
Warranty Information
For vehicles repaired under warranty, use the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Technical
Service Bulletins > Customer Interest for Wheel Fastener: > 01-03-10-009A > Jul > 04 > Wheels - Plastic Wheel Nut Covers
Loose/Missing > Page 3342
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wheel Fastener: > 01-03-10-009A > Jul > 04 > Wheels - Plastic Wheel
Nut Covers Loose/Missing
Wheel Fastener: All Technical Service Bulletins Wheels - Plastic Wheel Nut Covers Loose/Missing
Bulletin No.: 01-03-10-009A
Date: July 27, 2004
TECHNICAL
Subject: Plastic Wheel Nut Covers Missing and/or Loose (Replace Missing Covers and Add
Sealant to All Covers)
Models: 2005 and All Prior Passenger Cars (Except All Cadillac Models and Pontiac GTO)
with Plastic Wheel Nut Covers
Supercede:
This bulletin is being revised to add additional models years. Please discard Corporate Bulletin
Number 01-03-10-009.
Condition
Some customers may comment that the plastic wheel nut covers are missing and/or loose.
Correction
Important:
^ DO NOT USE a silicone-based adhesive.
^ Do not apply the *permatex(R) around the threads in a circular pattern.
^ Apply a single bead across the threads approximately 10 mm (0.4 in) in length, 5 mm (0.2 in) in
height and 5 mm (0.2 in) in width.
Replace any missing plastic wheel nut covers with the appropriate covers and apply Permatex(R) #
2 Form A Gasket Sealant(R) to the threads of all the plastic wheel nut covers. Tighten finger tight
plus a 1/4 turn with a hand wrench.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such material.
General Motors does not endorse, indicate any preference for or assume any responsibility for the
products from this firm or for any other such items which may be available from other sources.
Permatex(R) # 2 Form A Gasket Sealant(R) part numbers (available at your local parts supplier)
^ P/N 80009 (2A/2AR) - 44 ml (1.5 oz) tube boxed
^ P/N 80015 (2AR) - 44 ml (1.5 oz) tube carded
^ P/N 80010 (2B/2BR) - 89 ml (3 oz) tube boxed
^ P/N 80016 (2BR) - 89 ml (3 oz) tube carded
^ P/N 80011 (2C) - 325 ml (11 oz) tube boxed
Warranty Information
For vehicles repaired under warranty, use the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wheel Fastener: > 01-03-10-009A > Jul > 04 > Wheels - Plastic Wheel
Nut Covers Loose/Missing > Page 3348
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information >
Specifications > Wheel Nut Torque
Wheel Fastener: Specifications Wheel Nut Torque
Single Wheel Nuts ...............................................................................................................................
................................................. 190 Nm (140 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information >
Specifications > Wheel Nut Torque > Page 3351
Lug Nut Torque Patterns
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Service
and Repair > Front
Wheel Fastener: Service and Repair Front
Wheel Stud Replacement
Tools Required ^
J43631 Ball Joint Remover
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the brake rotor.
4. Remove the wheel stud from the hub flange using the J43631. 5. Remove the wheel stud from
the hub flange.
Installation Procedure
1. Install the new stud into the hub flange hole using firm hand pressure. 2. Install 4 washers to the
new wheel stud.
3. Thread a wheel nut onto the new stud with the flat side facing the front hub flange. 4. Tighten the
lug nut until the stud contacts the back of the hub flange. 5. Remove the wheel nut. 6. Remove the
washers. 7. Install the brake rotor. 8. Install the tire and wheel. 9. Remove the safety stands.
10. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Fastener > Component Information > Service
and Repair > Front > Page 3354
Wheel Fastener: Service and Repair Rear
Wheel Stud Replacement
Tools Required ^
J43631 Ball Joint Remover
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the rotor. 4. Remove the wheel stud from the axle flange using the J43631 for the 15 series. 5.
Remove the axle shaft for vehicles with 9.5 inch ring gear. 6. Remove the rear hub assembly for
vehicles with 10.5 in ring gear.
7. Remove the wheel stud from the axle flange using the J43631. 8. Remove the wheel stud from
the hub flange using the J43631.
Installation Procedure
1. Install the stud into the axle flange for the 15 Series.
2. Install the 4 washers and the lug nut to the stud. 3. Tighten the lug nut in order to draw the stud
into the flange until the stud fully seats. 4. Remove the lug nut and the washers. 5. Install the axle
shaft for the vehicles with 9.5 in ring gear. 6. Install the rear hub assembly for the vehicles with 10.5
in ring gear. 7. Install the rotor. 8. Install the tire and wheel. 9. Remove the safety stands.
10. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Maintenance > Wheels and Tires > Wheel Seal > Component Information > Service and
Repair
Wheel Seal: Service and Repair
"For information regarding this component please refer to wheel hub service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Compression Check > System Information >
Specifications
Compression Check: Specifications
The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure
in any one cylinder is 1035 kPa (150 psi), the lowest allowable pressure for any other cylinder
would be 725 kPa (105 psi). (1035 x 70% = 725) (150 x 70% = 105).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Compression Check > System Information >
System Diagnosis > Engine Compression Test (Electronic Throttle)
Compression Check: Testing and Inspection Engine Compression Test (Electronic Throttle)
Engine Compression Test (Electronic Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Turn the ignition to the ON position. 6.
Depress the accelerator pedal to position the throttle plate wide open. 7. Start with the compression
gauge at zero and crank the engine through four compression strokes, four puffs. 8. Check the
compression for each cylinder. Record the readings. 9. If a cylinder has low compression, inject
approximately 15 ml. (1 tablespoon) of engine oil into the combustion chamber through the spark
plug
hole. Recheck the compression and record the reading.
10. The minimum compression in any one cylinder should not be less than 70 percent of the
highest cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Then compression builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Compression Check > System Information >
System Diagnosis > Engine Compression Test (Electronic Throttle) > Page 3365
Compression Check: Testing and Inspection Engine Compression Test (Mechanical Throttle)
Engine Compression Test (Mechanical Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Block the throttle plate wide open. 6.
Start with the compression gauge at zero and crank the engine through four compression strokes,
four puffs. 7. Make the compression check for each cylinder. Record the reading. 8. If a cylinder
has low compression, inject approximately 15 ml. (1 tablespoon) of engine oil into the combustion
chamber through the spark plug
hole. Recheck the compression and record the reading.
9. The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Compression then builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Engine Mechanical Specifications
Camshaft: Specifications Engine Mechanical Specifications
Camshaft
Camshaft End Play
........................................................................................................................................................
0.025-0.305 mm (0.001-0.012 inch) Camshaft Journal Diameter
...........................................................................................................................................
54.99-55.04 mm (2.164-2.166 inch) Camshaft Journal Diameter Out-of-Round
........................................................................................................................................ 0.025 mm
(0.001 inch) Camshaft Lobe Lift (Intake) .............................................................................................
................................................................... 6.82 mm (0.268 inch) Camshaft Lobe Lift (Exhaust)
..............................................................................................................................................................
6.96 mm (0.274 inch) Camshaft Runout (Measured at the Intermediate Journals)
................................................................................................................. 0.05 mm (0.002 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Engine Mechanical Specifications > Page 3371
Camshaft: Specifications Fastener Tightening Specifications
Camshaft Retainer Bolt .......................................................................................................................
...................................................... 25 Nm (18 ft. lbs.) Camshaft Sensor Bolt .....................................
.......................................................................................................................................... 25 Nm (18
ft. lbs.) Camshaft Sprocket Bolt ...........................................................................................................
................................................................. 35 Nm (28 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Page 3372
Camshaft: Service and Repair
Camshaft Replacement
Removal Procedure
1. Raise the hood to the servicing position, perform the following:
- Remove the hood hinge bolts (1).
- Raise the hood until vertical.
- Install the hood hinge bolts until snug in the service position (2).
2. Remove the radiator support. 3. Remove the timing chain and camshaft sprocket. 4. Remove the
valve lifters from both cylinder heads.
5. Remove the camshaft sensor bolt and sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Page 3373
6. Remove the camshaft retainer bolts and retainer.
Notice: All camshaft journals are the same diameter, so care must be used in removing or installing
the camshaft to avoid damage to the camshaft bearings.
7. Remove the camshaft.
7.1. Install three M8-1.25 x 100 mm (M8-1.25 x 4.0 inch) bolts to the bolt holes in the front of the
camshaft.
7.2. Using the bolts as a handle, carefully rotate and pull the camshaft out of the engine block.
7.3. Remove the three bolts from the camshaft.
8. Clean and inspect the camshaft and bearings.
Installation Procedure
Important: If camshaft replacement is required, the valve lifters must also be replaced.
1. Lubricate the camshaft journals and the bearings with clean engine oil. 2. Install three M8-1.25 x
100 mm (M8-1.25 x 4.0 inch) bolts to the bolt holes in the front of the camshaft.
Notice: All camshaft journals are the same diameter, so care must be used in removing or installing
the camshaft to avoid damage to the camshaft bearings.
3. Using the bolts as a handle, carefully install the camshaft into the engine block. 4. Remove the
three bolts from the front of the camshaft.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Page 3374
Important: Install the retainer plate with the sealing gasket facing the engine block. The gasket
surface on the engine block should be clean and free of dirt and/or debris.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the camshaft retainer and bolts.
- Tighten the camshaft retainer bolts to 25 Nm (18 ft. lbs.).
6. Inspect the camshaft sensor O-ring seal. If the O-ring seal is not cut or damaged, it may be
reused. 7. Lubricate the O-ring seal with clean engine oil. 8. Install the camshaft sensor and bolt.
- Tighten the camshaft sensor bolt to 25 Nm (18 ft. lbs.).
9. Install the timing chain and camshaft sprocket.
10. Install the valve lifters. 11. Install the radiator support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Camshaft,
Engine > Component Information > Specifications > Page 3375
12. Remove the hood hinge bolts from the service position (2). 13. Lower the hood to the normal
position. 14. Install the hood hinge bolts.
- Tighten the hood hinge bolts to 25 Nm (18 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Lifter / Lash
Adjuster, Valve > Component Information > Specifications
Lifter / Lash Adjuster: Specifications
Valve Lifter Guide Bolt .........................................................................................................................
.............................................. 12 Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Lifter / Lash
Adjuster, Valve > Component Information > Specifications > Page 3379
Lifter / Lash Adjuster: Service and Repair
Valve Lifter Replacement
- Tools Required J 3049-A Valve Lifter Remover
Removal Procedure
1. Remove the cylinder head and gasket. 2. Remove the valve lifter guide bolts (1). 3. Remove the
valve lifters and guide.
Important: Some valve lifters may be stuck in their bores because of gum or varnish deposits.
4. Use J 3049-A or equivalent in order to remove the valve lifters (if required).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Lifter / Lash
Adjuster, Valve > Component Information > Specifications > Page 3380
5. Remove the valve lifters from the guide. 6. Organize or mark the components so that they can
be installed in the same location from which they were removed. 7. Clean and inspect the valve
liners.
Installation Procedure
Important: When reusing valve lifters, install the lifters to their original locations.
1. Lubricate the valve lifters and engine block valve lifter bores with clean engine oil. 2. Insert the
valve lifters into the lifter guides.
Align the flat area on the top of the lifter with the flat area in the lifter guide bore. Push the lifter
completely into the guide bore.
3. Install the valve lifters and guide to the engine block.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the valve lifter guide bolt (1).
- Tighten the valve lifter guide bolt (1) to 12 Nm (106 inch lbs.).
5. Install the cylinder head and gasket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Push Rod >
Component Information > Service and Repair
Push Rod: Service and Repair
Valve Rocker Arm and Push Rod Replacement
Removal Procedure
1. Remove the valve rocker arm cover.
Important: Place the valve rocker arms, pushrods, and pivot support, in a rack so that the can be
installed in the same location from which they were removed.
2. Remove the valve rocker arm bolts. 3. Remove the valve rocker arms.
4. Remove the valve rocker arm pivot support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Push Rod >
Component Information > Service and Repair > Page 3384
5. Remove the pushrods. 6. Clean and inspect the valve rocker arms and pushrods.
Installation Procedure
Important: When reusing the valve train components, always install the components to the original
location and position.
Valve lash is net build, no valve adjustment is required. 1. Lubricate the valve rocker arms and
pushrods with clean engine oil. 2. Lubricate the flange of the valve rocker arm bolts with clean
engine oil. Lubricate the flange or washer surface of the bolt that will contact the
valve rocker arm.
3. Install the valve rocker arm pivot support.
Important: Make sure that the pushrods seat properly to the valve lifter sockets.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Push Rod >
Component Information > Service and Repair > Page 3385
4. Install the pushrods.
Important: Make sure that the pushrods seat properly to the ends of the rocker arms. DO NOT
tighten the rocker arm bolts at this time.
5. Install the rocker arms and bolts.
6. Rotate the crankshaft until the number one piston is at top dead center (TDC) of the
compression stroke. In this position, cylinder number one
rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The
engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5 and 7 are the left bank. Cylinder 2,4,6 and 8
are the right bank.
Notice: Refer to Fastener Notice in Service Precautions.
7. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
- Tighten the cylinders 1,2,7 and 8 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 1,3,4 and 5 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
8. Rotate the crankshaft 360 degrees. 9. Tighten the following valve rocker arm bolts:
- Tighten the cylinders 3, 4, 5 and 6 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 2, 6, 7 and 8 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
10. Install the valve rocker arm cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Customer Interest for Rocker Arm Assembly: >
02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change
Rocker Arm Assembly: Customer Interest Engine - Needle Bearings Found Upon Oil Change
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-029
Date: September, 2002
INFORMATION
Subject: Needle Bearings Found in Oil Pan (Replace Rocker Arms)
Models:
1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird 2002 Cadillac Escalade,
Escalade EXT 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Suburban, Tahoe 2002
Chevrolet Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL 2003 HUMMER
H2 with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, G, S, U - RPOs LR4, LM7, LS1, L56, L04,
L09)
Condition
Some customers may comment or technicians may notice needle bearings being found during an
engine oil change. The bearings may be found in either the drain pan used or on the magnetic oil
pan drain plug.
Cause
One or more rocker arms may have experienced a bearing failure.
Correction
1. Inspect all of the rocker arms for bearing retainer cap failure. If one or more defective rocker
arms are found, replace all 16 rocker arms. Refer to the Engine Mechanical sub-section in the
appropriate Service Manual.
2. If no condition with the rocker arms is found, refer to the service history for previous rocker arm
repair. If previous rocker arm repair was made, then the engine may not have been thoroughly
cleaned of loose roller bearings. If no previous rocker arm repair was made, then look for another
condition.
3. Remove the oil pan and clean out any additional bearings found within the oil pan. Refer to the
Engine Mechanical sub-section in the appropriate Service Manual.
4. Install the oil pan. Refer to the Engine Mechanical sub-section in the appropriate Service
Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Customer Interest for Rocker Arm Assembly: >
02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change > Page 3394
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Rocker Arm
Assembly: > 02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change
Rocker Arm Assembly: All Technical Service Bulletins Engine - Needle Bearings Found Upon Oil
Change
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-029
Date: September, 2002
INFORMATION
Subject: Needle Bearings Found in Oil Pan (Replace Rocker Arms)
Models:
1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird 2002 Cadillac Escalade,
Escalade EXT 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Suburban, Tahoe 2002
Chevrolet Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL 2003 HUMMER
H2 with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, G, S, U - RPOs LR4, LM7, LS1, L56, L04,
L09)
Condition
Some customers may comment or technicians may notice needle bearings being found during an
engine oil change. The bearings may be found in either the drain pan used or on the magnetic oil
pan drain plug.
Cause
One or more rocker arms may have experienced a bearing failure.
Correction
1. Inspect all of the rocker arms for bearing retainer cap failure. If one or more defective rocker
arms are found, replace all 16 rocker arms. Refer to the Engine Mechanical sub-section in the
appropriate Service Manual.
2. If no condition with the rocker arms is found, refer to the service history for previous rocker arm
repair. If previous rocker arm repair was made, then the engine may not have been thoroughly
cleaned of loose roller bearings. If no previous rocker arm repair was made, then look for another
condition.
3. Remove the oil pan and clean out any additional bearings found within the oil pan. Refer to the
Engine Mechanical sub-section in the appropriate Service Manual.
4. Install the oil pan. Refer to the Engine Mechanical sub-section in the appropriate Service
Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Rocker Arm
Assembly: > 02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change > Page 3400
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Page 3401
Rocker Arm Assembly: Specifications
Valve Rocker Arm Bolt ........................................................................................................................
.................................................... 30 Nm (22 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Page 3402
Rocker Arm Assembly: Service and Repair
Valve Rocker Arm and Push Rod Replacement
Removal Procedure
1. Remove the valve rocker arm cover.
Important: Place the valve rocker arms, pushrods, and pivot support, in a rack so that the can be
installed in the same location from which they were removed.
2. Remove the valve rocker arm bolts. 3. Remove the valve rocker arms.
4. Remove the valve rocker arm pivot support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Page 3403
5. Remove the pushrods. 6. Clean and inspect the valve rocker arms and pushrods.
Installation Procedure
Important: When reusing the valve train components, always install the components to the original
location and position.
Valve lash is net build, no valve adjustment is required. 1. Lubricate the valve rocker arms and
pushrods with clean engine oil. 2. Lubricate the flange of the valve rocker arm bolts with clean
engine oil. Lubricate the flange or washer surface of the bolt that will contact the
valve rocker arm.
3. Install the valve rocker arm pivot support.
Important: Make sure that the pushrods seat properly to the valve lifter sockets.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Camshaft, Lifters and Push Rods > Rocker Arm
Assembly > Component Information > Technical Service Bulletins > Page 3404
4. Install the pushrods.
Important: Make sure that the pushrods seat properly to the ends of the rocker arms. DO NOT
tighten the rocker arm bolts at this time.
5. Install the rocker arms and bolts.
6. Rotate the crankshaft until the number one piston is at top dead center (TDC) of the
compression stroke. In this position, cylinder number one
rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The
engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5 and 7 are the left bank. Cylinder 2,4,6 and 8
are the right bank.
Notice: Refer to Fastener Notice in Service Precautions.
7. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
- Tighten the cylinders 1,2,7 and 8 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 1,3,4 and 5 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
8. Rotate the crankshaft 360 degrees. 9. Tighten the following valve rocker arm bolts:
- Tighten the cylinders 3, 4, 5 and 6 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 2, 6, 7 and 8 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
10. Install the valve rocker arm cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Connecting Rod
Bearing > Component Information > Specifications
Connecting Rod Bearing: Specifications
Connecting Rod Connecting Rod Bearing Bore Diameter
................................................................................................................... 56.505-56.525 mm
(2.224-2.225 inch) Connecting Rod Bearing Bore Out-of-Round
......................................................................................................... 0.004-0.008 mm
(0.00015-0.0003 inch) Connecting Rod Bearing Clearance (Production)
.................................................................................................... 0.023-0.065 mm. (0.0009-0.0025
inch) Connecting Rod Bearing Clearance (Service Limit)
................................................................................................... 0.023-0.076 mm (0.0009-0.003
inch) Connecting Rod Side Clearance
........................................................................................................................................ 0.11-0.51
mm (0.0043-0.02 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Connecting Rod,
Engine > Component Information > Technical Service Bulletins > Engine - Revised Connecting Rod Bolt Torque
Connecting Rod: Technical Service Bulletins Engine - Revised Connecting Rod Bolt Torque
Bulletin No.: 07-06-01-002
Date: March 05, 2007
INFORMATION
Subject: Information on Revised Connecting Rod Bolt Torque for Small Block GEN III and GEN IV
Vortec(TM) V8 Engines
Models
A new connecting rod bolt torque specification was introduced to the GEN III and GEN IV
Vortec(TM) small block V8 engines. The connecting rod bolts should continue to be tightened using
two passes. The second pass value has been increased from 75 degrees to 85 degrees.
Install the connecting rod bolts and tighten. Refer to Piston, Connecting Rod, and Bearing
Installation in SI.
Tighten
Tighten the connecting rod bolts a first pass to 20 N.m (15 lb ft).
Tighten the connecting rod bolts a final pass to 85 degrees using the J 45059 Angle Meter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Connecting Rod,
Engine > Component Information > Technical Service Bulletins > Engine - Revised Connecting Rod Bolt Torque > Page
3413
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Connecting Rod,
Engine > Component Information > Technical Service Bulletins > Page 3414
Connecting Rod: Specifications
Connecting Rod Connecting Rod Bearing Bore Diameter
................................................................................................................... 56.505-56.525 mm
(2.224-2.225 inch) Connecting Rod Bearing Bore Out-of-Round
......................................................................................................... 0.004-0.008 mm
(0.00015-0.0003 inch) Connecting Rod Bearing Clearance (Production)
.................................................................................................... 0.023-0.065 mm. (0.0009-0.0025
inch) Connecting Rod Bearing Clearance (Service Limit)
................................................................................................... 0.023-0.076 mm (0.0009-0.003
inch) Connecting Rod Side Clearance
........................................................................................................................................ 0.11-0.51
mm (0.0043-0.02 inch)
Connecting Rod Bolts-Early Design (First Pass)
...................................................................................................................................... 20 Nm (15 ft.
lbs.) Connecting Rod Bolts-Early Design (Final Pass)
................................................................................................................................................. 85
degrees Connecting Rod Bolts-Later Design (First Pass)
...................................................................................................................................... 20 Nm (15 ft.
lbs.) Connecting Rod Bolts-Later Design (Final Pass)
.................................................................................................................................................. 85
degrees
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Coolant Drain Plug,
Cylinder Block > Component Information > Specifications
Coolant Drain Plug: Specifications
Engine Block Coolant Drain Plugs
...........................................................................................................................................................
60 Nm (44 ft. lbs.) Cylinder Head Coolant Plug ...................................................................................
.................................................................................. 20 Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Main
Bearing > Component Information > Specifications > Engine Mechanical Specifications - (Unit Repair)
Crankshaft Main Bearing: Specifications Engine Mechanical Specifications - (Unit Repair)
Crankshaft
Bearing Clearance (Production)
................................................................................................................................ 0.020-0.052 mm
(0.0008-0.0021 inch) Bearing Clearance (Service)
...................................................................................................................................... 0.020-0.065
mm (0.0008-0.0025 inch) Connecting Rod Journal Diameter (Production)
........................................................................................................... 53.318-53.338 mm (2.099-2.1
inch) Connecting Rod Journal Diameter (Service Limit)
................................................................................. 53.308 mm (Minimum) (2.0987 inch (Minimum))
Connecting Rod Journal Taper (Production) ............... 0.005 mm (Maximum for one half of the
Journal Length (0.0002 inch (Maximum for one half of
the Journal Length))
Connecting Rod Journal Taper (Service Limit)
.......................................................................................... 0.02 mm (Maximum) 0.00078 inch
(Maximum) Connecting Rod Journal Out-of-Round (Production)
...................................................................................................................... 0.005 mm (0.0002 inch)
Connecting Rod Journal Out-of-Round (Service Limit)
.................................................................................................................... 0.01 mm (0.0004 inch)
End Play ..............................................................................................................................................
............................ 0.04-0.2 mm (0.0015-0.0078 inch) Main Journal Diameter (Production)
....................................................................................................................... 64.993-65.007 mm
(2.558-2.5593 inch) Main Journal Diameter (Service Limit)
..................................................................................................... 64.993 mm (Minimum) (2.558 inch
(Minimum)) Main Journal Out-of-Round (Production)
........................................................................................................................................ 0.003 mm
(0.0001 inch) Main Journal Out-of-Round (Service Limit)
................................................................................................................................... 0.008 mm
(0.0003 inch) Main Journal Taper (Production)
.......................................................................................................................................................
0.01 mm (0.0004 inch) Main Journal Taper (Service Limit)
................................................................................................................................................ 0.02
mm (0.00078 inch) Reluctor Ring Runout (Measured 1.0 mm (0.04 inch) Below the Tooth
Diameter) ...................................... 0.7 mm (Maximum) (0.028 inch (Maximum)) Runout (at Rear
Flange) ............................................................................................................................... 0.05 mm
(Maximum) (0.002 inch (Maximum)) Thrust Wall Runout ....................................................................
....................................................................................................... 0.025 mm (0.001 inch) Thrust
Wall Width (Production)
................................................................................................................................. 26.14-26.22 mm
(1.029-1.0315 inch) Thrust Wall Width (Service)
...................................................................................................................... 26.2 mm (Maximum)
(1.0315 inch (Maximum))
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Main
Bearing > Component Information > Specifications > Engine Mechanical Specifications - (Unit Repair) > Page 3422
Crankshaft Main Bearing: Specifications Fastener Tightening Specifications
Crankshaft Main Bearing Crankshaft Bearing Cap Bolts (Inner Bolts-First Pass in Sequence)
........................................................................................................ 20 Nm (15 ft. lbs.) Crankshaft
Bearing Cap Bolts (Inner Bolts-Final Pass in Sequence)
.................................................................................................................... 80 degrees Crankshaft
Bearing Cap Bolts (Outer Bolts-First Pass in Sequence)
........................................................................................................ 20 Nm (15 ft. lbs.) Crankshaft
Bearing Cap Bolts (Outer Bolts-Final Pass in Sequence)
................................................................................................................... 51 degrees Crankshaft
Bearing Cap Side Bolts
..........................................................................................................................................................
25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Seal
Retainer > Component Information > Specifications
Crankshaft Seal Retainer: Specifications
Engine Rear Cover Bolt .......................................................................................................................
..................................................... 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Seal
Retainer > Component Information > Specifications > Page 3426
Crankshaft Seal Retainer: Service and Repair
Engine Rear Cover Replacement
- Tools Required -
J41476 Front and Rear Cover Alignment (at crankshaft seal area)
Removal Procedure
1. Remove the engine flywheel.
2. Remove the oil pan-to-rear cover bolts (1).
3. Remove the rear cover bolts. 4. Remove the rear cover and gasket. 5. Discard the rear cover
gasket. 6. Clean and inspect the rear cover.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Seal
Retainer > Component Information > Specifications > Page 3427
Important: Do not reuse the crankshaft oil seal or rear cover gasket.
- Do not apply any type of sealant to the rear cover gasket (unless specified).
- The special tool in this procedure is used to properly center the crankshaft rear oil seal.
- The crankshaft rear oil seal will be installed after the rear cover has been installed and aligned.
Install the rear cover without the crankshaft oil seal. All gasket surfaces should be free of oil or other foreign material during assembly.
- The crankshaft rear oil seal MUST be centered in relation to the crankshaft.
- An improperly aligned rear cover may cause premature rear oil seal wear and/or engine assembly
oil leaks.
1. Apply a 5 mm (0.20 inch) bead of sealant GM U.S. P/N 12378190, or equivalent 20 mm (0.80
inch) long to the oil pan to engine block junction.
2. Install the rear cover gasket and cover. 3. Install the rear cover bolts until snug. Do not
overtighten.
4. Install the oil pan-to-rear cover bolts (1) until snug. Do not overtighten.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft Seal
Retainer > Component Information > Specifications > Page 3428
5. Rotate the crankshaft until two opposing flywheel bolt holes are parallel to the oil pan surface.
Important: The tapered legs of the alignment tool must enter the rear cover oil seal bore.
6. Install the J 41476 and bolts onto the rear of the crankshaft.
Notice: Refer to Fastener Notice in Service Precautions.
7. Tighten the J41476 mounting bolts until snug. Do not overtighten.
7.1. Tighten the oil pan-to-rear cover bolts to 12 Nm (106 inch lbs.).
7.2. Tighten the engine rear cover bolts to 25Nm (18lbft).
8. Remove the J41476. 9. Install a NEW crankshaft rear oil seal.
10. Install the engine flywheel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft, Engine >
Component Information > Specifications > Engine Mechanical Specifications (Unit Repair)
Crankshaft: Specifications Engine Mechanical Specifications (Unit Repair)
Crankshaft
Bearing Clearance (Production)
................................................................................................................................ 0.020-0.052 mm
(0.0008-0.0021 inch) Bearing Clearance (Service)
...................................................................................................................................... 0.020-0.065
mm (0.0008-0.0025 inch) Connecting Rod Journal Diameter (Production)
........................................................................................................... 53.318-53.338 mm (2.099-2.1
inch) Connecting Rod Journal Diameter (Service Limit)
................................................................................. 53.308 mm (Minimum) (2.0987 inch (Minimum))
Connecting Rod Journal Taper (Production) ........... 0.005 mm (Maximum for one half of the
Journal Length (0.0002 inch (Maximum for one half of the
Journal Length))
Connecting Rod Journal Taper (Service Limit)
....................................................................................... 0.02 mm (Maximum) (0.00078 inch
(Maximum)) Connecting Rod Journal Out-of-Round (Production)
...................................................................................................................... 0.005 mm (0.0002 inch)
Connecting Rod Journal Out-of-Round (Service Limit)
.................................................................................................................... 0.01 mm (0.0004 inch)
End Play ..............................................................................................................................................
............................ 0.04-0.2 mm (0.0015-0.0078 inch) Main Journal Diameter (Production)
....................................................................................................................... 64.993-65.007 mm
(2.558-2.5593 inch) Main Journal Diameter (Service Limit)
..................................................................................................... 64.993 mm (Minimum) (2.558 inch
(Minimum)) Main Journal Out-of-Round (Production)
........................................................................................................................................ 0.003 mm
(0.0001 inch) Main Journal Out-of-Round (Service Limit)
................................................................................................................................... 0.008 mm
(0.0003 inch) Main Journal Taper (Production)
.......................................................................................................................................................
0.01 mm (0.0004 inch) Main Journal Taper (Service Limit)
................................................................................................................................................ 0.02
mm (0.00078 inch) Reluctor Ring Runout (Measured 1.0 mm (0.04 inch) Below the Tooth
Diameter) ...................................... 0.7 mm (Maximum) (0.028 inch (Maximum)) Runout (at Rear
Flange) ............................................................................................................................... 0.05 mm
(Maximum) (0.002 inch (Maximum)) Thrust Wall Runout ....................................................................
....................................................................................................... 0.025 mm (0.001 inch) Thrust
Wall Width (Production)
................................................................................................................................. 26.14-26.22 mm
(1.029-1.0315 inch) Thrust Wall Width (Service)
...................................................................................................................... 26.2 mm (Maximum)
(1.0315 inch (Maximum))
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Crankshaft, Engine >
Component Information > Specifications > Engine Mechanical Specifications (Unit Repair) > Page 3433
Crankshaft: Specifications Fastener Tightening Specifications
Crankshaft Oil Deflector Nut ................................................................................................................
.................................................... 25 Nm (18 ft. lbs.) Crossbar Bolt ....................................................
...................................................................................................................................... 100 Nm (74 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Specifications
Engine Block Heater: Specifications
Engine Block Heater ............................................................................................................................
..................................................... 40 Nm (30 ft. lbs.) Coolant Heater Cord Bolt .................................
....................................................................................................................................... 8 Nm (71
inch lbs.) Coolant Heater .....................................................................................................................
..................................................................... 50 Nm (37 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Service and Repair > Coolant Heater Cord Replacement
Engine Block Heater: Service and Repair Coolant Heater Cord Replacement
Coolant Heater Cord Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Disconnect the coolant heater electrical connector (2).
3. Remove the coolant heater cord retainer and bolts. 4. Remove the coolant heater cord.
Installation Procedure
Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route
the cord to the left front of the engine compartment securing with tie straps as necessary to prevent
damage.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Service and Repair > Coolant Heater Cord Replacement > Page 3439
1. Install the coolant heater cord.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the coolant heater cord bolts and retainer.
- Tighten the coolant heater cord bolts to 8 Nm (71 inch lbs.).
3. Connect the coolant heater electrical connector (2). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Service and Repair > Coolant Heater Cord Replacement > Page 3440
Engine Block Heater: Service and Repair Coolant Heater Replacement
Coolant Heater Replacement (4.8L, 5.31-, and 6.0L Engines)
Removal Procedure
1. Drain the cooling system/engine block. Refer to Draining and Filling Cooling System. 2. Raise
and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information. 3.
Remove the oil pan skid plate bolts and plate.
4. Remove the oil cooler hose bracket bolt (1). 5. Remove the oil cooler hose adapter bolts (2). 6.
Remove and discard the oil cooler hose adapter gasket. 7. Position the oil cooler hose adapter end
out of the way.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Service and Repair > Coolant Heater Cord Replacement > Page 3441
8. Disconnect the coolant heater electrical connector (2).
Important: Do not score the surface of the engine block hole when removing the coolant heater.
9. Remove the coolant heater from the engine block.
10. Remove any burrs, sealer, or other rough spots.
Installation Procedure
1. If reusing the old coolant heater, apply thread sealant GM P/N 12346004 (Canadian P/N
10953480) or equivalent to the threads.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the coolant heater to the engine block.
- Tighten the coolant heater to 50 Nm (37 ft. lbs.).
Notice: The heater cord must not touch the engine, hot pipes, manifold, or any moving parts. Route
the cord to the left front of the engine compartment securing with tie straps as necessary to prevent
damage.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Block Heater >
Component Information > Service and Repair > Coolant Heater Cord Replacement > Page 3442
3. Connect the coolant heater electrical connector (2).
4. Position the oil cooler hose adapter end. 5. Install a NEW oil cooler hose adapter gasket. 6.
Install the oil cooler hose adapter bolts (2).
- Tighten the oil cooler hose adapter bolts to 12 Nm (106 inch lbs.).
7. Install the oil cooler hose bracket bolt (1).
- Tighten the oil cooler hose bracket bolt to 25 Nm (118 ft. lbs.).
8. Install the oil pan skid plate and bolts.
- Tighten the oil pan skid plate bolts to 20 Nm (15 ft. lbs.).
9. Lower the vehicle.
10. Fill the cooling system/engine block. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Valley Cover >
Component Information > Specifications
Engine Valley Cover: Specifications
Engine Valley Cover Bolt .....................................................................................................................
.................................................... 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Valley Cover >
Component Information > Specifications > Page 3446
Engine Valley Cover: Service and Repair
Engine Valley Cover Replacement
Removal Procedure
1. Remove the intake manifold. 2. Gently pry up the rubber covers. 3. Disconnect the knock sensor
electrical connectors.
4. Remove the knock sensors.
5. Remove the engine valley cover bolts. 6. Remove the engine valley cover and gasket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Valley Cover >
Component Information > Specifications > Page 3447
7. Discard the old gasket.
8. Remove the knock sensor oil seals (1) from the cover (2). 9. Clean and inspect the engine valley
cover.
Installation Procedure
Important: All gasket surfaces should be free of oil or other foreign material during assembly.
1. Lubricate the NEW knock sensor seals (1) with clean engine oil. 2. Install the knock sensor oil
seals (1) into the engine valley cover (2).
3. Install the engine valley cover and a NEW gasket onto the engine block.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the engine valley cover bolts.
- Tighten the bolts to 25 Nm (18 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Engine Valley Cover >
Component Information > Specifications > Page 3448
5. Install the knock sensors.
- Tighten the sensors to 20 Nm (15 ft. lbs.).
6. Connect the knock sensor electrical connectors. 7. Push down on the rubber covers. 8. Install
the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Harmonic Balancer Crankshaft Pulley > Component Information > Specifications
Harmonic Balancer - Crankshaft Pulley: Specifications
Crankshaft Balancer Bolt
Installation Pass-to Ensure the Balancer is Completely Installed
......................................................................................................... 330 Nm (240 ft. lbs.) First Pass
Install a NEW Bolt After the Installation Pass and Tighten as Described in the First and Final
Passes ................................... 50 Nm (37 ft. lbs.) Final Pass .............................................................
............................................................................................................................................... 140
degrees
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Harmonic Balancer Crankshaft Pulley > Component Information > Specifications > Page 3452
Harmonic Balancer - Crankshaft Pulley: Service and Repair
Crankshaft Balancer Replacement
- Tools Required J 41816 Crankshaft Balancer Remover
- J 41816-2 Crankshaft End Protector
- J 42386-A Flywheel Holding Tool
- J 41665 Crankshaft Balancer and Sprocket Installer
- J 36660-A Torque Angle Meter
Removal Procedure
1. Remove the air conditioning (A/C) drive belt, if equipped. 2. Remove the accessory drive belt, if
not equipped with A/C. 3. Remove the fan shroud - lower. 4. Remove the starter motor.
Important: Make sure that the teeth of the J 42386-A mesh with the teeth of the engine flywheel.
- The crankshaft balancer is balanced as an individual component. It is not necessary to mark the
balancer prior to removal.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the J 42386-A and bolts.
Use one M10-1.5 x 120 mm and one M10-1.5 x 45 mm bolt for proper tool operation. Tighten the J 42386-A bolts to 50 Nm (37 ft. lbs.).
6. Remove the crankshaft balancer bolt. Do not discard the crankshaft balancer bolt. The balancer
bolt will be used during the balancer installation
procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Harmonic Balancer Crankshaft Pulley > Component Information > Specifications > Page 3453
7. Use the J 41816 and J 41816-2 in order to remove the crankshaft balancer. 8. Remove the
J41816 and the J41816-2 from the crankshaft balancer. 9. Clean and inspect the crankshaft
balancer.
Installation Procedure
Important: Make sure that the teeth of J 42386-A mesh with the teeth of the engine flywheel.
- The used crankshaft balancer bolt will be used only during the first pass of the balancer
installation procedure. Install a NEW bolt and tighten as described in the second, third and forth
passes of the balancer bolt tightening procedure.
- The crankshaft balancer installation and bolt tightening involves a four stage tightening process.
The first pass ensures that the balancer is installed completely onto the crankshaft. The second,
third, and forth passes tighten the new bolt to the proper torque.
Important: The balancer should be positioned onto the end of the crankshaft as straight as possible
prior to tool installation.
1. Install the crankshaft balancer onto the end of the crankshaft.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Harmonic Balancer Crankshaft Pulley > Component Information > Specifications > Page 3454
2. Use the J 41665 in order to install the crankshaft balancer.
2.1. Assemble the threaded rod, nut, washer and installer. Insert the smaller end of the installer into
the front of the balancer.
2.2. Use a wrench and hold the hex end of the threaded rod.
2.3. Use a second wrench and rotate the installation tool nut clockwise until the balancer is started
onto the crankshaft.
2.4. Remove the tool and reverse the installation tool. Position the larger end of the installer against
the front of the balancer.
2.5. Use a wrench and hold the hex end of the threaded rod.
2.6. Use a second wrench and rotate the installation tool nut clockwise until the balancer is
installed onto the crankshaft. - Remove the balancer installation tool.
3. Install the used crankshaft balancer bolt.
- Tighten the USED crankshaft balancer bolt to 330 Nm (240 ft. lbs.).
4. Remove the used crankshaft balancer bolt.
Important: The nose of the crankshaft should be recessed 2.4 - 4.48 mm (0.094 - 0.176 inch) into
the balancer bore.
5. Measure for a correctly installed balancer.
If the balancer is not installed to the proper dimensions, install the J 41665 and repeat the
installation procedure.
6. Install a NEW crankshaft balancer bolt.
6.1. Tighten the crankshaft balancer bolt a first pass to 50 Nm (37 ft. lbs.).
6.2. Tighten the crankshaft balancer bolt a second pass to 140 degrees using J 36660-A.
7. Remove the J 42386-A and bolts. 8. Install the starter motor. 9. Install the fan shroud - lower.
10. Install the accessory drive belt (if not equipped with A/C). 11. Install the A/C drive belt (if
equipped). 12. Perform the crankshaft position (CKP) system variation learn procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Piston, Engine >
Component Information > Specifications
Piston: Specifications
Piston
Outside Diameter (at Size Point)
............................................................................................................................... 95.962-95.980
mm (3.778-3.779 inch) Piston to Bore Clearance (Production)
...................................................................................................................... 0.020-0.061 mm
(0.0008-0.0024 inch) Piston to Bore Clearance (Service Limit)
....................................................................... 0.0.020-0.086 mm (Maximum) (0.0008-0.0034 inch
(Maximum))
Piston Pin
Clearance to Piston Bore (Production)
.................................................................................................................. 0.007-0.020 mm
(0.00027-0.00078 inch) Pin Clearance to Piston Bore (Service Limit)
............................................................... 0.007-0.021 mm (Maximum) (0.00027-0.00082 inch
(Maximum)) Diameter ..........................................................................................................................
.......................................... 23.997-24.0 mm (0.9447-0.9448 inch) Fit in Connecting Rod
.............................................................................................. 0.020-0 043 mm (Interference)
(0.00078-0.00169 inch (Interference))
Piston Rings
Compression Ring End Gap (Production-Top) (Measured in Cylinder Bore)
.................................................................. 0.23-0.44 mm (0.009-0.017 inch) Compression Ring End
Gap (Production-2nd) (Measured in Cylinder Bore) ...............................................................
0.44-0.70 mm (0.0173-0.0275 inch) Oil Ring End Gap (Production) (Measured in Cylinder Bore)
........................................................................................ 0.18-0.75 mm (0.007-0.0295 inch)
Compression Ring End Gap (Service-Top) (Measured in Cylinder Bore) ..................................
0.23-0.50 mm (Maximum) (0.009-0.02 inch (Maximum)) Compression Ring End Gap
(Service-2nd)(Measured in Cylinder Bore) ................................. 0.44-0.76 mm (Maximum)
(0.0173-0.03 inch (Maximum)) Oil Ring End Gap-Service Limit (Measured in Cylinder Bore)
................................................ 0.18-0.81 mm (Maximum) (0.007-0.032 inch (Maximum))
Compression Ring Groove Clearance (Production-Top)
...................................................................................... 0.04-0.085 mm (0.00157-0.003346 inch)
Compression Ring Groove Clearance (Production-2nd)
........................................................................................... 0.04-0.078 mm (0.00157-0.0031 inch) Oil
Ring Groove Clearance (Production)
.................................................................................................................... 0.012-0.20 mm
(0.0005-0.0078 inch) Compression Ring Groove Clearance (Service-Top)
.................................................... 0.04-0.085 mm (Maximum) (0.00157-0.003346 inch (Maximum))
Compression Ring Groove Clearance (Service-2nd) ...........................................................
0.0-0.078 mm (Maximum) (0.00157-0.0031 inch (Maximum)) Oil Ring Groove Clearance (Service
Limit) ........................................................................ 0.012-0.20 mm (Maximum) (0.0005-0.0078
inch (Maximum))
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Piston Pin, Engine >
Component Information > Specifications
Piston Pin: Specifications
Piston Pin
Piston Pin Clearance to Piston Bore (Production)
................................................................................................. 0.007-0.020 mm (0.00027-0.00078
inch) Piston Pin Clearance to Piston Bore (Service Limit) .....................................................
0.007-0.021 mm (Maximum) (0.00027-0.00082 inch (Maximum)) Piston Pin Diameter
...................................................................................................................................................
23.997-24.0 mm (0.9447-0.9448 inch) Piston Pin Fit in Connecting Rod
............................................................................ 0.020-0 043 mm (Interference) (0.00078-0.00169
inch (Interference))
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Block Assembly > Piston Ring, Engine >
Component Information > Specifications
Piston Ring: Specifications
Piston Rings
Compression Ring End Gap (Production-Top) (Measured in Cylinder Bore)
..................................................................... 0.23-0.44 mm 0.009-0.017 inch Compression Ring End
Gap (Production-2nd) (Measured in Cylinder Bore) .................................................................
0.44-0.70 mm 0.0173-0.0275 inch Oil Ring End Gap (Production) (Measured in Cylinder Bore)
.......................................................................................... 0.18-0.75 mm 0.007-0.0295 inch
Compression Ring End Gap (Service-Top) (Measured in Cylinder Bore) ..................................
0.23-0.50 mm (Maximum) 0.009-0.02 inch (Maximum) Compression Ring End Gap
(Production-Top) (Measured in Cylinder Bore) .................................................................. 0.23-0.44
mm (0.009-0.017 inch) Compression Ring End Gap (Production-2nd) (Measured in Cylinder Bore)
............................................................... 0.44-0.70 mm (0.0173-0.0275 inch) Oil Ring End Gap
(Production) (Measured in Cylinder Bore) ........................................................................................
0.18-0.75 mm (0.007-0.0295 inch) Compression Ring End Gap (Service-Top) (Measured in
Cylinder Bore) .................................. 0.23-0.50 mm (Maximum) (0.009-0.02 inch (Maximum))
Compression Ring End Gap (Service-2nd)(Measured in Cylinder Bore) .................................
0.44-0.76 mm (Maximum) (0.0173-0.03 inch (Maximum)) Oil Ring End Gap-Service Limit
(Measured in Cylinder Bore) ................................................ 0.18-0.81 mm (Maximum) (0.007-0.032
inch (Maximum)) Compression Ring Groove Clearance (Production-Top)
...................................................................................... 0.04-0.085 mm (0.00157-0.003346 inch)
Compression Ring Groove Clearance (Production-2nd)
........................................................................................... 0.04-0.078 mm (0.00157-0.0031 inch) Oil
Ring Groove Clearance (Production)
.................................................................................................................... 0.012-0.20 mm
(0.0005-0.0078 inch) Compression Ring Groove Clearance (Service-Top)
.................................................... 0.04-0.085 mm (Maximum) (0.00157-0.003346 inch (Maximum))
Compression Ring Groove Clearance (Service-2nd) ...........................................................
0.0-0.078 mm (Maximum) (0.00157-0.0031 inch (Maximum)) Oil Ring Groove Clearance (Service
Limit) ........................................................................ 0.012-0.20 mm (Maximum) (0.0005-0.0078
inch (Maximum))
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Clearance >
System Information > Specifications
Valve Clearance: Specifications
The manufacturer indicates that this vehicle has hydraulic lifters or adjusters and therefore does
not require adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Fuel Pressure Release
> System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Fuel Pressure Release
> System Information > Service and Repair > Fuel Pressure Gage Installation and Removal > Page 3472
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Customer Interest for Rocker Arm Assembly: > 02-06-01-029 >
Sep > 02 > Engine - Needle Bearings Found Upon Oil Change
Rocker Arm Assembly: Customer Interest Engine - Needle Bearings Found Upon Oil Change
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-029
Date: September, 2002
INFORMATION
Subject: Needle Bearings Found in Oil Pan (Replace Rocker Arms)
Models:
1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird 2002 Cadillac Escalade,
Escalade EXT 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Suburban, Tahoe 2002
Chevrolet Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL 2003 HUMMER
H2 with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, G, S, U - RPOs LR4, LM7, LS1, L56, L04,
L09)
Condition
Some customers may comment or technicians may notice needle bearings being found during an
engine oil change. The bearings may be found in either the drain pan used or on the magnetic oil
pan drain plug.
Cause
One or more rocker arms may have experienced a bearing failure.
Correction
1. Inspect all of the rocker arms for bearing retainer cap failure. If one or more defective rocker
arms are found, replace all 16 rocker arms. Refer to the Engine Mechanical sub-section in the
appropriate Service Manual.
2. If no condition with the rocker arms is found, refer to the service history for previous rocker arm
repair. If previous rocker arm repair was made, then the engine may not have been thoroughly
cleaned of loose roller bearings. If no previous rocker arm repair was made, then look for another
condition.
3. Remove the oil pan and clean out any additional bearings found within the oil pan. Refer to the
Engine Mechanical sub-section in the appropriate Service Manual.
4. Install the oil pan. Refer to the Engine Mechanical sub-section in the appropriate Service
Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Customer Interest for Rocker Arm Assembly: > 02-06-01-029 >
Sep > 02 > Engine - Needle Bearings Found Upon Oil Change > Page 3481
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Rocker Arm Assembly: >
02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change
Rocker Arm Assembly: All Technical Service Bulletins Engine - Needle Bearings Found Upon Oil
Change
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-029
Date: September, 2002
INFORMATION
Subject: Needle Bearings Found in Oil Pan (Replace Rocker Arms)
Models:
1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird 2002 Cadillac Escalade,
Escalade EXT 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Suburban, Tahoe 2002
Chevrolet Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL 2003 HUMMER
H2 with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, G, S, U - RPOs LR4, LM7, LS1, L56, L04,
L09)
Condition
Some customers may comment or technicians may notice needle bearings being found during an
engine oil change. The bearings may be found in either the drain pan used or on the magnetic oil
pan drain plug.
Cause
One or more rocker arms may have experienced a bearing failure.
Correction
1. Inspect all of the rocker arms for bearing retainer cap failure. If one or more defective rocker
arms are found, replace all 16 rocker arms. Refer to the Engine Mechanical sub-section in the
appropriate Service Manual.
2. If no condition with the rocker arms is found, refer to the service history for previous rocker arm
repair. If previous rocker arm repair was made, then the engine may not have been thoroughly
cleaned of loose roller bearings. If no previous rocker arm repair was made, then look for another
condition.
3. Remove the oil pan and clean out any additional bearings found within the oil pan. Refer to the
Engine Mechanical sub-section in the appropriate Service Manual.
4. Install the oil pan. Refer to the Engine Mechanical sub-section in the appropriate Service
Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Rocker Arm Assembly: >
02-06-01-029 > Sep > 02 > Engine - Needle Bearings Found Upon Oil Change > Page 3487
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Page 3488
Rocker Arm Assembly: Specifications
Valve Rocker Arm Bolt ........................................................................................................................
.................................................... 30 Nm (22 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Page 3489
Rocker Arm Assembly: Service and Repair
Valve Rocker Arm and Push Rod Replacement
Removal Procedure
1. Remove the valve rocker arm cover.
Important: Place the valve rocker arms, pushrods, and pivot support, in a rack so that the can be
installed in the same location from which they were removed.
2. Remove the valve rocker arm bolts. 3. Remove the valve rocker arms.
4. Remove the valve rocker arm pivot support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Page 3490
5. Remove the pushrods. 6. Clean and inspect the valve rocker arms and pushrods.
Installation Procedure
Important: When reusing the valve train components, always install the components to the original
location and position.
Valve lash is net build, no valve adjustment is required. 1. Lubricate the valve rocker arms and
pushrods with clean engine oil. 2. Lubricate the flange of the valve rocker arm bolts with clean
engine oil. Lubricate the flange or washer surface of the bolt that will contact the
valve rocker arm.
3. Install the valve rocker arm pivot support.
Important: Make sure that the pushrods seat properly to the valve lifter sockets.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Rocker Arm Assembly
> Component Information > Technical Service Bulletins > Page 3491
4. Install the pushrods.
Important: Make sure that the pushrods seat properly to the ends of the rocker arms. DO NOT
tighten the rocker arm bolts at this time.
5. Install the rocker arms and bolts.
6. Rotate the crankshaft until the number one piston is at top dead center (TDC) of the
compression stroke. In this position, cylinder number one
rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The
engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5 and 7 are the left bank. Cylinder 2,4,6 and 8
are the right bank.
Notice: Refer to Fastener Notice in Service Precautions.
7. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
- Tighten the cylinders 1,2,7 and 8 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 1,3,4 and 5 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
8. Rotate the crankshaft 360 degrees. 9. Tighten the following valve rocker arm bolts:
- Tighten the cylinders 3, 4, 5 and 6 exhaust valve rocker arm bolts to 30 Nm (22 ft. lbs.).
- Tighten the cylinders 2, 6, 7 and 8 intake valve rocker arm bolts to 30 Nm (22 ft. lbs.).
10. Install the valve rocker arm cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Specifications
Valve Cover: Specifications
Valve Rocker Cover Bolt .....................................................................................................................
............................................... 12 Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left)
Valve Cover: Service and Repair Valve Rocker Arm Cover Replacement (Left)
Valve Rocker Arm Cover Replacement - Left
Removal Procedure
1. Remove the engine sight shield, if required. 2. Remove the connector position assurance (CPA)
lock. 3. Disconnect the main electrical connector (2) feeding the ignition coils. 4. Remove the
harness clips (1). 5. Reposition the engine harness, if necessary. 6. Remove the spark plug wires
from the ignition coils.
- Twist each plug wire 1/2 turn.
- Pull only on the boot in order to remove the wire from the ignition coil.
7. Remove the ignition coil bracket studs from the rocker arm cover. 8. Remove the ignition coils
and bracket from the rocker arm cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3497
9. Remove the positive crankcase ventilation (PCV) hose from the rocker arm cover.
10. Remove the valve rocker arm cover bolts. 11. Remove the valve rocker arm cover.
12. Remove the gasket (1) from the rocker cover. 13. Discard the OLD gasket. 14. Clean and
inspect the rocker arm cover.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3498
Important: All gasket surfaces should be free of oil an/or other foreign material during assembly.
- DO NOT reuse the valve rocker arm cover gasket.
- The valve rocker arm cover bolt grommets may be reused.
- If the PCV valve grommet has been removed from the rocker cover, install a NEW grommet
during assembly.
1. Install a NEW rocker cover gasket (1) into the valve rocker cover lip.
2. Install the valve rocker arm cover onto the cylinder head. 3. Install new rocker arm cover
grommets, if necessary.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the rocker arm cover bolts.
- Tighten the bolts to 12 Nm (106 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3499
5. Install the PCV hose to the rocker arm cover.
6. Apply threadlock GM U.S. P/N 12345382, Canada P/N 10953489, or equivalent to the threads of
the bracket bolts. 7. Install the ignition coils and bracket to the rocker arm cover. 8. Install the
ignition coil bracket studs to the rocker arm cover.
- Tighten the studs to 12 Nm (106 inch lbs.).
9. Install the spark plug wires to the ignition coils.
10. Position the engine harness, if necessary. 11. Install the harness clips (1). 12. Connect the
main electrical connector (2) feeding the ignition coils. 13. Install the CPA lock. 14. Install the
engine sight shield, if required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3500
Valve Cover: Service and Repair Valve Rocker Arm Cover Replacement (Right)
Valve Rocker Arm Cover Replacement - Right
Removal Procedure
1. Remove the engine sight shield, if required. 2. Remove the connector position assurance (CPA)
lock. 3. Disconnect the main electrical connector (1) feeding the ignition coils. 4. Remove the
harness clips (2). 5. Reposition the engine harness, if necessary. 6. Remove the spark plug wires
from the ignition coils.
- Twist each plug wire 1/2 turn.
- Pull only on the boot in order to remove the wire from the ignition coil.
7. If equipped with the 4.8L, 5.3L, or 6.0L (LQ4) engine, perform the following:
7.1. Reposition the surge tank/heater hoses from the heater hose bracket.
7.2. Remove the heater hose bracket nut and bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3501
8. Remove the ignition coil bracket studs from the rocker arm cover. 9. Remove the ignition coils
and bracket from the rocker cover.
10. Remove the positive crankcase ventilation (PCV) hose from the throttle body and rocker cover.
11. Remove the valve rocker arm cover bolts. 12. Remove the valve rocker arm cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3502
13. Remove the gasket (1) from the rocker cover. 14. Discard the OLD gasket.
15. Remove the oil fill cap from the oil fill tube. 16. Remove the oil fill tube from the rocker cover, if
required. 17. Discard the oil fill tube. 18. Clean and inspect the rocker arm cover.
Installation Procedure
Important: All gasket surfaces should be free of oil or other foreign material during assembly.
- DO NOT reuse the valve rocker arm cover gasket.
- The valve rocker arm cover bolt grommets may be reused.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3503
- If the oil fill tube has been removed from the rocker arm cover, install a NEW fill tube during
assembly.
1. Lubricate the O-ring seal of the NEW oil fill tube with clean engine oil. 2. Insert the NEW oil fill
tube into the rocker arm cover. Rotate the tube clockwise until locked in the proper position. 3.
Install the oil fill cap into the tube. Rotate the cap clockwise until locked in the proper position.
4. Install a NEW rocker cover gasket (1) into the valve rocker cover lip.
5. Install the valve rocker arm cover onto the cylinder head.
6. Install new rocker arm cover grommets, if necessary.
Notice: Refer to Fastener Notice in Service Precautions.
7. Install the rocker arm cover bolts and grommets.
- Tighten the bolts to 12 Nm (106 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3504
8. Install the PCV hose to the throttle body and rocker cover.
9. Apply threadlock GM P/N 12345382, Canada PIN 10953489, or equivalent to the threads of the
bracket bolts.
10. Install the ignition coils and bracket to the rocker arm cover. 11. Install the ignition coil bracket
studs to the rocker cover.
- Tighten the studs to 12 Nm (106 inch lbs.).
12. If equipped with the 4.8L, 5.3L, or 6.0L (LQ4) engine, perform the following:
12.1. Install the heater hose bracket and nut. Tighten the nut to 9 Nm (80 inch lbs.).
12.2. Position the surge tank/heater hoses to the heater hose bracket.
13. Install the spark plug wires to the ignition coils. 14. Position the engine harness, if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Cover >
Component Information > Service and Repair > Valve Rocker Arm Cover Replacement (Left) > Page 3505
15. Install the harness clips (2). 16. Connect the main electrical connector (1) feeding the ignition
coils. 17. Install the CPA lock. 18. Install the engine sight shield, if required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Seat >
Component Information > Specifications
Valve Seat: Specifications
Valve Seat
Angle ...................................................................................................................................................
.................................................................. 46 degrees Runout
............................................................................................................................................................
0.05 mm (Maximum) 0.002 inch (Maximum) Width (Exhaust) ............................................................
......................................................................................................................... 1.78 mm (0.07 inch)
Width (Intake) ......................................................................................................................................
.................................................. 1.02 mm (0.04 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications
Valve Spring: Specifications
Valve Spring
Free Length .........................................................................................................................................
................................................... 52.9 mm (2.08 inch) Installed Height (Exhaust) ..............................
....................................................................................................................................... 45.75 mm
(1.8 inch) Installed Height (Intake) .......................................................................................................
................................................................. 45.75 mm (1.8 inch) Pressure (Closed)
...................................................................................................................................................... 340
N at 45.75 mm (76 lb. at 1.8 inch) Pressure (Open)
..................................................................................................................................................... 980
N at 33.55 mm (220 lb. at 1.32 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications > Page 3512
Valve Spring: Service and Repair
Valve Stem Oil Seal and Valve Spring Replacement
- Tools Required -
J 22794 Spark Plug Port Adapter
- J 38606 Valve Spring Compressor
- J 42078 Valve Stem Oil Seal Installer
Removal Procedure
1. Remove the valve rocker arm. 2. Disconnect the spark plug wire at the spark plug.
- Twist each plug wire boot 1/2 turn.
- Pull only on the boot in order to remove the wire from the spark plug.
Important: Remove the spark plugs from the cylinder head with the engine at room temperature.
3. Loosen the spark plug 1 or 2 turns. 4. Brush or air blast away any dirt or debris from around the
spark plug. 5. Remove the spark plug.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications > Page 3513
6. Install J 22794 into the spark plug hole. 7. Attach an air hose to J22794. 8. Apply compressed air
to J 22794 in order to hold the valves in place.
9. Use J 38606 in order to compress the valve spring.
10. Remove the valve stem keys (3). 11. Carefully release the valve spring tension.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications > Page 3514
12. Remove the J 38606. 13. Remove the valve spring cap (4). 14. Remove the valve spring (5).
Important: A second design valve stem oil seal and shim may be used on later engines. A separate
spring shim is not required with the second design seal and shim.
15. Remove the valve stem oil seal (6) (first design). 16. Remove the valve spring shim (7) (first
design). 17. Remove the valve stem oil seal and shim (2) (second design)
Installation Procedure
1. Clean the cylinder head valve spring seat and/or shim area. 2. Install the valve spring shim (7)
(first design). 3. Install the valve stem oil seal and shim (2) (second design). J42078 is not required
for installation of the second design seal and shim.
Important: The valve stem oil seal alignment and position on the valve guide is critical.
An improperly installed valve stem oil seal may lead to excessive oil consumption, increased
vehicle emissions, or component damage.
4. Install the valve stem oil seal (first design) onto the guide.
4.1. Lubricate the valve guide and valve stem oil seal with clean engine oil.
4.2. Install the valve stem oil seal (first design) onto the valve stem. Push the seal down until the
seal contacts the valve guide.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications > Page 3515
4.3. Use the J 42078 in order to install the valve stem oil seal. Push or lightly tap the tool until the
tool bottoms against the valve spring shim.
5. Measure the valve stem oil seals (first design) for the properly installed height. There should be
a 18.1 - 19.1 mm (0.712 - 0.752 inch) gap
between the top edge of the oil seal body and the valve spring shim surface.
6. Install the valve spring (5). 7. Install the valve spring cap (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve Spring >
Component Information > Specifications > Page 3516
8. Compress the valve spring using the J 38606. 9. Install the valve keys.
- Use grease in order to hold the valve keys in place.
- Make sure the keys seat properly in the groove of the valve stem.
- Carefully release the valve spring pressure, making sure the valve keys stay in place.
- Remove the J 38606.
- Tap the end of the valve stem with a plastic faced hammer to seat the keys (if necessary).
10. Remove J 22794 from the spark plug port.
Notice: Refer to Fastener Notice in Service Precautions.
11. Hand start the spark plug.
- Tighten the spark plug to 15 Nm (11 ft. lbs.).
12. Install the spark plug wires at the ignition coil. 13. Install the spark plug wire to the spark plug.
14. Inspect the wires for proper installation:
- Push sideways on each boot in order to check for proper installation.
- Reinstall any loose boot.
15. Install the valve rocker arm.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Cylinder Head Assembly > Valve, Intake/Exhaust
> Component Information > Specifications
Valve: Specifications
Valve System
Valve Face Angle ................................................................................................................................
.................................................................. 45 degrees Valve Guide Installed Height (Aluminum
Head-Measured from the Cylinder Head Spring Seat Surface to the Top of the Valve Guide) ...........
17.32 mm
(0.682 inch)
Valve Lash ...........................................................................................................................................
........................................... Net Lash-No Adjustment Valve Lift (Exhaust) .........................................
................................................................................................................................. 11.85 mm (0.466
inch) Valve Lift (Intake) ........................................................................................................................
....................................................... 11.6 mm (0.457 inch) Valve Lifter ................................................
.................................................................................................................................................
Hydraulic Roller Valve Margin .............................................................................................................
............................................................................ 1.25 mm (0.05 inch) Rocker Arm Ratio ..................
..............................................................................................................................................................
........................ 1.70:1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > Customer Interest: > 01-02-32-007 > Sep > 01 >
Accessory Drive Belt - Whining Type Noise
Drive Belt: Customer Interest Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics
Drive Belt: All Technical Service Bulletins Engine - Drive Belt Misalignment Diagnostics
INFORMATION
Bulletin No.: 08-06-01-008A
Date: July 27, 2009
Subject: Diagnosing Accessory Drive Belt / Serpentine Belt Noise and Availability and Use of
Kent-Moore EN-49228 Laser Alignment Tool - Drive Belt
Models:
2010 and Prior GM Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2,
H3 Vehicles 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add a model year and update the Tool Information.
Please discard Corporate Bulletin Number 08-06-01-008 (Section 06 - Engine).
Background
Several aftermarket companies offer laser alignment tools for accessory drive systems that can be
very helpful in eliminating drive belt noise as a result of misaligned pulleys. Typically pricing ranges
from $160 - $200.
EN-49228 Laser Alignment Tool - Drive Belt
The GM Tool program has now made available a competitive, simple to use and time-saving laser
tool to assist in achieving precise alignment of the drive belt pulleys. This optional tool removes the
guesswork from proper pulley alignment and may serve to reduce comebacks from:
- Drive Belt Noise
- Accelerated Drive Belt Wear
- Drive Belt Slippage
Instructions
The instructions below are specific only to the truck Gen IV V-8 family of engines. These
instructions are only for illustrative purposes to show how the tool may be used. Universal
instructions are included in the box with the Laser Alignment Tool - Drive Belt.
Caution
- Do not look directly into the beam projected from the laser.
- Use caution when shining the laser on highly polished or reflective surfaces. Laser safety glasses
help reduce laser beam glare in many circumstances.
- Always use laser safety glasses when using the laser. Laser safety glasses are not designed to
protect eyes from direct laser exposure.
1. Observe and mark the serpentine belt orientation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page 3534
2. Remove the serpentine belt from the accessory drive system.
3. Install the tool onto the power steering pulley. Position the legs of the tool into the outer grooves
of the pulley, farthest from the front of the
engine.
4. Install the retaining cord around the pulley and to the legs of the tool.
5. Put on the laser safety glasses provided with the tool. 6. Depress the switch on the rear of the
tool to activate the light beam. 7. Rotate the power steering pulley as required to project the light
beam onto the crankshaft balancer pulley grooves. 8. Inspect for proper power steering pulley
alignment.
- If the laser beam projects onto the second rib or raised area (1), the pulleys are aligned properly.
- If the laser beam projects more than one-quarter rib 0.9 mm (0.035 in) mis-alignment, adjust the
position of the power steering pulley as required.
- Refer to SI for Power Steering Pulley Removal and Installation procedures.
9. Install the serpentine belt to the accessory drive system in the original orientation.
10. Operate the vehicle and verify that the belt noise concern is no longer present.
Tool Information
Please visit the GM service tool website for pricing information or to place your order for this tool.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page 3535
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Drive Belt: >
04-06-01-013 > Apr > 04 > Engine - Serpentine Drive Belt Wear Information
Drive Belt: All Technical Service Bulletins Engine - Serpentine Drive Belt Wear Information
Bulletin No.: 04-06-01-013
Date: April 29, 2004
INFORMATION
Subject: Information on Serpentine Belt Wear
Models: 2004 and Prior Passenger Cars and Trucks 2003-2004 and Prior HUMMER H2
All current GM vehicles designed and manufactured in North America were assembled with
serpentine belts that are made with an EPDM material and should last the life of the vehicle. It is
extremely rare to observe any cracks in EPDM belts and it is not expected that they will require
maintenance before 10 years or 240,000 km (150,000 mi) of use.
Older style belts, which were manufactured with a chloroprene compound, may exhibit cracks
depending on age. However, the onset of cracking typically signals that the belt is only about
halfway through its usable life.
A good rule of thumb for chloroprene-based belts is that if cracks are observed 3 mm (1/8 in) apart,
ALL AROUND THE BELT, the belt may be reaching the end of its serviceable life and should be
considered a candidate for changing. Small cracks spaced at greater intervals should not be
considered as indicative that the belt needs changing.
Any belt that exhibits chunking should be replaced.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Drive Belt: >
01-02-32-007 > Sep > 01 > Accessory Drive Belt - Whining Type Noise
Drive Belt: All Technical Service Bulletins Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Other Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics
Drive Belt: All Technical Service Bulletins Engine - Drive Belt Misalignment Diagnostics
INFORMATION
Bulletin No.: 08-06-01-008A
Date: July 27, 2009
Subject: Diagnosing Accessory Drive Belt / Serpentine Belt Noise and Availability and Use of
Kent-Moore EN-49228 Laser Alignment Tool - Drive Belt
Models:
2010 and Prior GM Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2,
H3 Vehicles 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add a model year and update the Tool Information.
Please discard Corporate Bulletin Number 08-06-01-008 (Section 06 - Engine).
Background
Several aftermarket companies offer laser alignment tools for accessory drive systems that can be
very helpful in eliminating drive belt noise as a result of misaligned pulleys. Typically pricing ranges
from $160 - $200.
EN-49228 Laser Alignment Tool - Drive Belt
The GM Tool program has now made available a competitive, simple to use and time-saving laser
tool to assist in achieving precise alignment of the drive belt pulleys. This optional tool removes the
guesswork from proper pulley alignment and may serve to reduce comebacks from:
- Drive Belt Noise
- Accelerated Drive Belt Wear
- Drive Belt Slippage
Instructions
The instructions below are specific only to the truck Gen IV V-8 family of engines. These
instructions are only for illustrative purposes to show how the tool may be used. Universal
instructions are included in the box with the Laser Alignment Tool - Drive Belt.
Caution
- Do not look directly into the beam projected from the laser.
- Use caution when shining the laser on highly polished or reflective surfaces. Laser safety glasses
help reduce laser beam glare in many circumstances.
- Always use laser safety glasses when using the laser. Laser safety glasses are not designed to
protect eyes from direct laser exposure.
1. Observe and mark the serpentine belt orientation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Other Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page 3549
2. Remove the serpentine belt from the accessory drive system.
3. Install the tool onto the power steering pulley. Position the legs of the tool into the outer grooves
of the pulley, farthest from the front of the
engine.
4. Install the retaining cord around the pulley and to the legs of the tool.
5. Put on the laser safety glasses provided with the tool. 6. Depress the switch on the rear of the
tool to activate the light beam. 7. Rotate the power steering pulley as required to project the light
beam onto the crankshaft balancer pulley grooves. 8. Inspect for proper power steering pulley
alignment.
- If the laser beam projects onto the second rib or raised area (1), the pulleys are aligned properly.
- If the laser beam projects more than one-quarter rib 0.9 mm (0.035 in) mis-alignment, adjust the
position of the power steering pulley as required.
- Refer to SI for Power Steering Pulley Removal and Installation procedures.
9. Install the serpentine belt to the accessory drive system in the original orientation.
10. Operate the vehicle and verify that the belt noise concern is no longer present.
Tool Information
Please visit the GM service tool website for pricing information or to place your order for this tool.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Other Service Bulletins for Drive Belt: >
08-06-01-008A > Jul > 09 > Engine - Drive Belt Misalignment Diagnostics > Page 3550
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Technical Service Bulletins > All Other Service Bulletins for Drive Belt: >
04-06-01-013 > Apr > 04 > Engine - Serpentine Drive Belt Wear Information
Drive Belt: All Technical Service Bulletins Engine - Serpentine Drive Belt Wear Information
Bulletin No.: 04-06-01-013
Date: April 29, 2004
INFORMATION
Subject: Information on Serpentine Belt Wear
Models: 2004 and Prior Passenger Cars and Trucks 2003-2004 and Prior HUMMER H2
All current GM vehicles designed and manufactured in North America were assembled with
serpentine belts that are made with an EPDM material and should last the life of the vehicle. It is
extremely rare to observe any cracks in EPDM belts and it is not expected that they will require
maintenance before 10 years or 240,000 km (150,000 mi) of use.
Older style belts, which were manufactured with a chloroprene compound, may exhibit cracks
depending on age. However, the onset of cracking typically signals that the belt is only about
halfway through its usable life.
A good rule of thumb for chloroprene-based belts is that if cracks are observed 3 mm (1/8 in) apart,
ALL AROUND THE BELT, the belt may be reaching the end of its serviceable life and should be
considered a candidate for changing. Small cracks spaced at greater intervals should not be
considered as indicative that the belt needs changing.
Any belt that exhibits chunking should be replaced.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping
Drive Belt: Testing and Inspection Drive Belt Chirping
Drive Belt Chirping Diagnosis
Drive Belt Chirping Diagnosis
Diagnostic Aids
The chirping noise may be intermittent due to moisture on the drive belt(s) or the accessory drive
pulley(s). In order to duplicate the customers concern, it may be necessary to spray a small amount
of water onto the drive belt(s). If spraying water onto the drive belt(s) duplicates the symptom,
cleaning the accessory drive pulley(s) may be the most probable solution. A loose or improper
installation of a body or suspension component, or other item(s) on the vehicle may also cause the
chirping noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The chirping noise may not be
engine related. This step is to verify that the engine is making the noise. It the engine is not making
the noise do not
proceed any further in this table.
3. The noise may be an internal engine noise. Remove the drive belt(s) and operate the engine for
a few seconds, this will verify if the chirping noise
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3557
is related to the drive belt(s) or not. With the drive belt(s) removed the water pump will not operate
and the engine may overheat. Also diagnostic trouble codes (DTCs) may set when the engine is
operated with the drive belt(s) removed.
4. Inspect the drive belt(s) for signs of pilling. Pilling is the small balls, pills, or strings in the drive
belt grooves caused by the accumulation of
rubber dust.
6. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of an accessory drive component,
or the pulley may be bent inward or outward from a previous repair. Test for a misaligned
accessory drive pulley using a straight edge in the pulley grooves across two or three pulleys. If a
misaligned pulley is found, refer to that accessory drive component for the proper removal and
installation procedure for that pulley.
10. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or
washer was installed. 12. Inspection of the accessory drive pulley(s) should include inspecting for
bends, dents, or other damage to the pulley(s) that would prevent the drive
belt(s) from seating properly in the pulley grooves or on the smooth surface of the pulley when the
back side of the drive belt is used to drive the pulley.
14. Replacing the drive belt(s) when it is not damaged or there is not excessive pilling will only be a
temporary repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3558
Drive Belt: Testing and Inspection Drive Belt Excessive Wear
Drive Belt Excessive Wear Diagnosis
Drive Belt Excessive Wear Diagnosis
Diagnostic Aids
Excessive wear on a drive belt(s) is usually caused by incorrect installation or the incorrect drive
belt(s) for the application. Minor misalignment of the accessory drive pulley(s) will not cause
excessive wear, but will probably cause the drive belt(s) to make a noise or fall off. Excessive
misalignment of the accessory drive pulley(s) will cause excessive wear and may also make the
drive belt(s) fall off.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify that
the drive belt(s) is correctly installed on all of the accessory drive pulleys. Wear on the drive belt(s)
may be caused
by mix-positioning the drive belt(s) by one or more grooves on a pulley(s).
3. The installation of a drive belt(s) that is too wide or too narrow will cause wear on the drive
belt(s). The drive belt(s) ribs should match all of the
grooves on the pulleys.
4. This inspection is to verify that the drive belt(s) is not contacting any part of the engine or body
while the engine is operating. There should be
sufficient clearance when the accessory drive components load varies. The drive belt(s) should not
come in contact with an engine or a body component when snapping the throttle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3559
Drive Belt: Testing and Inspection Drive Belt Falls Off
Drive Belt Falls Off Diagnosis
Drive Belt Falls Off Diagnosis
Diagnostic Aids
If the drive belt(s) repeatedly falls off the accessory drive pulley(s), this may be caused by a pulley
misalignment. An extra load that is quickly applied or released by an accessory drive component
may also cause the drive belt(s) to fall off. Verify that the accessory drive component(s) are
operating properly. If the drive belt(s) is the incorrect length, the drive belt tensioner may not
maintain the proper tension on the drive belt(s).
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify the
condition of the drive belt(s). Damage may have occurred to the drive belt(s) when the drive belt(s)
fell off the
pulley. Inspect the drive belt(s) for cuts, tears, sections of ribs missing, or damaged belt plys.
4. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure of that
pulley.
5. Inspection of the accessory drive pulley(s) should include inspecting for bends, dents, or other
damage that would prevent the drive belt from
seating properly in the pulley grooves or on the smooth surface of a pulley when the back side of
the drive belt(s) is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belt(s) to
fall off. 7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer,
or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive bracket(s) moving under load.
Over tightening the fasteners may cause misalignment of the accessory component bracket(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3560
Drive Belt: Testing and Inspection Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a component or another part of the vehicle to make
rumbling noise. The drive belt(s) may have a condition that can not be seen or felt. Sometimes
replacing the drive belt(s) may be the only repair for the symptom. If after replacing the drive belt(s)
and completing the diagnostic table, the rumbling is only heard with the drive belt(s) installed, there
might be an accessory drive component failure. Varying the load on the accessory drive
component(s) may aid in identifying which component is causing the rumbling noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
symptom is present during diagnosing. Other vehicle components may cause a similar symptom. 3.
This test is to verify that the drive belt(s) is causing the rumbling. Rumbling may be confused with
an internal engine noise due to the similarity in
the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. Operate
the engine for a few seconds, this will verify if the rumbling noise is related to the drive belt(s) or
not. With the drive belt(s) removed the water pump will not operate and the engine may overheat.
Also diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. Inspect the drive belt(s) to ensure that the drive belt(s) is not the cause of the noise. Small
cracks across the fibs of the drive belt(s) will not cause
the noise. Belt separation is identified by the plys of the belt separating, this may be seen at the
edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and acceptable. When the pilling is severe the
drive belt(s) does not have a smooth surface for
proper operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3561
Drive Belt: Testing and Inspection
Drive Belt Chirping
Drive Belt Chirping Diagnosis
Drive Belt Chirping Diagnosis
Diagnostic Aids
The chirping noise may be intermittent due to moisture on the drive belt(s) or the accessory drive
pulley(s). In order to duplicate the customers concern, it may be necessary to spray a small amount
of water onto the drive belt(s). If spraying water onto the drive belt(s) duplicates the symptom,
cleaning the accessory drive pulley(s) may be the most probable solution. A loose or improper
installation of a body or suspension component, or other item(s) on the vehicle may also cause the
chirping noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The chirping noise may not be
engine related. This step is to verify that the engine is making the noise. It the engine is not making
the noise do not
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3562
proceed any further in this table.
3. The noise may be an internal engine noise. Remove the drive belt(s) and operate the engine for
a few seconds, this will verify if the chirping noise
is related to the drive belt(s) or not. With the drive belt(s) removed the water pump will not operate
and the engine may overheat. Also diagnostic trouble codes (DTCs) may set when the engine is
operated with the drive belt(s) removed.
4. Inspect the drive belt(s) for signs of pilling. Pilling is the small balls, pills, or strings in the drive
belt grooves caused by the accumulation of
rubber dust.
6. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of an accessory drive component,
or the pulley may be bent inward or outward from a previous repair. Test for a misaligned
accessory drive pulley using a straight edge in the pulley grooves across two or three pulleys. If a
misaligned pulley is found, refer to that accessory drive component for the proper removal and
installation procedure for that pulley.
10. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer, or
washer was installed. 12. Inspection of the accessory drive pulley(s) should include inspecting for
bends, dents, or other damage to the pulley(s) that would prevent the drive
belt(s) from seating properly in the pulley grooves or on the smooth surface of the pulley when the
back side of the drive belt is used to drive the pulley.
14. Replacing the drive belt(s) when it is not damaged or there is not excessive pilling will only be a
temporary repair.
Drive Belt Excessive Wear
Drive Belt Excessive Wear Diagnosis
Drive Belt Excessive Wear Diagnosis
Diagnostic Aids
Excessive wear on a drive belt(s) is usually caused by incorrect installation or the incorrect drive
belt(s) for the application. Minor misalignment of the accessory drive pulley(s) will not cause
excessive wear, but will probably cause the drive belt(s) to make a noise or fall off. Excessive
misalignment of the accessory drive pulley(s) will cause excessive wear and may also make the
drive belt(s) fall off.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify that
the drive belt(s) is correctly installed on all of the accessory drive pulleys. Wear on the drive belt(s)
may be caused
by mix-positioning the drive belt(s) by one or more grooves on a pulley(s).
3. The installation of a drive belt(s) that is too wide or too narrow will cause wear on the drive
belt(s). The drive belt(s) ribs should match all of the
grooves on the pulleys.
4. This inspection is to verify that the drive belt(s) is not contacting any part of the engine or body
while the engine is operating. There should be
sufficient clearance when the accessory drive components load varies. The drive belt(s) should not
come in contact with an engine or a body component when snapping the throttle.
Drive Belt Falls Off
Drive Belt Falls Off Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3563
Drive Belt Falls Off Diagnosis
Diagnostic Aids
If the drive belt(s) repeatedly falls off the accessory drive pulley(s), this may be caused by a pulley
misalignment. An extra load that is quickly applied or released by an accessory drive component
may also cause the drive belt(s) to fall off. Verify that the accessory drive component(s) are
operating properly. If the drive belt(s) is the incorrect length, the drive belt tensioner may not
maintain the proper tension on the drive belt(s).
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This inspection is to verify the
condition of the drive belt(s). Damage may have occurred to the drive belt(s) when the drive belt(s)
fell off the
pulley. Inspect the drive belt(s) for cuts, tears, sections of ribs missing, or damaged belt plys.
4. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure of that
pulley.
5. Inspection of the accessory drive pulley(s) should include inspecting for bends, dents, or other
damage that would prevent the drive belt from
seating properly in the pulley grooves or on the smooth surface of a pulley when the back side of
the drive belt(s) is used to drive the pulley.
6. Accessory drive component brackets that are bent or cracked will also cause the drive belt(s) to
fall off. 7. Inspection of the fasteners can eliminate the possibility that a incorrect bolt, nut, spacer,
or washer was installed. Missing, loose, or incorrect
fasteners may cause pulley misalignment from the accessory drive bracket(s) moving under load.
Over tightening the fasteners may cause misalignment of the accessory component bracket(s).
Drive Belt Rumbling
Drive Belt Rumbling Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3564
Drive Belt Rumbling Diagnosis
Diagnostic Aids
Vibration from the engine operating may cause a component or another part of the vehicle to make
rumbling noise. The drive belt(s) may have a condition that can not be seen or felt. Sometimes
replacing the drive belt(s) may be the only repair for the symptom. If after replacing the drive belt(s)
and completing the diagnostic table, the rumbling is only heard with the drive belt(s) installed, there
might be an accessory drive component failure. Varying the load on the accessory drive
component(s) may aid in identifying which component is causing the rumbling noise.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
symptom is present during diagnosing. Other vehicle components may cause a similar symptom. 3.
This test is to verify that the drive belt(s) is causing the rumbling. Rumbling may be confused with
an internal engine noise due to the similarity in
the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. Operate
the engine for a few seconds, this will verify if the rumbling noise is related to the drive belt(s) or
not. With the drive belt(s) removed the water pump will not operate and the engine may overheat.
Also diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. Inspect the drive belt(s) to ensure that the drive belt(s) is not the cause of the noise. Small
cracks across the fibs of the drive belt(s) will not cause
the noise. Belt separation is identified by the plys of the belt separating, this may be seen at the
edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and acceptable. When the pilling is severe the
drive belt(s) does not have a smooth surface for
proper operation.
Drive Belt Squeal
Drive Belt Squeal Diagnosis
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3565
Drive Belt Squeal Diagnosis
Diagnostic Aids
A loose or improper installation of a body, or suspension component, or other item(s) on the vehicle
may cause the squeal noise. If the squeal is intermittent, verify that it is not the accessory drive
component(s) by varying their load(s), making sure they are operating to their maximum capacity.
An overcharged air conditioning (A/C) system, a power steering system restriction or the incorrect
fluid, or a failing generator are suggested items to inspect.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. The squeal may not be engine
related. This step is to verify that the engine is making the noise. If the engine is not making the
noise do not
proceed further in this table.
3. The squeal may be an internal engine noise. Remove the drive belt(s) and operate the engine
for a few seconds, this will verify if the squealing
noise is related to the drive belt(s) or an accessory drive component. With the drive belt(s) removed
the water pump will not operate and the engine may overheat. Also diagnostic trouble codes
(DTCs) may set when the engine is operated with the drive belt(s) removed.
4. This test is to verify that an accessory drive component(s) does not have a seized bearing. With
the belt(s) removed, test the bearings in the
accessory drive component(s) for smooth operation. Also test the accessory drive component(s)
with the engine operating by varying the load on the accessory drive component(s) to verify that the
component(s) is operating properly.
5. This test is to verify that the drive belt(s) tensioner(s) are not operating properly. If the drive belt
tensioner(s) are not operating properly, proper
belt tension may not be achieved to keep the drive belt(s) from slipping which could cause a
squealing noise.
6. This test is to verify that the drive belt(s) is not too long, which would prevent the drive belt
tensioner(s) from operating properly. Also if the
incorrect length drive belt(s) was installed, it may not be routed correctly and may be turning an
accessory drive component in the incorrect direction.
7. Misalignment of the accessory drive pulley(s) may be caused from improper mounting or
incorrect installation of a accessory drive component, or
the pulley may be bent inward or outward from a previous repair. Test for a misaligned pulley using
a straight edge in the pulley grooves across two or three pulleys. If a misaligned pulley is found,
refer to that accessory drive component for the proper removal and installation procedure for that
pulley.
8. Inspect the accessory drive pulley(s) to verify that they are the correct diameter or width. Using a
known good vehicle, compare the accessory
drive pulleys.
Drive Belt Vibration
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3566
Drive Belt Vibration Diagnosis
Drive Belt Vibration Diagnosis
Diagnostic Aids
The accessory drive components may have an affect on engine vibration. An overcharged air
conditioning (A/C) system, a power steering system restriction, or the incorrect fluid, or an extra
load placed on the generator are suggested items to inspect. To help identify an intermittent or an
improper condition, vary the loads on the accessory drive components.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 2. This test is to verify that the
vibration is present during diagnosing. Other vehicle components may cause a similar symptom
such as the exhaust
system, or the drivetrain.
3. This test is to verify that the drive belt(s) or accessory drive components may be causing the
vibration. Remove the drive belt(s) and operate the
engine for a few seconds, this will verify if the vibration is related to the drive belt(s) or not. With the
drive belt(s) removed the water pump will not operate and the engine may overheat. Also
diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. The drive belt(s) may cause a vibration. While the drive belt(s) is removed this is the best time to
inspect the condition of the drive belt(s). 6. Inspection of the fasteners can eliminate the possibility
that a incorrect bolt, nut, spacer, or washer was installed. 8. This step should only be performed if
the fan is driven by the drive belt. Inspect the engine cooling fan for bent, twisted, loose, or cracked
blades.
Inspect the fan clutch for smooth operation. Inspect for a bent fan shaft or bent mounting flange.
9. Inspect the water pump drive shaft for being bent. Also inspect the water pump bearings for
smooth operation and excessive play. Compare the
water pump with a known, good water pump.
10. Accessory drive component brackets that are bent, cracked, or loose may put an extra strain on
that accessory drive component causing it to
vibrate.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Testing and Inspection > Drive Belt Chirping > Page 3567
Drive Belt Whine
Drive Belt Whine Diagnosis
Drive Belt Whine Diagnosis
Diagnostic Aids
The drive belt(s) will not cause the whine. If the whine is intermittent, verify that it is not the
accessory drive component(s) by varying their loads, making sure they are operating to their
maximum capacity. An overcharged air conditioning (A/C) system, a power steering system
restriction or the incorrect fluid, or a failing generator are suggested items to inspect.
Test Description
The number(s) below refer to the step(s) in the diagnostic table. 3. This test is to verify that the
whine is being caused by the accessory drive component(s). Remove the drive belt(s) and operate
the engine for a
few seconds this will verify if the whining noise is related to the accessory drive component. With
the drive belt(s) removed the water pump will not operate and the engine may overheat. Also
diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt(s)
removed.
4. This inspection should include checking the drive belt tensioner and the drive belt idler pulley
bearings. The drive belt(s) may have to be installed
and the accessory drive components operated separately by varying their loads. Refer to the
suspected accessory drive component for the proper removal and installation procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Service and Repair > Accessory Drive Belt Replacement
Drive Belt: Service and Repair Accessory Drive Belt Replacement
Drive Belt Replacement - Accessory
Removal Procedure
1. Loosen the air cleaner outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
2. Remove the radiator inlet hose clip from the outlet duct. 3. Remove the air cleaner outlet duct.
4. Install a breaker bar with hex-head socket to the drive belt tensioner bolt. 5. Rotate the drive belt
tensioner clockwise in order to relieve tension on the belt. 6. Remove the belt from the pulleys and
the drive belt tensioner. 7. Slowly release the tension on the drive belt tensioner. 8. Remove the
breaker bar and socket and from the drive belt tensioner bolt. 9. Clean and inspect the belt
surfaces of all the pulleys.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Service and Repair > Accessory Drive Belt Replacement > Page 3570
1. Route the drive belt around all the pulleys except the idler pulley. 2. Install the breaker bar with
hex-head socket to the belt tensioner bolt. 3. Rotate the belt tensioner clockwise in order to relieve
the tension on the tensioner. 4. Install the drive belt under the idler pulley. 5. Slowly release the
tension on the belt tensioner. 6. Remove the breaker bar and socket from the belt tensioner bolt. 7.
Inspect the drive belt for proper installation and alignment.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
8. Install the air cleaner outlet duct. 9. Install the radiator inlet hose clip to the outlet duct.
Notice: Refer to Fastener Notice in Service Precautions.
10. Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Service and Repair > Accessory Drive Belt Replacement > Page 3571
Drive Belt: Service and Repair A/C Belt
Drive Belt Replacement - Air Conditioning
Removal Procedure
1. Remove the accessory drive belt. 2. Raise and suitably support the vehicle. Refer to Vehicle
Lifting. 3. Remove the engine shield bolts. 4. Remove the engine shield.
5. Install a ratchet into the air conditioning (A/C) belt tensioner adapter opening. 6. Rotate the A/C
belt tensioner clockwise in order to relieve tension on the belt. 7. Remove the A/C belt from the
pulleys. 8. Slowly release the tension on the A/C belt tensioner. 9. Remove the ratchet from the
A/C belt tensioner.
10. Clean and inspect the belt surfaces of all the pulleys.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt > Component Information > Service and Repair > Accessory Drive Belt Replacement > Page 3572
1. Install the A/C belt around the crankshaft balancer. 2. Install a ratchet into the A/C drive belt
tensioner adapter opening 3. Rotate the A/C belt tensioner clockwise in order to relieve tension on
the tensioner. 4. Install the A/C belt over the idler pulley. 5. Install the A/C belt around the A/C
compressor pulley. 6. Slowly release the tension on the A/C belt tensioner. 7. Remove the ratchet
from the A/C belt tensioner. 8. Inspect the A/C belt for proper installation and alignment.
9. Install the engine shield.
Notice: Refer to Fastener Notice in Service Precautions.
10. Install the engine shield bolts.
- Tighten the engine shield bolts to 20 Nm (15 ft. lbs.).
11. Lower the vehicle. 12. Install the accessory drive belt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt Tensioner > Component Information > Specifications
Drive Belt Tensioner: Specifications
Accessory Drive Belt Tensioner Bolt
.................................................................................................................................................... 50
Nm (37 ft. lbs.) Air Conditioning (A/C) Belt Tensioner Bolt
............................................................................................................................................ 50 Nm (37
ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt Tensioner > Component Information > Specifications > Page 3576
Drive Belt Tensioner: Testing and Inspection
Drive Belt Tensioner Diagnosis
Inspection Procedure
Notice: Allowing the drive belt tensioner to snap into the free position may result in damage to the
tensioner.
Important: When the engine is operating the drive belt tensioner arm will move. Do not replace the
drive belt tensioner because of movement in the drive belt tensioner arm.
1. Remove the drive belt. 2. Move the drive belt tensioner through its full travel.
- The movement should feel smooth.
- There should be no binding.
- The tensioner should return freely.
3. If any binding is observed, replace the drive belt tensioner. 4. Install the drive belt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt Tensioner > Component Information > Service and Repair > Drive Belt Tensioner Replacement (Accessory)
Drive Belt Tensioner: Service and Repair Drive Belt Tensioner Replacement (Accessory)
Drive Belt Tensioner Replacement - Accessory
Removal Procedure
1. Remove the accessory drive belt. 2. Remove the drive belt tensioner bolts. 3. Remove the drive
belt tensioner.
Installation Procedure
1. Install the drive belt tensioner. 2. Install the drive belt tensioner bolts.
Notice: Refer to Fastener Notice in Service Precautions.
3. Tighten the drive belt tensioner bolts.
- Tighten the accessory drive belt tensioner bolts to 50 Nm (37 ft. lbs.).
4. Install the accessory drive belt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Drive Belt Tensioner > Component Information > Service and Repair > Drive Belt Tensioner Replacement (Accessory) >
Page 3579
Drive Belt Tensioner: Service and Repair Drive Belt Tensioner Replacement (Air Conditioning)
Drive Belt Tensioner Replacement - Air Conditioning
Removal Procedure
1. Remove the air conditioning (A/C) drive belt. 2. Remove the A/C belt tensioner bolts. 3. Remove
the A/C belt tensioner.
Installation Procedure
1. Install the A/C belt tensioner.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the A/C belt tensioner bolts.
- Tighten the A/C belt tensioner bolts to 50 Nm (37 ft. lbs.).
3. Install the A/C drive belt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Accessory Bracket > Component Information > Specifications
Engine Accessory Bracket: Specifications
Engine Service Lift Bracket
M10 Bolt ..............................................................................................................................................
................................................ 50 Nm (37 ft. lbs.) M8 Bolt ..................................................................
........................................................................................................................... 25 Nm (18 ft. lbs.)
Engine Shield Bolt ...............................................................................................................................
................................................. 20 Nm (15 ft. lbs.) Engine Wiring Harness Bracket Nut
................................................................................................................................................... 5 Nm
(44 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Accessory Bracket > Component Information > Service and Repair > Engine Mount Bracket Replacement - Left
Engine Accessory Bracket: Service and Repair Engine Mount Bracket Replacement - Left
Engine Mount Bracket Replacement- Left
Removal Procedure
1. Remove the engine mount. 2. Remove the engine mount bracket bolts. 3. Remove the engine
mount bracket.
Installation Procedure
1. Install the engine mount bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the engine mount bracket bolts.
- Tighten the engine mount bracket bolts to 75 Nm (55 ft. lbs.).
3. Install the engine mount.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Accessory Bracket > Component Information > Service and Repair > Engine Mount Bracket Replacement - Left >
Page 3585
Engine Accessory Bracket: Service and Repair Engine Mount Bracket Replacement- Right
Engine Mount Bracket Replacement- Right
Removal Procedure
1. Remove the engine mount. 2. Remove the engine mount bracket bolts. 3. Remove the engine
mount bracket.
Installation Procedure
1. Install the engine mount bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the engine mount bracket bolts.
- Tighten the engine mount bracket bolts to 75 Nm (55 ft. lbs.).
3. Install the engine mount.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Specifications
Engine Mount: Specifications
Engine Mount Bolt ...............................................................................................................................
.................................................... 50 Nm (37 ft. lbs.) Engine Mount Bracket Bolt ...............................
....................................................................................................................................... 75 Nm (55 ft.
lbs.) Engine Mount-to-Engine Mount Bracket Bolt
.......................................................................................................................................... 50 Nm (37
ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection
Engine Mount: Service and Repair Engine Mount Inspection
Engine Mount Inspection
Notice: Broken or deteriorated mounts can cause misalignment and destruction of certain drive
train components. When a single mount breaks, the remaining mounts are subjected to abnormally
high stresses.
Notice: When raising or supporting the engine for any reason, do not use a jack under the oil pan,
any sheet metal, or the crankshaft pulley. Due to the small clearance between the oil pan and the
oil pump screen, jacking against the oil pan may cause the pan to be bent against the pump
screen. This will result in a damaged oil pickup unit.
1. Measure the engine movement at the engine mount in order to check for damage to the rubber
portions of the mount.
1.1. Apply the park brake.
1.2. Start the engine.
1.3. Firmly apply and hold the primary brakes.
1.4. Have an assistant stand to the side of the vehicle in order to observe for engine movement.
1.5. Slightly load the engine shifting from drive to reverse a few times.
1.6. If the engine moves more than 24 mm (0.945 inch)from the at rest position, in either direction,
check for loose engine mount bolts.
2. If the engine mount bolt torque is within specifications, check the condition of the engine mount.
3. Replace the engine mount if any of the following conditions exist:
- Heat check cracks cover the rubber cushion surface.
- The rubber cushion is separated from the metal plate of the mount.
- There is a split through the rubber cushion.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3591
Engine Mount: Service and Repair Engine Mount Replacement - Left
Engine Mount Replacement- Left
Removal Procedure
Notice: When raising or supporting the engine for any reason, do not use a jack under the oil pan,
any sheet metal, or the crankshaft pulley. Due to the small clearance between the oil pan and the
oil pump screen, jacking against the oil pan may cause the pan to be bent against the pump
screen. This will result in a damaged oil pickup unit.
1. Remove the engine mount-to-engine mount bracket bolts. (Right side shown, left side similar).
2. If vehicle is a 2 wheel drive (2WD), raise the vehicle to a height to work through the front
wheelhouse opening. 3. If vehicle is a 4 wheel drive (4WD), raise the vehicle in order to remove the
front tires and wheels. 4. Remove the left front tire and wheel. 5. Remove the wheelhouse inner
panel push pin retainers (2). 6. Remove the wheelhouse inner panel (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3592
7. Remove the engine shield bolts. 8. Remove the engine shield.
Important: DO NOT raise and/or support the engine by the crankshaft balancer, or oil pan.
9. Raise and suitably support the engine using adjustable (screw type) jack stands.
10. Remove the engine mount bolts. 11. For vehicles with 4WD, remove the front propeller shaft.
12. Remove the left engine mount.
Installation Procedure
1. Position the left engine mount to the engine.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3593
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the engine mount bolts.
- Tighten the engine mount bolts to 50 Nm (37 ft. lbs.).
3. Lower the engine. 4. Remove the adjustable jack stands. 5. Install the front propeller shaft.
6. Position the engine shield to the vehicle. 7. Install the engine shield bolts.
- Tighten the engine shield bolts to 20 Nm (15 ft. lbs.).
8. Lower the vehicle.
9. Install the left front tire and wheel.
10. Install the wheelhouse inner panel push pin retainers (2). 11. Install the wheelhouse inner panel
(1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3594
12. Install the engine mount-to-engine mount bracket bolts. (Right side shown, left side similar).
- Tighten the engine mount-to-engine mount bracket bolts to 65 Nm (48 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3595
Engine Mount: Service and Repair Engine Mount Replacement - Right
Engine Mount Replacement - Right
Removal Procedure
1. Remove the engine mount-to-engine mount bracket bolts. 2. Raise and suitably support the
vehicle. Refer to Vehicle Lifting.
3. Remove the engine shield bolts. 4. Remove the engine shield. 5. Remove the air conditioning
(A/C) compressor. 6. Remove the starter motor.
Important: DO NOT raise and/or support the engine by the crankshaft balancer, or oil pan.
7. Raise and suitably support the engine using adjustable (screw type) jack stands.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3596
8. Remove the engine mount bolts. 9. Remove the right engine mount.
Installation Procedure
1. Position the right engine mount to the engine.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the engine mount bolts.
- Tighten the engine mount bolts to 50 Nm (37 ft. lbs.).
3. Lower the engine. 4. Remove the adjustable jack stands. 5. Install the starter motor. 6. Install the
A/C compressor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Engine Mount > Component Information > Service and Repair > Engine Mount Inspection > Page 3597
7. Position the engine shield to the vehicle. 8. Install the engine shield bolts.
- Tighten the engine shield bolts to 20 Nm (15 ft. lbs.).
9. Lower the vehicle.
10. Install the engine mount-to-engine mount bracket bolts.
- Tighten the engine mount-to-engine mount bracket bolts to 65 Nm (48 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Idler Pulley > Component Information > Specifications
Idler Pulley: Specifications
Drive Belt Idler Pulley Bolt ...................................................................................................................
................................................... 50 Nm (37 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Drive Belts, Mounts, Brackets and Accessories >
Idler Pulley > Component Information > Specifications > Page 3601
Idler Pulley: Service and Repair
Drive Belt Idler Pulley Replacement
Removal Procedure
1. Loosen the drive belt idler pulley bolt. 2. Remove the accessory drive belt. 3. Remove the drive
belt idler pulley and bolt.
Installation Procedure
1. Install the drive belt idler pulley and bolt to the generator bracket. Snug the bolt finger tight. 2.
Install the drive belt.
Notice: Refer to Fastener Notice in Service Precautions.
3. Tighten the drive belt idler pulley bolt.
- Tighten the drive belt idler pulley bolt to 50 Nm (37 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil Pressure >
Component Information > Specifications
Engine Oil Pressure: Specifications
Oil Pressure Minimum - Hot
At 1,000 Revolutions Per Minute (RPM)
...................................................................................................................................................... 41
kPa (6 psig) At 2,000 RPM ..................................................................................................................
.......................................................................... 124 kPa (18 psig) At 4,000 RPM ..............................
..............................................................................................................................................................
165 kPa (24 psig)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil Pressure >
Component Information > Specifications > Page 3606
Engine Oil Pressure: Testing and Inspection
Oil Pressure Diagnosis and Testing
- Tools Required J 21867 Pressure Gauge
- J 42907 Oil Pressure Testing Tool
1. With the vehicle on a level surface, run the vehicle for a few minutes, allow adequate drain down
time, 2-3 minutes, and measure the oil level. 2. If required, add the recommended grade engine oil
and fill the crankcase until the oil level measures full on the oil level indicator. 3. Run the engine
briefly, 10-15 seconds, and verify low or no oil pressure on the vehicle gauge or light. 4. Listen for a
noisy valve train or a knocking noise. 5. Inspect for the following:
- Oil diluted by water or glycol anti freeze
- Foamy oil
6. Remove the oil filter and install the J 42907. 7. install J21867 or equivalent to the J42907. 8. Run
the engine and measure the engine oil pressure. 9. Compare the readings to Engine Mechanical
Specifications.
10. If the engine oil pressure is below specifications, inspect the engine for one or more of the
following:
- Oil pump worn or dirty.
- Oil pump-to-engine block bolts loose.
- Oil pump screen loose, plugged, or damaged
- Oil pump screen O-ring seal missing or damaged
- Malfunctioning oil pump pressure regulator valve
- Excessive bearing clearance
- Cracked, porous, or restricted oil galleries
- Oil gallery plugs missing or incorrectly installed.
- Broken valve lifters Repair as necessary
11. If the oil pressure reading on the J 21867 or equivalent is within specifications, inspect for the
following:
- Plugged or incorrect oil filter and/or malfunctioning oil bypass valve
- Malfunctioning oil pressure gauge or sensor Repair as necessary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil Dip Stick - Dip
Stick Tube > Component Information > Specifications
Engine Oil Dip Stick - Dip Stick Tube: Specifications
Oil Level Indicator Tube Bolt ...............................................................................................................
................................................... 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil Dip Stick - Dip
Stick Tube > Component Information > Specifications > Page 3610
Engine Oil Dip Stick - Dip Stick Tube: Service and Repair
Oil Level Indicator and Tube Replacement
Removal Procedure
1. Remove the oil level indicator from the tube.
2. Remove the oil level indicator tube bolt. 3. Remove the oil level indicator tube from the engine
block.
Important: The O-ring seal may be reused if not cut or damaged.
4. Inspect the O-ring seal for cuts or damage. 5. Remove the O-ring seal from the tube (if required).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil Dip Stick - Dip
Stick Tube > Component Information > Specifications > Page 3611
1. Lubricate the O-ring seal with clean engine oil. 2. Install the O-ring seal onto the oil level
indicator tube. 3. Install the oil level indicator tube behind the exhaust manifold. 4. Raise and
suitably support the vehicle. Refer to Vehicle Lifting. 5. Install the oil level indicator tube into the
block. The tube must be installed with the collar flush to the block. 6. Lower the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
7. Install the oil level indicator tube bolt
- Tighten the oil level indicator tube bolt to 25 Nm (18 ft. lbs.).
8. Install the oil level indicator to the tube.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Technical Service Bulletins > Engine - GM dexos 1 and dexos 2(R) Oil Specifications
Engine Oil: Technical Service Bulletins Engine - GM dexos 1 and dexos 2(R) Oil Specifications
INFORMATION
Bulletin No.: 11-00-90-001
Date: March 14, 2011
Subject: Global Information for GM dexos1(TM) and GM dexos2(TM) Engine Oil Specifications for
Spark Ignited and Diesel Engines, Available Licensed Brands, and Service Fill for Adding or
Complete Oil Change
Models:
2012 and Prior GM Passenger Cars and Trucks Excluding All Vehicles Equipped with
Duramax(TM) Diesel Engines
GM dexos 1(TM) Information Center Website
Refer to the following General Motors website for dexos 1(TM) information about the different
licensed brands that are currently available: http://www.gmdexos.com
GM dexos 1(TM) Engine Oil Trademark and Icons
The dexos(TM) specification and trademarks are exclusive to General Motors, LLC.
Only those oils displaying the dexos‹›(TM) trademark and icon on the front label meet the
demanding performance requirements and stringent quality standards set forth in the dexos‹›(TM)
specification.
Look on the front label for any of the logos shown above to identify an authorized, licensed dexos
1(TM) engine oil.
GM dexos 1(TM) Engine Oil Specification
Important General Motors dexos 1(TM) engine oil specification replaces the previous General
Motors specifications GM6094M, GM4718M and GM-LL-A-025 for most GM gasoline engines. The
oil specified for use in GM passenger cars and trucks, PRIOR to the 2011 model year remains
acceptable for those previous vehicles. However, dexos 1(TM) is backward compatible and can be
used in those older vehicles.
In North America, starting with the 2011 model year, GM introduced dexos 1(TM) certified engine
oil as a factory fill and service fill for gasoline engines. The reasons for the new engine oil
specification are as follows:
- To meet environmental goals such as increasing fuel efficiency and reducing engine emissions.
- To promote long engine life.
- To minimize the number of engine oil changes in order to help meet the goal of lessening the
industry's overall dependence on crude oil.
dexos 1(TM) is a GM-developed engine oil specification that has been designed to provide the
following benefits:
- Further improve fuel economy, to meet future corporate average fuel economy (CAFE)
requirements and fuel economy retention by allowing the oil to maintain its fuel economy benefits
throughout the life of the oil.
- More robust formulations for added engine protection and aeration performance.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Technical Service Bulletins > Engine - GM dexos 1 and dexos 2(R) Oil Specifications > Page 3616
- Support the GM Oil Life System, thereby minimizing the replacement of engine oil, before its life
has been depleted.
- Reduce the duplication of requirements for a large number of internal GM engine oil
specifications.
International Lubricants Standardization and Approval Committee (ILSAC)
GF-5 Standard
In addition to GM dexos 1(TM), a new International Lubricants Standardization and Approval
Committee (ILSAC) standard called GF-5, was introduced in October 2010.
- There will be a corresponding API category, called: SN Resource Conserving. The current GF-4
standard was put in place in 2004 and will become obsolete in October 2011. Similar to dexos
1(TM), the GF-5 standard will use a new fuel economy test, Sequence VID, which demands a
statistically significant increase in fuel economy versus the Sequence VIB test that was used for
GF-4.
- It is expected that all dexos 1(TM) approved oils will be capable of meeting the GF-5 standard.
However, not all GF-5 engine oils will be capable of meeting the dexos 1(TM) specification.
- Like dexos(TM), the new ILSAC GF-5 standard will call for more sophisticated additives. The API
will begin licensing marketers during October 2010, to produce and distribute GF-5 certified
products, which are expected to include SAE 0W-20, 0W-30, 5W-20, 5W-30 and 10W-30 oils.
Corporate Average Fuel Economy (CAFE) Requirements Effect on Fuel Economy
Since CAFE standards were first introduced in 1974, the fuel economy of cars has more than
doubled, while the fuel economy of light trucks has increased by more than 50 percent. Proposed
CAFE standards call for a continuation of increased fuel economy in new cars and trucks. To meet
these future requirements, all aspects of vehicle operation are being looked at more critically than
ever before.
New technology being introduced in GM vehicles designed to increase vehicle efficiency and fuel
economy include direct injection, cam phasing, turbocharging and active fuel management (AFM).
The demands of these new technologies on engine oil also are taken into consideration when
determining new oil specifications. AFM for example can help to achieve improved fuel economy.
However alternately deactivating and activating the cylinders by not allowing the intake and
exhaust valves to open contributes to additional stress on the engine oil.
Another industry trend for meeting tough fuel economy mandates has been a shift toward lower
viscosity oils.
dexos 1(TM) will eventually be offered in several viscosity grades in accordance with engine needs:
SAE 0W-20, 5W-20, 0W-30 and 5W-30.
Using the right viscosity grade oil is critical for proper engine performance. Always refer to the
Maintenance section of a vehicle Owner Manual for the proper viscosity grade for the engine being
serviced.
GM Oil Life System in Conjunction With dexos (TM) Supports Extended Oil Change Intervals
To help conserve oil while maintaining engine protection, many GM vehicles are equipped with the
GM Oil Life System. This system can provide oil change intervals that exceed the traditional 3,000
mile (4,830 km) recommendation.
The dexos (TM) specification, with its requirements for improved oil robustness, compliments the
GM Oil Life System by supporting extended oil change intervals over the lifetime of a vehicle.
If all GM customers with GM Oil Life System equipped vehicles would use the system as intended,
GM estimates that more than 100 million gallons of oil could be saved annually.
GM dexos 2(TM) Information Center Website
Refer to the following General Motors website for dexos 2(TM) information about the different
licensed brands that are currently available: http://www.gmdexos.com
GM dexos 2(TM) Engine Oil Trademark and Icons
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Technical Service Bulletins > Engine - GM dexos 1 and dexos 2(R) Oil Specifications > Page 3617
The dexos (TM) specification and trademarks are exclusive to General Motors, LLC.
Only those oils displaying the dexos (TM) trademark and icon on the front label meet the
demanding performance requirements and stringent quality standards set forth in the dexos
(TM)specification.
Look on the front label for any of the logos shown above to identify an authorized, licensed dexos
2(TM) engine oil.
GM dexos 2(TM) Engine Oil Specification
- dexos 2(TM) is approved and recommended by GM for use in Europe starting in model year 2010
vehicles, regardless of where the vehicle was manufactured.
- dexos 2(TM) is the recommended service fill oil for European gasoline engines.
Important The Duramax(TM) diesel engine is the exception and requires lubricants meeting
specification CJ-4.
- dexos 2(TM) is the recommended service fill oil for European light-duty diesel engines and
replaces GM-LL-B-025 and GM-LL-A-025.
- dexos 2(TM) protects diesel engines from harmful soot deposits and is designed with limits on
certain chemical components to prolong catalyst life and protect expensive emission reduction
systems. It is a robust oil, resisting degradation between oil changes and maintaining optimum
performance longer.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Specifications > Capacity Specifications
Engine Oil: Capacity Specifications
Engine Oil
With Filter Change ...............................................................................................................................
............................................................. 5.7L (6.0 Qt)
NOTE: ALL capacity specifications are approximate. When replacing or adding fluids, fill to the
recommended level and recheck fluid level.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Specifications > Capacity Specifications > Page 3620
Engine Oil: Fluid Type Specifications
Engine Oil
API Classification .................................................................................................................................
........................................ Look for Starburst Symbol Grade ...............................................................
......................................................................................................................................... 5W-30
(preferred) Above -18° C (0° F) ...........................................................................................................
........................................................ 10W-30, 5W-30 (preferred)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Specifications > Page 3621
Engine Oil: Service and Repair
Engine Oil and Oil Filter Replacement
Removal Procedure
Important: In order to completely drain the oil from the oil pan internal baffling, the bottom of the oil
pan must be level during the oil drain procedure.
1. Open the hood. 2. Remove the oil fill cap. 3. Raise and suitably support the vehicle. Refer to
Vehicle Lifting. 4. Place a oil drain pan under the oil pan drain plug. 5. Remove the oil pan drain
plug. 6. Drain the engine oil. 7. Wipe the excess oil from the drain plug hole and plug.
8. Remove the oil filter from the engine block.
Important: Check the old oil filter to ensure that the filter seal is not left on the engine block.
9. Wipe the excess oil from the oil filter mounting.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Engine Oil > Component
Information > Specifications > Page 3622
1. Lubricate the oil filter seal with clean engine oil.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the oil filter to the engine block.
- Tighten the oil filter to 30 Nm (22 ft. lbs.).
3. install the oil drain plug to the engine block.
- Tighten the oil pan drain plug to 25 Nm (18 ft. lbs.).
4. Lower the vehicle. 5. Fill the crankcase with the proper quantity and grade of engine oil. 6.
Remove the oil level indicator. 7. Wipe the indicator with a clean cloth. 8. Install the oil level
indicator. 9. Remove the oil level indicator in order to check the level.
10. Add oil if necessary: 11. Close the hood.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Technical Service Bulletins > Engine - Noise/Damage Oil Filter Application Importance
Oil Filter: Technical Service Bulletins Engine - Noise/Damage Oil Filter Application Importance
INFORMATION
Bulletin No.: 07-06-01-016B
Date: July 27, 2009
Subject: Information on Internal Engine Noise or Damage After Oil Filter Replacement
Models:
2010 and Prior Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2, H3
2009 and Prior Saab 9-7X
Supercede: This bulletin is being updated to add model years. Please discard Corporate Bulletin
Number 07-06-01-016A (Section 06 - Engine/Propulsion System).
Important Engine damage that is the result of an incorrect or improperly installed engine oil filter is
not a warrantable claim. The best way to avoid oil filter quality concerns is to purchase ACDelco(R)
oil filters directly from GMSPO.
Oil filter misapplication may cause abnormal engine noise or internal damage. Always utilize the
most recent parts information to ensure the correct part number filter is installed when replacing oil
filters. Do not rely on physical dimensions alone. Counterfeit copies of name brand parts have been
discovered in some aftermarket parts systems. Always ensure the parts you install are from a
trusted source. Improper oil filter installation may result in catastrophic engine damage.
Refer to the appropriate Service Information (SI) installation instructions when replacing any oil
filter and pay particular attention to procedures for proper cartridge filter element alignment. If the
diagnostics in SI (Engine Mechanical) lead to the oil filter as the cause of the internal engine noise
or damage, dealers should submit a field product report. Refer to Corporate Bulletin Number
02-00-89-002I (Information for Dealers on How to Submit a Field Product Report).
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Specifications > Mechanical Specifications
Oil Filter: Mechanical Specifications
Fastener Tightening Specifications
Oil Filter ...............................................................................................................................................
.................................................... 30 Nm (22 ft. lbs.) Oil Filter Fitting ..................................................
....................................................................................................................................... 55 Nm (40 ft.
lbs.)
Engine Mechanical Specifications (5.3L Engine)
Oil Filter Type ......................................................................................................................................
......................................................................... PF59
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Specifications > Mechanical Specifications > Page 3629
Oil Filter: Capacity Specifications
Oil Capacity
With Filter Change ...............................................................................................................................
......................................... 5.68 Liters (6.0 Quarts) Without Filter Change ..........................................
........................................................................................................................ 4.73 Liters (5.0 Quarts)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Specifications > Mechanical Specifications > Page 3630
Oil Filter: Fluid Type Specifications
Oil Type ...............................................................................................................................................
....................................................................... 5W-30
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Specifications > Page 3631
Oil Filter: Service and Repair
Engine Oil and Oil Filter Replacement
Removal Procedure
Important: In order to completely drain the oil from the oil pan internal baffling, the bottom of the oil
pan must be level during the oil drain procedure.
1. Open the hood. 2. Remove the oil fill cap. 3. Raise and suitably support the vehicle. Refer to
Vehicle Lifting. 4. Place a oil drain pan under the oil pan drain plug. 5. Remove the oil pan drain
plug. 6. Drain the engine oil. 7. Wipe the excess oil from the drain plug hole and plug.
8. Remove the oil filter from the engine block.
Important: Check the old oil filter to ensure that the filter seal is not left on the engine block.
9. Wipe the excess oil from the oil filter mounting.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter, Engine >
Component Information > Specifications > Page 3632
1. Lubricate the oil filter seal with clean engine oil.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the oil filter to the engine block.
- Tighten the oil filter to 30 Nm (22 ft. lbs.).
3. install the oil drain plug to the engine block.
- Tighten the oil pan drain plug to 25 Nm (18 ft. lbs.).
4. Lower the vehicle. 5. Fill the crankcase with the proper quantity and grade of engine oil. 6.
Remove the oil level indicator. 7. Wipe the indicator with a clean cloth. 8. Install the oil level
indicator. 9. Remove the oil level indicator in order to check the level.
10. Add oil if necessary: 11. Close the hood.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter Adapter >
Component Information > Specifications
Oil Filter Adapter: Specifications
Oil Filter Adapter ..................................................................................................................................
................................................... 55 Nm (40 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter Adapter >
Component Information > Service and Repair > Oil Filter Adapter Replacement
Oil Filter Adapter: Service and Repair Oil Filter Adapter Replacement
Oil Filter Adapter Replacement
Removal Procedure
1. Drain the engine oil. 2. Remove the oil filter.
3. Remove the oil filter adapter (1).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter Adapter >
Component Information > Service and Repair > Oil Filter Adapter Replacement > Page 3638
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the oil filter adapter (1).
- Tighten the oil filter adapter to 55 Nm (40 ft. lbs.).
2. Install the oil filter. 3. Refill the engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter Adapter >
Component Information > Service and Repair > Oil Filter Adapter Replacement > Page 3639
Oil Filter Adapter: Service and Repair Oil Filter Bypass Valve Replacement
Oil Filter Bypass Valve Replacement
Removal Procedure
1. Drain the engine oil. 2. Remove the oil filter.
3. Remove the oil filter adapter (1). 4. Remove the oil filter bypass valve (2).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Filter Adapter >
Component Information > Service and Repair > Oil Filter Adapter Replacement > Page 3640
1. Install the oil filter bypass valve (2).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the oil filter adapter (1).
- Tighten the oil filter adapter to 55 Nm (40 ft. lbs.).
3. Install the oil filter.
- Tighten the oil filter to 30 Nm (22 ft. lbs.).
4. Refill the engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Level Sensor >
Component Information > Specifications
Oil Level Sensor: Specifications
Oil Level Sensor ..................................................................................................................................
................................................ 13 Nm (115 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Level Sensor >
Component Information > Specifications > Page 3644
Oil Level Sensor: Service and Repair
Engine Oil Level Sensor and/or Switch Replacement
Removal Procedure
1. Drain the engine oil. 2. Disconnect the oil level sensor electrical connector (6).
3. Remove the oil level sensor from the oil pan.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the oil level sensor to the oil pan.
- Tighten the oil level sensor to 13 Nm (115 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Level Sensor >
Component Information > Specifications > Page 3645
2. Connect the oil level sensor electrical connector (6). 3. Fill the engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Level Sensor For ECM >
Component Information > Diagrams
Engine Oil Level Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair
Oil Line: Service and Repair
Engine Oil Cooler Hose/Pipe Replacement (6.0L and 8.1. Engines)
Removal Procedure
The optional oil cooler is either an integral part of the radiator or a separate unit placed in front of
the radiator. The cooler lines and hoses are serviceable. 1. Disengage the plastic caps from the
quick connect fittings. Pull the caps back along the pipe. 2. Hold one leg of the retaining clip. 3.
Using a small pick-type tool or, bent screwdriver, gently pry the other end of the retaining clip from
the quick connect fitting. 4. Rotate the retaining clip out of the quick connect fitting. Remove the
retaining clip completely. 5. Discard the OLD retaining clip.
6. If equipped with a 6.OL engine, perform the following:
6.1. Open the oil cooler hose clip located on the lower fan shroud.
6.2. Remove the oil cooler hoses from the clip.
6.3. Gently, pull the oil cooler pipe fittings straight out from the radiator quick connect fittings.
6.4. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair > Page 3652
7. If equipped with a 8.1. engine, perform the following:
7.1. Remove the oil cooler hoses from the clip.
7.2. Gently, pull the oil cooler pipe fittings straight out from the radiator quick connect fittings.
7.3. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information.
8. It equipped, remove the engine shield bolts. 9. Remove the engine shield.
10. If equipped with the a 6.0L engine, perform the following:
10.1. Remove the oil cooler hose bracket bolt (1).
10.2. Remove the oil cooler hose adapter bolts (2).
10.3. Remove the oil cooler hose assembly and gasket. Discard the gasket.
10.4. Inspect the fittings, connectors and cooler hoses for damage or distortion.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair > Page 3653
11. If equipped with a 8.1. engine, perform the following:
11.1. Remove the oil cooler hose bracket bolt.
11.2. Disconnect the quick connect fittings (1) at the engine.
11.3. Remove the oil cooler hose assembly. Discard the gasket.
11.4. Inspect the fittings, connectors and cooler hoses for damage or distortion.
Installation Procedure
Important: A distinct snap should be heard when assembling tube ends of the hose assembly to
quick connectors. To ensure tube is fully inserted into the connector, check by giving tube a forceful
pull.
1. If equipped with a 8.1. engine, perform the following:
1.1. Remove the oil cooler hose assembly.
1.2. Connect the quick connect fittings (1) at the engine.
Notice: Refer to Fastener Notice in Cautions and Notices.
1.3. Install the oil cooler hose bracket bolt.
- Tighten the bolt to 50 Nm (37 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair > Page 3654
2. If equipped with a 6.0L engine, perform the following:
2.1. Install the oil cooler hose assembly and a new gasket.
2.2. Install the oil cooler hose adapter bolts (2).
- Tighten the bolts to 12 Nm (106 inch lbs.).
2.3. Install the oil cooler hose bracket bolt (1).
- Tighten the bolt to 25 Nm (18 ft. lbs.).
3. If equipped, install the engine shield. 4. Install the engine shield bolts.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
5. Do not install the new retaining clip onto the fitting by pushing on the clip.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair > Page 3655
Important: Failure to properly install the retaining clip could cause the cooler line to come loose and
cause damage to the engine.
6. Install the NEW retaining clip into the quick connect fitting by using your thumb and forefinger.
Insert the new retaining clip into one of the three
fitting recesses. Ensure that the retaining clip is engaged in all 3 slots.
7. With one end of the retaining clip engaged in the connector fitting slot, use your thumb in order
to rotate the retaining clip around the connector
fitting, until the retaining clip snaps into place.
8. Ensure that the 3 retaining clip ears are seen from inside the fitting and that the retaining clip
moves freely in the fitting slots. 9. Install a new retaining clip into the remaining quick connect
fitting.
10. If equipped with a 6.01L engine, perform the following:
10.1. Install the oil cooler hoses to the hose clip on the fan shroud.
10.2. Snap the oil cooler hose clip shut.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Line, Engine >
Component Information > Service and Repair > Page 3656
Important: Ensure the oil cooler line being installed has a plastic cap on the end that connects to the quick
connect fitting. If no plastic cap exists, or the plastic cap is damaged, obtain a new cap. Install the
cap on to the cooler line prior to cooler line installation.
- Do not use the plastic cap in order to install the cooler line into the fitting.
11. If equipped with a 8.1. engine, perform the following:
11.1. Install the oil cooler hoses to the clip.
11.2. Install the oil cooler lines to the radiator. Install the cooler line straight into the quick connect
fitting. Insert the cooler line end into the quick connect fitting until a click is either heard or felt.
11.3. Pull back sharply on the cooler line in order to ensure that the cooler line is installed in the
quick connect fitting.
Important: Do not manually depress the retaining clip when installing the plastic cap.
12. Snap the plastic cap onto the quick connect fitting. 13. Ensure that the plastic cap is fully
seated against the fitting.
14. Ensure that no gap is present between the cap and the fitting.
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15. Ensure that the yellow identification band on the tube is hidden within the quick connect fitting.
A hidden yellow identification band indicates
proper joint seating.
16. Run the engine. Inspect the engine oil cooling system for leaks. 17. Inspect the engine oil level.
Add oil if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pan, Engine >
Component Information > Specifications > Fastener Tightening Specifications
Oil Pan: Specifications Fastener Tightening Specifications
Oil Pan Drain Plug ...............................................................................................................................
..................................................... 25 Nm (18 ft. lbs.) Oil Pan Bolt ......................................................
........................................................................................................................................ 25 Nm (18 ft.
lbs.)
To Front Cover ....................................................................................................................................
................................................. 25 Nm (18 ft. lbs.) To Rear Cover .....................................................
............................................................................................................................... 12 Nm (106 in.
lbs.)
Oil Pan Skid Plate Bolt ........................................................................................................................
..................................................... 20 Nm (15 ft. lbs.) Oil Pan Cover Bolts ..........................................
.................................................................................................................................. 12 Nm (106 inch
lbs.) Oil Pan Drain Plug .......................................................................................................................
............................................................. 25 Nm (18 ft. lbs.)
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Component Information > Specifications > Fastener Tightening Specifications > Page 3662
Oil Pan: Specifications Engine Mechanical Specifications (Unit Repair)
Oil Pan and Front/Rear Cover Alignment
Oil Pan to Rear of Engine Block Alignment (at Transmission Bellhousing Mounting Surface)
........................... 0.0-0.25 mm (Maximum) (0.0-0.01 inch
(Maximum))
Front Cover Alignment (at Oil Pan Surface)
............................................................................................................................... 0.0-0.5 mm
(0.0-0.02 inch) Rear Cover Alignment (at Oil Pan Surface)
................................................................................................................................ 0.0-0.5 mm
(0.0-0.02 inch)
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pan, Engine >
Component Information > Service and Repair > Oil Pan Replacement
Oil Pan: Service and Repair Oil Pan Replacement
Oil Pan Replacement
Removal Procedure
1. If equipped with four wheel drive (4WD), remove the front differential. 2. Remove the starter
motor. 3. Remove the engine shield bolts. 4. Remove the engine shield.
5. If equipped, remove the oil pan skid plate bolts. 6. Remove the oil pan skid plate.
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7. Remove the crossbar bolts. 8. Remove the crossbar.
9. Remove the transmission cover bolt and cover.
10. Drain the engine oil and remove the engine oil filter. 11. Re-install the drain plug and oil filter
until snug.
12. If equipped with the 4L60-E automatic transmission, remove the transmission bolt and stud on
the right side.
13. Remove the bottom bolt on the left side.
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14. If equipped with the 4L80-E automatic transmission, remove the transmission converter cover
bolts.
15. Disconnect the oil level sensor electrical connector (6).
16. Remove the battery cable channel bolt. 17. Slide the channel pin out of the oil pan tab.
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18. Remove the following from the positive battery cable clip:
- Engine wiring harness clip
- Positive battery cable clip
19. Remove the engine oil cooler lines from the positive battery cable clip. 20. Remove the positive
battery cable clip bolt and clip.
21. Remove the oil pan bolts. 22. Remove the oil pan.
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Important: DO NOT allow foreign material to enter the oil passages of the oil pan, cap or cover the
openings as required.
23. Drill (3) out the oil pan gasket retaining rivets (2), if required. 24. Remove the gasket (1) from
the pan. 25. Discard the gasket and rivets. 26. Clean and inspect the engine oil pan.
Installation Procedure
Important: The alignment of the structural oil pan is critical. The rear bolt hole locations of the oil pan provide
mounting points for the transmission bellhousing. To ensure the rigidity of the powertrain and
correct transmission alignment, it is important that the rear of the block and the rear of the oil pan
must NEVER protrude beyond the engine block and transmission bellhousing plane.
- Do not reuse the oil pan gasket.
- It is not necessary to rivet the NEW gasket to the oil pan.
1. Apply a 5 mm (0.20 inch) bead of sealant GM U.S. P/N 12378190, or equivalent 20 mm (0.80
inch) long to the engine block. Apply the sealant
directly onto the tabs of the front cover gasket that protrudes into the oil pan surface.
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2. Apply a 5 mm (0.20 inch) bead of sealant GM U.S. P/N 12378190, or equivalent 20 mm (0.8
inch) long to the engine block. Apply the sealant
directly onto the tabs of the rear cover gasket that protrudes into the oil pan surface.
Important: Be sure to align the oil gallery passages in the oil pan and engine block properly with the
oil pan gasket.
3. Pre-assemble the oil pan gasket to the pan.
- Install the gasket onto the pan.
- Install the oil pan bolts to the pan and through the gasket.
4. Install the oil pan, gasket and bolts to the engine block. 5. Tighten the oil pan bolts until snug. Do
not overtighten.
6. Install the transmission converter cover bolts until snug, if equipped with the 4L80-E automatic
transmission.
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7. Install the transmission bolt and stud on the right side until snug, If equipped with the 4L60-E
automatic transmission.
Notice: Refer to Fastener Notice in Service Precautions.
8. Install the bottom bolt on the left side until snug.
8.1. Tighten the oil pan and oil pan-to-oil pan front cover bolts to 25 Nm (18 ft. lbs.).
8.2. Tighten the oil pan-to-rear cover bolts to 12 Nm (106 inch lbs.).
8.3. Tighten the bellhousing, converter cover. and transmission bolts/stud to 50 Nm (37 ft. lbs.).
9. Install the positive battery cable clip and bolt to the oil pan.
- Tighten the positive battery cable clip bolt to 9 Nm (80 inch lbs.).
10. Install the engine oil cooler lines to the positive battery cable clip.
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11. Install the following to the positive battery cable clip:
- Engine wiring harness clip
- Positive battery cable clip
12. Slide the channel pin in to the oil pan tab. 13. Install the battery cable channel bolt.
- Tighten the battery cable channel bolt to 12 Nm (106 inch lbs.).
14. Connect the oil level sensor electrical connector (6).
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15. Install the transmission cover and bolt.
- Tighten the transmission cover bolt to 12 Nm (106 inch lbs.).
16. Install the crossbar. 17. Install the crossbar bolts.
- Tighten the crossbar bolts to 100 Nm (74 ft. lbs.).
18. If equipped, install the oil pan skid plate. 19. Install the oil pan skid plate bolts.
- Tighten the oil pan skid plate bolts to 20 Nm (15 ft. lbs.).
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20. Install the engine shield. 21. Install the engine shield bolts.
- Tighten the engine shield bolts to 20 Nm (15 ft. lbs.).
22. Install the starter motor. 23. If equipped with 4WD, install the front differential. 24. Install new
engine oil and a new oil filter.
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Oil Pan: Service and Repair Oil Pan Cover Replacement
Oil Pan Cover Replacement
Removal Procedure
1. Drain the engine oil. 2. Remove the oil pan cover bolts (1), cover (2), and gasket (3). 3. Discard
the gasket.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install a new oil pan cover gasket (3), the cover (2) and bolts (1).
- Tighten the oil pan cover bolts to 12 Nm (106 inch lbs.).
2. Refill the engine oil.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions
Oil Pressure Gauge: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 3679
Electrical Symbols Part 1
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Component Information > Diagrams > Diagram Information and Instructions > Page 3680
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3681
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3682
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3683
Oil Pressure Gauge: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3702
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3703
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3704
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3705
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3706
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3707
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3708
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Diagram Information and Instructions > Page 3709
Oil Pressure Gauge: Electrical Diagrams
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Diagrams.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Page 3710
Oil Pressure Gauge: Description and Operation
ENGINE OIL PRESSURE GAGE
The IPC uses the engine oil sensor signal to determine the engine oil pressure. The oil pressure
sensor signal circuit is hard-wired to the IPC. The engine oil pressure sensor signal to the IPC is a
variable resistance ranging from 0-90 Ohms. The sensor resistance is used to drive the engine oil
pressure gage. A sensor resistance of 1 Ohm will display as 0 kPa (0 psi) and a resistance of 88
Ohms will display as 550 kPa (80 psi). The IPC monitors the oil pressure sensor signal circuit in
order to decide when the oil pressure is too low. The Check Engine Oil Pressure indicator will be
displayed in the message center if the IPC detects a low engine oil pressure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Gauge >
Component Information > Diagrams > Page 3711
Oil Pressure Gauge: Testing and Inspection
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Testing and Inspection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Sender >
Component Information > Diagrams
Engine Oil Pressure (EOP) Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Sender >
Component Information > Diagrams > Page 3715
Oil Pressure Sender: Service and Repair
Engine Oil Pressure Sensor and/or Switch Replacement
- Tools Required J 41712 Oil Pressure Sensor Socket
Removal Procedure
1. If necessary, remove the engine sight shield. 2. Disconnect the oil pressure sensor electrical
connector (1).
3. Using J 41712 or equivalent, remove the oil pressure sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pressure Sender >
Component Information > Diagrams > Page 3716
1. Apply sealant GM U.S. P/N 12346004, Canada P/N 10953480, or equivalent, to the threads of
the oil pressure sensor.
Notice: Refer to Fastener Notice in Service Precautions.
2. Using J 41712 or equivalent, install the oil pressure sensor.
- Tighten the oil pressure sensor to 20 Nm (15 ft. lbs.).
3. Connect the oil pressure sensor electrical connector (1). 4. If necessary, install the engine sight
shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pump Cover >
Component Information > Specifications
Oil Pump Cover: Specifications
Oil Pump Cover Bolts ..........................................................................................................................
............................................... 12 Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Customer Interest for Oil Pick Up/Strainer: > 02-06-01-038 > Dec >
02 > Engine - Knocking or Lifter Noise
Oil Pick Up/Strainer: Customer Interest Engine - Knocking or Lifter Noise
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-038
Date: December, 2002
TECHNICAL
Subject: Engine Knock or Lifter Noise (Replace 0-Ring)
Models: 2001-2002 Chevrolet Camaro 2001-2003 Chevrolet Corvette 2001-2002 Pontiac Firebird
2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Suburban, Tahoe 2001-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 2000-2003 GMC Yukon, Yukon XL
2001-2003 GMC Sierra with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, Z, G, S, N, U - RPOs
LR4, LM7, L59, LS1, LS6, LQ9, LQ4)
Condition
Some customers may comment on an engine tick noise. The distinguishing characteristic of this
condition is that it likely will have been present since new, and is typically noticed within the first
161-322 km (100-200 mi). The noise may often be diagnosed as a collapsed lifter. Additionally, the
noise may be present at cold start and appear to diminish and then return as the engine warms to
operating temperature. This noise is different from other noises that may begin to occur at
3219-4828 km (2000-3000 mi).
Cause
The 0-ring seal between the oil pump screen and the oil pump may be cut, causing aeration of the
oil.
Correction
Inspect the 0-ring seal and replace as necessary. Use the applicable part number listed below.
Refer to the Engine Mechanical sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSP0.
Warranty Information
For vehicles repaired under warranty, use the table shown.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Customer Interest for Oil Pick Up/Strainer: > 02-06-01-038 > Dec >
02 > Engine - Knocking or Lifter Noise > Page 3728
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Oil Pick Up/Strainer: >
02-06-01-038 > Dec > 02 > Engine - Knocking or Lifter Noise
Oil Pick Up/Strainer: All Technical Service Bulletins Engine - Knocking or Lifter Noise
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-01-038
Date: December, 2002
TECHNICAL
Subject: Engine Knock or Lifter Noise (Replace 0-Ring)
Models: 2001-2002 Chevrolet Camaro 2001-2003 Chevrolet Corvette 2001-2002 Pontiac Firebird
2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Suburban, Tahoe 2001-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 2000-2003 GMC Yukon, Yukon XL
2001-2003 GMC Sierra with 4.8L, 5.3L, 5.7L or 6.0L V8 Engine (VINs V, T, Z, G, S, N, U - RPOs
LR4, LM7, L59, LS1, LS6, LQ9, LQ4)
Condition
Some customers may comment on an engine tick noise. The distinguishing characteristic of this
condition is that it likely will have been present since new, and is typically noticed within the first
161-322 km (100-200 mi). The noise may often be diagnosed as a collapsed lifter. Additionally, the
noise may be present at cold start and appear to diminish and then return as the engine warms to
operating temperature. This noise is different from other noises that may begin to occur at
3219-4828 km (2000-3000 mi).
Cause
The 0-ring seal between the oil pump screen and the oil pump may be cut, causing aeration of the
oil.
Correction
Inspect the 0-ring seal and replace as necessary. Use the applicable part number listed below.
Refer to the Engine Mechanical sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSP0.
Warranty Information
For vehicles repaired under warranty, use the table shown.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Oil Pick Up/Strainer: >
02-06-01-038 > Dec > 02 > Engine - Knocking or Lifter Noise > Page 3734
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Page 3735
Oil Pick Up/Strainer: Specifications
Oil Pump Screen Nut ...........................................................................................................................
..................................................... 25 Nm (18 ft. lbs.) Oil Pump Screen Bolt .......................................
................................................................................................................................... 12 Nm (106
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Page 3736
Oil Pick Up/Strainer: Service and Repair
Oil Pumps, Pump Screen and Deflector Replacement
Removal Procedure
1. Remove the oil pan. 2. Remove the engine front cover. 3. Remove the oil pump screen bolt and
nuts. 4. Remove the oil pump screen with O-ring seal. 5. Remove the O-ring seal from the pump
screen. 6. Discard the O-ring seal.
7. Remove the remaining crankshaft oil deflector nuts. 8. Remove the crankshaft oil deflector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Page 3737
9. Remove the oil pump bolts.
Important: Do not allow dirt or debris to enter the oil pump assembly, cap end as necessary.
10. Remove the oil pump. 11. Clean and inspect the oil pump.
Installation Procedure
1. Align the splined surfaces of the crankshaft sprocket and the oil pump drive gear and install the
oil pump. 2. Install the oil pump onto the crankshaft sprocket until the pump housing contacts the
face of the engine block.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the oil pump bolts.
- Tighten the oil pump bolts to 25 Nm (18 ft. lbs.).
4. Install the crankshaft oil deflector and nuts until snug.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pick Up/Strainer >
Component Information > Technical Service Bulletins > Page 3738
5. Lubricate a NEW oil pump screen O-ring seal with clean engine oil. 6. Install the NEW O-ring
seal onto the oil pump screen.
Important: Push the oil pump screen tube completely into the oil pump prior to tightening the bolt.
Do not allow the bolt to pull the tube into the pump.
7. Align the oil pump screen mounting brackets with the correct crankshaft bearing cap studs. 8.
Install the oil pump screen. 9. Install the oil pump screen bolt and nuts.
9.1. Tighten the oil pump screen bolt to 12 Nm (106 inch lbs.).
9.2. Tighten the crankshaft oil deflector/oil pump screen nuts to 25 Nm (18 ft. lbs.).
10. Install the engine front cover. 11. Install the oil pan.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pump, Engine > Engine
Oil Pressure > Component Information > Specifications
Engine Oil Pressure: Specifications
Oil Pressure Minimum - Hot
At 1,000 Revolutions Per Minute (RPM)
...................................................................................................................................................... 41
kPa (6 psig) At 2,000 RPM ..................................................................................................................
.......................................................................... 124 kPa (18 psig) At 4,000 RPM ..............................
..............................................................................................................................................................
165 kPa (24 psig)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pump, Engine > Engine
Oil Pressure > Component Information > Specifications > Page 3743
Engine Oil Pressure: Testing and Inspection
Oil Pressure Diagnosis and Testing
- Tools Required J 21867 Pressure Gauge
- J 42907 Oil Pressure Testing Tool
1. With the vehicle on a level surface, run the vehicle for a few minutes, allow adequate drain down
time, 2-3 minutes, and measure the oil level. 2. If required, add the recommended grade engine oil
and fill the crankcase until the oil level measures full on the oil level indicator. 3. Run the engine
briefly, 10-15 seconds, and verify low or no oil pressure on the vehicle gauge or light. 4. Listen for a
noisy valve train or a knocking noise. 5. Inspect for the following:
- Oil diluted by water or glycol anti freeze
- Foamy oil
6. Remove the oil filter and install the J 42907. 7. install J21867 or equivalent to the J42907. 8. Run
the engine and measure the engine oil pressure. 9. Compare the readings to Engine Mechanical
Specifications.
10. If the engine oil pressure is below specifications, inspect the engine for one or more of the
following:
- Oil pump worn or dirty.
- Oil pump-to-engine block bolts loose.
- Oil pump screen loose, plugged, or damaged
- Oil pump screen O-ring seal missing or damaged
- Malfunctioning oil pump pressure regulator valve
- Excessive bearing clearance
- Cracked, porous, or restricted oil galleries
- Oil gallery plugs missing or incorrectly installed.
- Broken valve lifters Repair as necessary
11. If the oil pressure reading on the J 21867 or equivalent is within specifications, inspect for the
following:
- Plugged or incorrect oil filter and/or malfunctioning oil bypass valve
- Malfunctioning oil pressure gauge or sensor Repair as necessary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Engine Lubrication > Oil Pump, Engine > Oil
Pressure Regulator Valve > Component Information > Specifications
Oil Pressure Regulator Valve: Specifications
Oil Pump Relief Valve Plug .................................................................................................................
............................................... 12 Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes - 'Reduced Brake Power' Shown on
DIC
Intake Manifold: Customer Interest Brakes - 'Reduced Brake Power' Shown on DIC
File In Section: 05 - Brakes
Bulletin No.: 02-05-23-004
Date: October, 2002
TECHNICAL
Subject: Driver's Information Center (DIC) "Reduced Brake Power" Message, Reduced Vacuum
Boost (Inspect/Replace Intake Manifold and Recalibrate the Instrument Panel Cluster (IPC))
Models: 2002-2003 Cadillac Escalade 2WD 2002-2003 Chevrolet Avalanche 1500 Series,
Silverado, Suburban, Tahoe 2002-2003 GMC Sierra, Yukon, Yukon XL with Power Vacuum Boost
Brake System (RPOs JC3 and JC4)
Condition Some customers may comment on a "Reduced Brake Power" message on the DIC.
Cause It is possible that a very small number of 2002 and 2003 model year vehicles may have a
restriction in the vacuum booster port on the intake manifold. On the 2003 model year, only the IPC
calibration is the cause of the DIC message.
Correction Important:
Only inspect suspect vehicles built between June 13, 2002 and August 9, 2002.
Follow the service procedure to diagnose and correct this condition.
1. Open the hood and install fender covers.
2. Loosen the engine sight shield bolt. The bolt should stay in the shield.
3. Remove the engine sight shield from the sight shield retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes - 'Reduced Brake Power' Shown on
DIC > Page 3755
4. Inspect the left front corner of the intake manifold for a "C" with a circle around it (2). ^
If the intake manifold DOES have a "C" (2) on it, continue with Step 5.
^ If the intake manifold DOES NOT have a "C" (2) on it, continue with Step 19.
5. Disconnect the accelerator control cable clip from the engine sight shield retainer.
6. Disconnect the cruise control cable clip from the retainer if equipped.
7. Remove the engine sight shield retainer bolts and the retainer if equipped.
8. Inspect rear center of the intake manifold just below the recycle symbol for "MADE IN CANADA"
(2). ^
If the intake manifold DOES have "MADE IN CANADA" (1) on it, continue with Step 9
^ If the intake manifold DOES NOT have "MADE IN CANADA" (1) on it, continue with Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes - 'Reduced Brake Power' Shown on
DIC > Page 3756
9. Locate the vacuum booster port connector (1) on the left rear of the intake manifold.
10. Gently pull out on the vacuum booster hose (2).
11. With two fingers, push in the vacuum booster port connector lock ring (3) while gently pulling
out on the vacuum booster hose (2).
Important:
^ DO NOT force the drill bit into the vacuum booster intake port.
^ If the vacuum booster intake port is restricted, DO NOT attempt to remove the restriction with the
drill bit.
^ If the restriction is removed with the drill bit, the material from the restriction may cause internal
engine damage.
^ If the vacuum booster port is restricted, the intake manifold must be replaced.
12. Inspect the vacuum booster intake port with a 8.7 mm (11/32 in) drill bit, maximum length of
127 mm (5 in).
13. Insert the drill bit approximately 63.5 mm (2.5 in) into the vacuum booster intake port.
^ If the vacuum booster intake port IS restricted, continue with Step 14.
^ If the vacuum booster intake port IS NOT restricted, continue with Step 15.
14. Replace the intake manifold. Refer to Intake Manifold Replacement (SI Document ID #
753666).
15. Reinstall the vacuum booster hose to the vacuum booster intake port by pushing to hose nipple
into the connector.
16. Install the engine sight shield retainer and the bolts.
Tighten
Tighten the engine sight shield retainer bolts to 5 N.m (44 lb in).
17. Install the cruise control cable clip to the retainer.
18. Install the accelerator control cable clip to the retainer if equipped.
19. Install the engine sight shield to the retainer if equipped.
Tighten
Tighten the engine sight shield bolt to 10 N.m (89 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes - 'Reduced Brake Power' Shown on
DIC > Page 3757
20. Start the engine and fully apply the brakes four or five times in order to ensure a "good" brake
pedal.
Recalibrating the IPC (2003 Model Year Vehicles)
1. Vehicles Built Prior To the following VIN Breakpoints
^ 3G104569
^ 3E117608
^ 31118369
^ 3Z120443
^ 3R107568
^ 3J101720
2. Plug in Tech 2.
3. Set the parking brake and turn the ignition ON with the engine off.
4. Reprogram the IPC following normal SPS procedures (TIS Version 9 released August 2002 or
newer).
5. After reprogramming the IPC, start the vehicle and fully apply the brakes four to five times in
order to ensure a "good" brake pedal and that there are no messages on the DIC.
Important:
The Owner's Manual Must Be Replaced After The IPC Is Recalibrated.
^ A new Owner's Manual can be ordered from Helm @ 1-800-551-4123. The dealer will be billed
for the new Manual and reimbursed through the warranty claims system.
^ The Owner's Manual will be shipped to the dealer. Dealers will be required to mail the Manual to
the customer.
Parts Information Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > Customer Interest: > 02-05-23-004 > Oct > 02 > Brakes - 'Reduced Brake Power' Shown on
DIC > Page 3758
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 00-06-01-026C > Feb > 10 > Engine Intake Manifold Inspection/Replacement
Intake Manifold: All Technical Service Bulletins Engine - Intake Manifold Inspection/Replacement
INFORMATION
Bulletin No.: 00-06-01-026C
Date: February 03, 2010
Subject: Intake Manifold Inspection/Replacement After Severe Internal Engine Damage
Models:
2010 and Prior Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2, H3
2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to include additional model years. Please discard
Corporate Bulletin Number 00-06-01-026B (Section 06 - Engine).
When replacing an engine due to internal damage, extreme care should be taken when transferring
the intake manifold to the new Goodwrench service engine long block. Internal damage may result
in the potential discharge of internal engine component debris in the intake manifold via broken
pistons and/or bent, broken, or missing intake valves. After removing the intake manifold from the
engine, the technician should carefully inspect all of the cylinder head intake ports to see if the
valve heads are still present and not bent. Usually when the valve heads are missing or sufficiently
bent, internal engine component debris will be present to varying degrees in the intake port of the
cylinder head. If this debris is present in any of the cylinder head intake ports, the intake manifold
should be replaced. This replacement is required due to the complex inlet runner and plenum
configuration of most of the intake manifolds, making thorough and complete component cleaning
difficult and nearly impossible to verify complete removal of debris. Re-installation of an intake
manifold removed from an engine with deposits of internal engine component debris may result in
the ingestion of any remaining debris into the new Goodwrench service engine. This may cause
damage or potential failure of the new service engine.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC
Intake Manifold: All Technical Service Bulletins Brakes - 'Reduced Brake Power' Shown on DIC
File In Section: 05 - Brakes
Bulletin No.: 02-05-23-004
Date: October, 2002
TECHNICAL
Subject: Driver's Information Center (DIC) "Reduced Brake Power" Message, Reduced Vacuum
Boost (Inspect/Replace Intake Manifold and Recalibrate the Instrument Panel Cluster (IPC))
Models: 2002-2003 Cadillac Escalade 2WD 2002-2003 Chevrolet Avalanche 1500 Series,
Silverado, Suburban, Tahoe 2002-2003 GMC Sierra, Yukon, Yukon XL with Power Vacuum Boost
Brake System (RPOs JC3 and JC4)
Condition Some customers may comment on a "Reduced Brake Power" message on the DIC.
Cause It is possible that a very small number of 2002 and 2003 model year vehicles may have a
restriction in the vacuum booster port on the intake manifold. On the 2003 model year, only the IPC
calibration is the cause of the DIC message.
Correction Important:
Only inspect suspect vehicles built between June 13, 2002 and August 9, 2002.
Follow the service procedure to diagnose and correct this condition.
1. Open the hood and install fender covers.
2. Loosen the engine sight shield bolt. The bolt should stay in the shield.
3. Remove the engine sight shield from the sight shield retainer.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 3768
4. Inspect the left front corner of the intake manifold for a "C" with a circle around it (2). ^
If the intake manifold DOES have a "C" (2) on it, continue with Step 5.
^ If the intake manifold DOES NOT have a "C" (2) on it, continue with Step 19.
5. Disconnect the accelerator control cable clip from the engine sight shield retainer.
6. Disconnect the cruise control cable clip from the retainer if equipped.
7. Remove the engine sight shield retainer bolts and the retainer if equipped.
8. Inspect rear center of the intake manifold just below the recycle symbol for "MADE IN CANADA"
(2). ^
If the intake manifold DOES have "MADE IN CANADA" (1) on it, continue with Step 9
^ If the intake manifold DOES NOT have "MADE IN CANADA" (1) on it, continue with Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 3769
9. Locate the vacuum booster port connector (1) on the left rear of the intake manifold.
10. Gently pull out on the vacuum booster hose (2).
11. With two fingers, push in the vacuum booster port connector lock ring (3) while gently pulling
out on the vacuum booster hose (2).
Important:
^ DO NOT force the drill bit into the vacuum booster intake port.
^ If the vacuum booster intake port is restricted, DO NOT attempt to remove the restriction with the
drill bit.
^ If the restriction is removed with the drill bit, the material from the restriction may cause internal
engine damage.
^ If the vacuum booster port is restricted, the intake manifold must be replaced.
12. Inspect the vacuum booster intake port with a 8.7 mm (11/32 in) drill bit, maximum length of
127 mm (5 in).
13. Insert the drill bit approximately 63.5 mm (2.5 in) into the vacuum booster intake port.
^ If the vacuum booster intake port IS restricted, continue with Step 14.
^ If the vacuum booster intake port IS NOT restricted, continue with Step 15.
14. Replace the intake manifold. Refer to Intake Manifold Replacement (SI Document ID #
753666).
15. Reinstall the vacuum booster hose to the vacuum booster intake port by pushing to hose nipple
into the connector.
16. Install the engine sight shield retainer and the bolts.
Tighten
Tighten the engine sight shield retainer bolts to 5 N.m (44 lb in).
17. Install the cruise control cable clip to the retainer.
18. Install the accelerator control cable clip to the retainer if equipped.
19. Install the engine sight shield to the retainer if equipped.
Tighten
Tighten the engine sight shield bolt to 10 N.m (89 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 3770
20. Start the engine and fully apply the brakes four or five times in order to ensure a "good" brake
pedal.
Recalibrating the IPC (2003 Model Year Vehicles)
1. Vehicles Built Prior To the following VIN Breakpoints
^ 3G104569
^ 3E117608
^ 31118369
^ 3Z120443
^ 3R107568
^ 3J101720
2. Plug in Tech 2.
3. Set the parking brake and turn the ignition ON with the engine off.
4. Reprogram the IPC following normal SPS procedures (TIS Version 9 released August 2002 or
newer).
5. After reprogramming the IPC, start the vehicle and fully apply the brakes four to five times in
order to ensure a "good" brake pedal and that there are no messages on the DIC.
Important:
The Owner's Manual Must Be Replaced After The IPC Is Recalibrated.
^ A new Owner's Manual can be ordered from Helm @ 1-800-551-4123. The dealer will be billed
for the new Manual and reimbursed through the warranty claims system.
^ The Owner's Manual will be shipped to the dealer. Dealers will be required to mail the Manual to
the customer.
Parts Information Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Intake Manifold: > 02-05-23-004 > Oct > 02 > Brakes 'Reduced Brake Power' Shown on DIC > Page 3771
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Technical Service Bulletins > All Other Service Bulletins for Intake Manifold: > 00-06-01-026C > Feb > 10 > Engine - Intake
Manifold Inspection/Replacement
Intake Manifold: All Technical Service Bulletins Engine - Intake Manifold Inspection/Replacement
INFORMATION
Bulletin No.: 00-06-01-026C
Date: February 03, 2010
Subject: Intake Manifold Inspection/Replacement After Severe Internal Engine Damage
Models:
2010 and Prior Passenger Cars and Trucks (Including Saturn) 2010 and Prior HUMMER H2, H3
2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to include additional model years. Please discard
Corporate Bulletin Number 00-06-01-026B (Section 06 - Engine).
When replacing an engine due to internal damage, extreme care should be taken when transferring
the intake manifold to the new Goodwrench service engine long block. Internal damage may result
in the potential discharge of internal engine component debris in the intake manifold via broken
pistons and/or bent, broken, or missing intake valves. After removing the intake manifold from the
engine, the technician should carefully inspect all of the cylinder head intake ports to see if the
valve heads are still present and not bent. Usually when the valve heads are missing or sufficiently
bent, internal engine component debris will be present to varying degrees in the intake port of the
cylinder head. If this debris is present in any of the cylinder head intake ports, the intake manifold
should be replaced. This replacement is required due to the complex inlet runner and plenum
configuration of most of the intake manifolds, making thorough and complete component cleaning
difficult and nearly impossible to verify complete removal of debris. Re-installation of an intake
manifold removed from an engine with deposits of internal engine component debris may result in
the ingestion of any remaining debris into the new Goodwrench service engine. This may cause
damage or potential failure of the new service engine.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Specifications > Engine Mechanical Specifications (Unit Repair)
Intake Manifold: Specifications Engine Mechanical Specifications (Unit Repair)
Intake Manifold
Intake Manifold Cylinder Head Deck Flatness (Measured within a 200 mm (7.87 inch)Area that
Includes Two Runner Port Openings). .............. 0.3 mm
(0.118 inch)
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Specifications > Engine Mechanical Specifications (Unit Repair) > Page 3779
Intake Manifold: Specifications Fastener Tightening Specifications
Intake Manifold Bolt
First Pass in Sequence ........................................................................................................................
................................................. 5 Nm (44 inch lbs.) Final Pass in Sequence ......................................
................................................................................................................................ 10 Nm (89 inch
lbs.)
Intake Manifold Sight Shield Bolt (RPO LQ9 - 6.0L Engine)
................................................................................................................ 9 Nm (80 inch lbs.) Intake
Manifold Sight Shield Bolt (4.8L, 5.3L, and RPO LQ4)
............................................................................................................ 10 Nm (89 inch lbs.) Intake
Manifold Sight Shield Retainer Bolt
............................................................................................................................................ 5 Nm (44
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement
Intake Manifold: Service and Repair Engine Sight Shield Replacement
Engine Sight Shield Replacement (4.8L, 5.3L, and 6.0L (LQ4)
Removal Procedure
1. Loosen the intake manifold sight shield bolt. 2. Remove the sight shield from the sight shield
retainer.
3. If removal of the sight shield retainer is required, disconnect the accelerator control cable clip
from the retainer.
4. Disconnect the cruise control cable clip from the retainer. 5. Remove the sight shield retainer
bolts and the retainer, if required.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3782
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the sight shield retainer and the bolts, if required.
- Tighten the retainer bolts to 5 Nm (44 inch lbs.).
2. Install the cruise control cable clip to the retainer.
3. Install the accelerator control cable clip to the retainer.
Notice: Use care when installing the engine sight shield to avoid contacting the manifold absolute
pressure (MAP) sensor wire harness connector. Loss of engine performance or engine damage
may result. 4. Install the intake manifold sight shield to the retainer.
- Tighten the bolt to 10 Nm (89 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3783
Intake Manifold: Service and Repair Intake Manifold Replacement
Intake Manifold Replacement
Removal Procedure
Important: The intake manifold, throttle body, fuel rail, and injectors may be removed as an
assembly. If not servicing the individual components, remove the manifold as a complete
assembly.
1. Remove the throttle body. 2. Remove the fuel injectors. 3. Disconnect the following electrical
connectors:
- Manifold absolute pressure (MAP) sensor (1)
- Knock sensor (2)
- Exhaust gas recirculation (EGR) valve, if equipped.
4. Remove the knock sensor harness electrical connector from the intake manifold. 5. Set the
electrical harness aside.
6. If equipped, remove the following EGR pipe bolts:
- Intake manifold (1)
- Cylinder head (2)
- Exhaust manifold (3)
7. If equipped, remove the EGR pipe with valve. 8. If equipped, remove the EGR pipe gasket from
the exhaust manifold.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3784
9. If equipped with vacuum assisted brakes, remove the vacuum brake booster hose from the rear
of the intake manifold.
10. Remove the positive crankcase ventilation (PCV) hose with valve.
11. Remove the MAP sensor (1) from the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3785
12. Remove the accelerator control cable bracket bolts (1). 13. Remove the accelerator control
cable bracket (2) from the intake manifold.
14. Remove the evaporative emission (EVAP) purge solenoid vent tube by performing the
following:
14.1. Remove the EVAP tube end (2) from the solenoid (1).
14.2. Squeeze the EVAP pipe quick connect fitting (3) retainer together.
14.3. Remove the EVAP tube end (3) from the vapor pipe.
15. Remove the EVAP purge solenoid bolt (2), solenoid (3), and isolator (1) from the intake
manifold.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3786
16. Remove the intake manifold bolts. 17. Remove the intake manifold.
18. Remove the intake manifold gaskets (1) from the intake manifold. 19. Discard the old intake
manifold gaskets. 20. Clean and inspect the intake manifold. 21. If equipped with EGR, clean the
gasket surfaces of the EGR pipe and the exhaust manifold.
Installation Procedure
1. Install new intake manifold gaskets (1) to the intake manifold.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3787
2. Install the intake manifold. 3. Apply a 5 mm (0.20 inch) band of threadlock GM U.S. P/N
12345382, Canada P/N 10953489, or equivalent to the threads of the intake manifold
bolts.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the intake manifold bolts.
4.1. Tighten the intake manifold bolts a first pass in sequence to 5 Nm (44 inch lbs.).
4.2. Tighten the intake manifold bolts a final pass in sequence to 10 Nm (89 inch lbs.).
5. install the EVAP purge solenoid (3), isolator (1), and bolt (2) to the intake manifold.
- Tighten the EVAP purge solenoid bolt to 10 Nm (89 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Intake Manifold > Component Information >
Service and Repair > Engine Sight Shield Replacement > Page 3788
6. Install the EVAP purge solenoid vent tube to the solenoid (1) and vapor pipe.
7. Install the accelerator control cable bracket (2) to the intake manifold. 8. Install the accelerator
control cable bracket bolts (1).
- Tighten the accelerator control cable bracket bolts to 10 Nm (89 inch lbs.).
Important: Lightly coat the MAP sensor seal with clean engine oil before installing.
9. Install the MAP sensor (1) to the intake manifold.
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Service and Repair > Engine Sight Shield Replacement > Page 3789
10. Install the PCV hose with valve.
11. If equipped with vacuum assisted brakes, install the vacuum brake booster hose to the rear of
the intake manifold.
12. If equipped, position a new EGR pipe gasket on the exhaust manifold. 13. If equipped, install
the EGR pipe with valve. 14. If equipped, install the following EGR pipe bolts until snug:
- Intake manifold (1)
- Cylinder head (2)
- Exhaust manifold (3)
15. If equipped, tighten the EGR pipe bolts.
- Tighten the EGR valve pipe-to-intake manifold bolts to 10 Nm (89 inch lbs.).
- Tighten the EGR valve pipe-to-cylinder head bolts to 50 Nm (37 ft. lbs.).
- Tighten the EGR valve pipe-to-exhaust manifold bolts to 30 Nm (22 ft. lbs.).
16. Route the electrical harness into position over the engine.
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17. Connect the knock sensor harness electrical connector to the intake manifold. 18. Connect the
following electrical connectors.
- MAP sensor (1)
- Knock sensor (2)
- EGR valve, if equipped
19. Install the fuel injectors. 20. Install the throttle body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions
Oil Pressure Gauge: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3796
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3797
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3798
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3799
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3800
Oil Pressure Gauge: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3801
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3802
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3813
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3814
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3815
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3816
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3817
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3818
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3819
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3820
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3821
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3822
Equivalents - Decimal And Metric Part 1
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Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3823
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3824
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3825
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 3826
Oil Pressure Gauge: Electrical Diagrams
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Diagrams.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Page 3827
Oil Pressure Gauge: Description and Operation
ENGINE OIL PRESSURE GAGE
The IPC uses the engine oil sensor signal to determine the engine oil pressure. The oil pressure
sensor signal circuit is hard-wired to the IPC. The engine oil pressure sensor signal to the IPC is a
variable resistance ranging from 0-90 Ohms. The sensor resistance is used to drive the engine oil
pressure gage. A sensor resistance of 1 Ohm will display as 0 kPa (0 psi) and a resistance of 88
Ohms will display as 550 kPa (80 psi). The IPC monitors the oil pressure sensor signal circuit in
order to decide when the oil pressure is too low. The Check Engine Oil Pressure indicator will be
displayed in the message center if the IPC detects a low engine oil pressure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Lamps and Indicators - Engine > Oil Pressure
Gauge > Component Information > Diagrams > Page 3828
Oil Pressure Gauge: Testing and Inspection
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Testing and Inspection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Crankshaft Main
Bearing Seal > Component Information > Specifications
Crankshaft Main Bearing Seal: Specifications
Crankshaft Oil Deflector Nuts ..............................................................................................................
.................................................... 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Crankshaft Main
Bearing Seal > Component Information > Specifications > Page 3833
Crankshaft Main Bearing Seal: Service and Repair
Crankshaft Rear Oil Seal Replacement
- Tools Required J 41479 Crankshaft Rear Oil Seal Installer
Removal Procedure
1. Remove the engine flywheel.
2. Remove the crankshaft rear oil seal (1) from the rear cover.
Installation Procedure
Important: The flywheel spacer (if applicable) must be removed prior to oil seal installation.
- Do not lubricate the oil seal inside diameter (ID) or the crankshaft surface.
- Do not reuse the crankshaft rear oil seal.
1. Lubricate the outside diameter (OD) of the oil seal (1) with clean engine oil. DO NOT allow oil or
other lubricants to contact the seal surface. 2. Lubricate the rear cover oil seal bore with clean
engine oil. DO NOT allow oil or other lubricants to contact the crankshaft surface.
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Bearing Seal > Component Information > Specifications > Page 3834
3. Install the J 41479 tapered cone (2) and bolts onto the rear of the crankshaft. 4. Tighten the bolts
until snug. Do not overtighten. 5. Install the rear oil seal onto the tapered cone (2) and push the
seal to the rear cover bore. 6. Thread the J 41479 threaded rod into the tapered cone until the tool
(1) contacts the oil seal. 7. Align the oil seal into the tool (1). 8. Rotate the handle of the tool (1)
clockwise until the seal enters the rear cover and bottoms into the cover bore. 9. Remove the J
41479.
10. Install the engine flywheel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Exhaust Manifold
Gasket > Component Information > Service and Repair
Exhaust Manifold Gasket: Service and Repair
Exhaust Seal Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Remove the engine shield bolts and shield, if necessary.
3. Remove the oil pan skid plate bolts and plate, if necessary.
4. Disconnect the CPA retainer. 5. Disconnect the oxygen sensor electrical connector (1). 6.
Support the catalytic converter or exhaust manifold pipe with adjustable jackstands.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Exhaust Manifold
Gasket > Component Information > Service and Repair > Page 3838
7. Remove the right exhaust manifold pipe nuts.
8. Remove the left exhaust manifold pipe nuts. 9. Remove the exhaust hanger mounting bracket
bolts.
10. Lower the catalytic converter or exhaust manifold pipe using the adjustable jackstands. 11.
Remove the exhaust manifold pipe seal(s).
Installation Procedure
1. Install the exhaust manifold pipe seal(s). 2. Raise the catalytic converter or exhaust manifold
pipe using the adjustable jackstands. 3. Install the exhaust hanger mounting bracket bolts.
Notice: Refer to Fastener Notice in Cautions and Notices.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Exhaust Manifold
Gasket > Component Information > Service and Repair > Page 3839
4. Install the left exhaust manifold pipe nuts.
- Tighten the transmission bolts to 100 Nm (74 ft. lbs.).
- Tighten the exhaust pipe hanger bracket bolts to 12 Nm (106 inch lbs.).
- Tighten the exhaust manifold pipe nuts to 50 Nm (39 ft. lbs.).
5. Install the right exhaust manifold pipe nuts.
- Tighten the nuts to 50 Nm (39 ft. lbs.).
6. Connect the oxygen sensor electrical connector (1). 7. Connect the CPA retainer. 8. Remove the
adjustable jackstands from catalytic converter or exhaust manifold pipe.
9. Install the oil pan skid plate and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Exhaust Manifold
Gasket > Component Information > Service and Repair > Page 3840
10. Install the engine shield and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
11. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Front Crankshaft
Seal > Component Information > Service and Repair
Front Crankshaft Seal: Service and Repair
Crankshaft Front Oil Seal Replacement
- Tools Required J 41478 Crankshaft Front Oil Seal Installer
Removal Procedure
1. Remove the crankshaft balancer.
2. Remove the crankshaft oil seal (1) from the front cover.
Installation Procedure
Important: Do not lubricate the oil seal sealing surface.
- Do not reuse the crankshaft oil seal.
1. Lubricate the outer edge of the oil seal (1) with clean engine oil. 2. Lubricate the front cover oil
seal bore with clean engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Front Crankshaft
Seal > Component Information > Service and Repair > Page 3844
3. Install the crankshaft front oil seal onto the J 41478 guide. 4. Install the J 41478 threaded rod
(with nut, washer, guide, and oil seal) into the end of the crankshaft. 5. Use the J41478 in order to
install the oil seal into the cover bore.
5.1. Use a wrench and hold the hex on the installer bolt.
5.2. Use a second wrench and rotate the installer nut clockwise until the seal bottoms in the cover
bore.
5.3. Remove the J41478.
5.4. Inspect the oil seal for proper installation. The oil seal should be installed evenly and
completely into the front cover bore.
6. Install the crankshaft balancer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > Customer Interest: > 05-06-04-029A > Jun > 05 > Engine Rough Idle/Misfire/MIL ON/DTC P0300
Intake Manifold Gasket: Customer Interest Engine - Rough Idle/Misfire/MIL ON/DTC P0300
Bulletin No.: 05-06-04-029A
Date: June 24, 2005
TECHNICAL
Subject: Flexible Fuel (RPO L59) Rough Idle, Misfire, MIL DTC P0300 (Install Intake Manifold
Gaskets With Teal Green Gasket Material)
Models: 2002-2004 Chevrolet Silverado, Suburban, Tahoe 2002-2004 GMC Sierra, Yukon, Yukon
XL with 5.3L Engine and Flexible Fuel (VIN Z - RPO L59)
This bulletin may apply to the following engines using regular fuel: 4.8L, 5.3L, 6.0L (VINs V, T, P,
U, N - RPOs LR4, LM7, LM4, LQ4, LQ9).
Supercede:
This bulletin is being revised to add additional diagnostic information. Please discard Corporate
Bulletin Number 05-06-04-029 (Section 06 - Engine/Propulsion System).
Important:
Always begin your diagnosis with the Diagnostic System Check - Engine Controls (SI Document ID
# 1289827) for any MIL or driveability concern. The Diagnostic System Check directs you to the
next logical step in your diagnosis. Follow the instructions in this bulletin should the rough idle,
misfire, or DTC P0300 diagnostic procedure point to an air leak in the intake manifold gasket.
Following the published diagnostic procedures will improve diagnostic accuracy and support our fix
it right the first time approach.
Condition
Some customers may comment that the vehicle may have a rough idle, misfires and/or a MIL
illuminated with a stored DTC P0300.
Cause
The L59 engine is calibrated for ethanol fuel (E85). Due to the low volatility of ethanol, the PCM
provides higher fuel flow through the injector, which may pool on the upper manifold to head gasket
material. Overtime (usually 12 months and longer), the gasket material may degrade resulting in an
unmetered air leak.
Correction
Replace the upper intake manifold gaskets with the teal green gasket material, P/N 89017589.
Important:
Do not replace the upper intake manifold gaskets with the original orange gasket material, P/N
17113557.
Inspect Intake Manifold to Cylinder head Deck for Warpage
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Gasket > Component Information > Technical Service Bulletins > Customer Interest: > 05-06-04-029A > Jun > 05 > Engine Rough Idle/Misfire/MIL ON/DTC P0300 > Page 3853
Important:
The intake plenum should also be checked for excessive warpage that may cause an uneven
clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced.
Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a
200 mm (7.87 in) area should be replaced." Intake warpage is measured at the gasket sealing
surfaces and should be measured within a 200 mm (7.87 in) area. This measurement is across
only two of the intake runner port openings. Measurements taken across the entire distance of all
four intake runner ports will lead to unnecessary manifold replacements.
Important:
Measurements taken across the entire distance of all four intake runner ports will lead to
unnecessary intake manifold replacements.
1. Locate a straight edge across the intake manifold cylinder head deck surface. Position the
straight edge across two runner port openings.
2. Insert a feeler gauge between the intake manifold and the straight edge. An intake manifold with
warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be
replaced. Do not replace intake manifolds with warpage that measures less than 3 mm (0.118 in)
over a 200 mm (7.87 in).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
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Disclaimer
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 05-06-04-029A > Jun >
05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300
Intake Manifold Gasket: All Technical Service Bulletins Engine - Rough Idle/Misfire/MIL ON/DTC
P0300
Bulletin No.: 05-06-04-029A
Date: June 24, 2005
TECHNICAL
Subject: Flexible Fuel (RPO L59) Rough Idle, Misfire, MIL DTC P0300 (Install Intake Manifold
Gaskets With Teal Green Gasket Material)
Models: 2002-2004 Chevrolet Silverado, Suburban, Tahoe 2002-2004 GMC Sierra, Yukon, Yukon
XL with 5.3L Engine and Flexible Fuel (VIN Z - RPO L59)
This bulletin may apply to the following engines using regular fuel: 4.8L, 5.3L, 6.0L (VINs V, T, P,
U, N - RPOs LR4, LM7, LM4, LQ4, LQ9).
Supercede:
This bulletin is being revised to add additional diagnostic information. Please discard Corporate
Bulletin Number 05-06-04-029 (Section 06 - Engine/Propulsion System).
Important:
Always begin your diagnosis with the Diagnostic System Check - Engine Controls (SI Document ID
# 1289827) for any MIL or driveability concern. The Diagnostic System Check directs you to the
next logical step in your diagnosis. Follow the instructions in this bulletin should the rough idle,
misfire, or DTC P0300 diagnostic procedure point to an air leak in the intake manifold gasket.
Following the published diagnostic procedures will improve diagnostic accuracy and support our fix
it right the first time approach.
Condition
Some customers may comment that the vehicle may have a rough idle, misfires and/or a MIL
illuminated with a stored DTC P0300.
Cause
The L59 engine is calibrated for ethanol fuel (E85). Due to the low volatility of ethanol, the PCM
provides higher fuel flow through the injector, which may pool on the upper manifold to head gasket
material. Overtime (usually 12 months and longer), the gasket material may degrade resulting in an
unmetered air leak.
Correction
Replace the upper intake manifold gaskets with the teal green gasket material, P/N 89017589.
Important:
Do not replace the upper intake manifold gaskets with the original orange gasket material, P/N
17113557.
Inspect Intake Manifold to Cylinder head Deck for Warpage
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Important:
The intake plenum should also be checked for excessive warpage that may cause an uneven
clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced.
Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a
200 mm (7.87 in) area should be replaced." Intake warpage is measured at the gasket sealing
surfaces and should be measured within a 200 mm (7.87 in) area. This measurement is across
only two of the intake runner port openings. Measurements taken across the entire distance of all
four intake runner ports will lead to unnecessary manifold replacements.
Important:
Measurements taken across the entire distance of all four intake runner ports will lead to
unnecessary intake manifold replacements.
1. Locate a straight edge across the intake manifold cylinder head deck surface. Position the
straight edge across two runner port openings.
2. Insert a feeler gauge between the intake manifold and the straight edge. An intake manifold with
warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be
replaced. Do not replace intake manifolds with warpage that measures less than 3 mm (0.118 in)
over a 200 mm (7.87 in).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
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Gasket > Component Information > Technical Service Bulletins > All Technical Service Bulletins: > 05-06-04-029A > Jun >
05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300 > Page 3861
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Staining/Pitting/Corrosion
INFORMATION
Bulletin No.: 00-03-10-002F
Date: April 21, 2011
Subject: Chemical Staining, Pitting, Corrosion and/or Spotted Appearance of Chromed Aluminum
Wheels
Models:
2012 and Prior GM Cars and Trucks
Supercede: This bulletin is being revised to update model years, suggest additional restorative
products and add additional corrosion information. Please discard Corporate Bulletin Number
00-03-10-002E (Section 03 - Suspension). Important You may give a copy of this bulletin to the
customer.
What is Chemical Staining of Chrome Wheels? Figure 1
Chemical staining in most cases results from acid based cleaners (refer to Figure 1 for an
example). These stains are frequently milky, black, or greenish in appearance. They result from
using cleaning solutions that contain acids on chrome wheels. Soap and water is usually sufficient
to clean wheels.
If the customer insists on using a wheel cleaner they should only use one that specifically states
that it is safe for chromed wheels and does not contain anything in the following list. (Dealers
should also survey any products they use during prep or normal cleaning of stock units for these
chemicals.)
- Ammonium Bifluoride (fluoride source for dissolution of chrome)
- Hydrofluoric Acid (directly dissolves chrome)
- Hydrochloric Acid (directly dissolves chrome)
- Sodium Dodecylbenzenesulfonic Acid
- Sulfamic Acid
- Phosphoric Acid
- Hydroxyacetic Acid
Notice
Many wheel cleaner instructions advise to take care to avoid contact with painted surfaces. Most
customers think of painted surfaces as the fenders, quarter panels and other exterior sheet metal.
Many vehicles have painted brake calipers. Acidic wheel cleaners may craze, crack, or discolor the
paint on the brake calipers. Damage from wheel cleaners is not covered under the vehicle new car
warranty. Soap and water applied with a soft brush is usually all that is required to clean the
calipers.
Whenever any wheel cleaner is used, it must be THOROUGHLY rinsed off of the wheel with clean,
clear water. Special care must be taken to rinse under the hub cap, balance weights, wheel nuts,
lug nut caps, between the wheel cladding and off the back side of the wheel. Wheels returned to
the Warranty Parts Center (WPC) that exhibit damage from wheel cleaners most often have the
damage around and under the wheel weight where the cleaner was incompletely flushed away.
Notice
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00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3867
Do not use cleaning solutions that contain hydrofluoric, oxalic and most other acids on chrome
wheels (or any wheels).
If the customer is unsure of the chemical make-up of a particular wheel cleaner, it should be
avoided.
For wheels showing signs of milky staining from acidic cleaners, refer to Customer Assistance and
Instructions below.
Warranty of Stained Chrome Wheels
Stained wheels are not warrantable. Most acid based cleaners will permanently stain chrome
wheels. Follow-up with dealers has confirmed that such cleaners were used on wheels that were
returned to the Warranty Parts Center (WPC). Any stained wheels received by the WPC will be
charged back to the dealership. To assist the customer, refer to Customer Assistance and
Instructions below.
Pitting or Spotted Appearance of Chrome Wheels Figure 2
A second type or staining or finish disturbance may result from road chemicals, such as calcium
chloride used for dust control of unpaved roads. The staining will look like small pitting (refer to
Figure 2). This staining will usually be on the leading edges of each wheel spoke, but may be
uniformly distributed. If a vehicle must be operated under such conditions, the chrome wheels
should be washed with mild soap and water and thoroughly rinsed as soon as conveniently
possible.
Important Road chemicals, such as calcium chloride used for dust control of unpaved roads, can
also stain chrome wheels. The staining will look like small pitting. This staining will usually be on
the leading edges of each wheel spoke. This is explained by the vehicle traveling in the forward
direction while being splashed by the road chemical. If a vehicle must be operated under such
conditions, the chrome wheels should be washed with mild soap and water and thoroughly rinsed
as soon as conveniently possible.
Warranty of Pitted or Spotted Chrome Wheels
Wheels returned with pitting or spotting as a result of road chemicals may be replaced one time.
Damage resulting from contact with these applied road chemicals is corrosive to the wheels finish
and may cause damage if the wheels are not kept clean.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean if they are operating the vehicle in an area that
applies calcium chloride or other dust controlling chemicals! "GM of Canada" dealers require prior
approval by the District Manager - Customer Care and Service Process (DM-CCSP).
"Stardust" Corrosion of Chrome Wheels Figure 3
A third type of finish disturbance results from prolonged exposure to brake dust and resultant
penetration of brake dust through the chrome. As brakes are applied hot particles of brake material
are thrown off and tend to be forced through the leading edge of the wheel spoke windows by
airflow. These
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00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3868
hot particles embed themselves in the chrome layer and create a small pit. If the material is allowed
to sit on the wheel while it is exposed to moisture or salt, it will corrode the wheel beneath the
chrome leaving a pit or small blister in the chrome.
Heavy brake dust build-up should be removed from wheels by using GM Chrome Cleaner and
Polish, P/N 1050173 (in Canada use 10953013). For moderate cleaning, light brake dust build-up
or water spots use GM Swirl Remover Polish, P/N 12377965 (in Canada, use Meguiars
Plast-X(TM) Clear Plastic Cleaner and Polish #G12310C**). After cleaning, the wheel should be
waxed using GM Cleaner Wax, P/N 12377966 (in Canada, use Meguiars Cleaner Wax
#M0616C**), which will help protect the wheel from brake dust and reduce adhesion of any brake
dust that gets on the wheel surface. For general maintenance cleaning, PEEK Metal Polish† may
be used. It will clean and shine the chrome and leave behind a wax coating that may help protect
the finish.
Warranty of Stardust Corroded Chrome Wheels
Wheels returned with pitting or spotting as a result of neglect and brake dust build-up may be
replaced one time.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean and free of prolonged exposure to brake dust
build-up. "GM of Canada" dealers require prior approval by the District Manager - Customer Care
and Service Process (DM-CCSP).
Customer Assistance and Instructions
GM has looked for ways customers may improve the appearance of wheels damaged by acidic
cleaners. The following product and procedure has been found to dramatically improve the
appearance of stained wheels. For wheels that have milky stains caused by acidic cleaners try the
following:
Notice
THE 3M CHROME AND METAL POLISH REQUIRED FOR THIS PROCEDURE IS AN
EXTREMELY AGGRESSIVE POLISH/CLEANER. THE WHEELS MUST BE CLEANED BEFORE
APPLICATION TO AVOID SCRATCHING THE WHEEL SURFACE. THIS PRODUCT WILL
REDUCE THE THICKNESS OF THE CHROME PLATING ON THE WHEEL AND IF USED
INCORRECTLY OR EXCESSIVELY MAY REMOVE THE CHROME PLATING ALL TOGETHER,
EXPOSING A LESS BRIGHT AND BRASSY COLORED SUB-LAYER. FOLLOW INSTRUCTIONS
EXACTLY.
1. Wash the wheels with vigorously with soap and water. This step will clean and may reduce
wheel staining. Flood all areas of the wheel with water
to rinse.
2. Dry the wheels completely.
Notice Begin with a small section of the wheel and with light pressure buff off polish and examine
results. ONLY apply and rub with sufficient force and time to remove enough staining that you are
satisfied with the results. Some wheels may be stained to the extent that you may only achieve a
50% improvement while others may be able to be restored to the original lustre. IN ALL CASES,
only apply until the results are satisfactory.
3. Apply 3M Chrome and Metal Polish #39527* with a clean terry cloth towel. As you apply the
polish, the staining will be diminished. 4. When dry, buff off the polish with a clean portion of the
towel. 5. Repeat application of the 3M Chrome and Metal Polish until satisfied with the results. If
continued applications fail to improve the appearance
further discontinue use.
This procedure will improve the appearance of the wheels and may, with repeated applications,
restore the finish dramatically. For wheels that exhibit spotting from road chemicals the above
procedure may marginally improve the condition but will not restore the finish or remove the pitting.
In this type of staining the wheel finish has actually been removed in spots and no manner of
cleaning will restore the finish.
†*We believe this source and their products to be reliable. There may be additional manufacturers
of such products/materials. General Motors does not endorse, indicate any preference for or
assume any responsibility for the products or material from this firm or for any such items that may
be available from other sources.
Parts Information
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00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3869
*This product is currently available from 3M. To obtain information for your local retail location
please call 3M at 1-888-364-3577.
**This product is currently available from Meguiars (Canada). To obtain information for your local
retail location please call Meguiars at 1-800-347-5700 or at www.meguiarscanada.com.
^ This product is currently available from Tri-Peek International. To obtain information for your local
retail location please call Tri-Peek at
1-877-615-4272 or at www.tripeek.com.
Disclaimer
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99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum Wheels
Wheels: All Technical Service Bulletins Wheels/Tires - Refinishing Aluminum Wheels
INFORMATION
Bulletin No.: 99-08-51-007E
Date: March 17, 2011
Subject: Refinishing Aluminum Wheels
Models:
2012 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add additional model years. Please discard Corporate
Bulletin Number 99-08-51-007D (Section 08 - Body and Accessories).
This bulletin updates General Motor's position on refinishing aluminum wheels. GM does not
endorse any repairs that involve welding, bending, straightening or re-machining. Only cosmetic
refinishing of the wheel's coatings, using recommended procedures, is allowed.
Evaluating Damage
In evaluating damage, it is the GM Dealer's responsibility to inspect the wheel for corrosion,
scrapes, gouges, etc. The Dealer must insure that such damage is not deeper than what can be
sanded or polished off. The wheel must be inspected for cracks. If cracks are found, discard the
wheel. Any wheels with bent rim flanges must not be repaired or refinished. Wheels that have been
refinished by an outside company must be returned to the same vehicle. The Dealer must record
the wheel ID stamp or the cast date on the wheel in order to assure this requirement. Refer to
Refinisher's Responsibility - Outside Company later in this bulletin.
Aluminum Wheel Refinishing Recommendations
- Chrome-plated aluminum wheels Re-plating these wheels is not recommended.
- Polished aluminum wheels These wheels have a polyester or acrylic clearcoat on them. If the
clearcoat is damaged, refinishing is possible. However, the required refinishing process cannot be
performed in the dealer environment. Refer to Refinisher's Responsibility - Outside Company later
in this bulletin.
- Painted aluminum wheels These wheels are painted using a primer, color coat, and clearcoat
procedure. If the paint is damaged, refinishing is possible. As with polished wheels, all original
coatings must be removed first. Media blasting is recommended. Refer to GM Aluminum
Refinishing Bulletin #53-17-03A for the re-painting of this type of wheel.
- Bright, machined aluminum wheels These wheels have a polyester or acrylic clearcoat on them.
In some cases, the recessed "pocket" areas of the wheel may be painted. Surface refinishing is
possible. The wheel must be totally stripped by media blasting or other suitable means. The wheel
should be resurfaced by using a sanding process rather than a machining process. This allows the
least amount of material to be removed.
Important Do not use any re-machining process that removes aluminum. This could affect the
dimensions and function of the wheel.
Painting is an option to re-clearcoating polished and bright machined aluminum wheels. Paint will
better mask any surface imperfections and is somewhat more durable than clearcoat alone. GM
recommends using Corsican SILVER WAEQ9283 for a fine "aluminum-like" look or Sparkle
SILVER WA9967 for a very bright look. As an option, the body color may also be used. When using
any of the painting options, it is recommended that all four wheels be refinished in order to maintain
color uniformity. Refer to GM Aluminum Refinishing Bulletin #53-17-03A for specific procedures
and product recommendations.
Refinisher's Responsibility - Outside Company
Important Some outside companies are offering wheel refinishing services. Such refinished wheels
will be permanently marked by the refinisher and are warranted by the refinisher. Any process that
re-machines or otherwise re-manufactures the wheel should not be used.
A refinisher's responsibility includes inspecting for cracks using the Zyglo system or the equivalent.
Any cracked wheels must not be refinished. No welding, hammering or reforming of any kind is
allowed. The wheel ID must be recorded and follow the wheel throughout the process in order to
assure that the same wheel is returned. A plastic media blast may be used for clean up of the
wheel. Hand and/or lathe sanding of the machined surface and the wheel window is allowed.
Material removal, though, must be kept to a minimum. Re-machining of the wheel is not allowed.
Paint and/or clear coat must not be present on the following surfaces: the nut chamfers, the wheel
mounting surfaces and the wheel pilot hole. The refinisher must permanently ID stamp the wheel
and warrant the painted/clearcoated surfaces for a minimum of one year or the remainder of the
new vehicle warranty, whichever is
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99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum Wheels > Page 3874
longer.
Important Whenever a wheel is refinished, the mounting surface and the wheel nut contact
surfaces must not be painted or clearcoated. Coating these surfaces could affect the wheel nut
torque.
When re-mounting a tire on an aluminum wheel, coated balance weights must be used in order to
reduce the chance of future cosmetic damage.
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
06-03-10-010A > Jun > 10 > Wheels - Changing Procedures/Precautions
Wheels: All Technical Service Bulletins Wheels - Changing Procedures/Precautions
INFORMATION
Bulletin No.: 06-03-10-010A
Date: June 09, 2010
Subject: Information on Proper Wheel Changing Procedures and Cautions
Models:
2011 and Prior GM Passenger Cars and Trucks 2010 and Prior HUMMER Models 2005-2009 Saab
9-7X 2005-2009 Saturn Vehicles
Attention:
Complete wheel changing instructions for each vehicle line can be found under Tire and Wheel
Removal and Installation in Service Information (SI). This bulletin is intended to quickly review and
reinforce simple but vital procedures to reduce the possibility of achieving low torque during wheel
installation. Always refer to SI for wheel lug nut torque specifications and complete jacking
instructions for safe wheel changing.
Supercede: This bulletin is being revised to include the 2011 model year and update the available
special tool list. Please discard Corporate Bulletin Number 06-03-10-010 (Section 03 Suspension).
Frequency of Wheel Changes - Marketplace Driven
Just a few years ago, the increasing longevity of tires along with greater resistance to punctures
had greatly reduced the number of times wheels were removed to basically required tire rotation
intervals. Today with the booming business in accessory wheels/special application tires (such as
winter tires), consumers are having tire/wheel assemblies removed - replaced - or installed more
than ever. With this increased activity, it opens up more of a chance for error on the part of the
technician. This bulletin will review a few of the common concerns and mistakes to make yourself
aware of.
Proper Servicing Starts With the Right Tools
The following tools have been made available to assist in proper wheel and tire removal and
installation.
- J 41013 Rotor Resurfacing Kit (or equivalent)
- J 42450-A Wheel Hub Resurfacing Kit (or equivalent)
Corroded Surfaces
One area of concern is corrosion on the mating surfaces of the wheel to the hub on the vehicle.
Excessive corrosion, dirt, rust or debris built up on these surfaces can mimic a properly tightened
wheel in the service stall. Once the vehicle is driven, the debris may loosen, grind up or be washed
away from water splash. This action may result in clearance at the mating surface of the wheel and
an under-torqued condition.
Caution
Before installing a wheel, remove any buildup on the wheel mounting surface and brake drum or
brake disc mounting surface. Installing wheels with poor metal-to-metal contact at the mounting
surfaces can cause wheel nuts to loosen. This may cause a wheel to come off when the vehicle is
moving, possibly resulting in a loss of control or personal injury.
Whenever you remove the tire/wheel assemblies, you must inspect the mating surfaces. If
corrosion is found, you should remove the debris with a die grinder equipped with a fine sanding
pad, wire brush or cleaning disc. Just remove enough material to assure a clean, smooth mating
surface.
The J 41013 (or equivalent) can be used to clean the following surfaces:
- The hub mounting surface
- The brake rotor mounting surface
- The wheel mounting surface
Use the J 42450-A (or equivalent) to clean around the base of the studs and the hub.
Lubricants, Grease and Fluids
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06-03-10-010A > Jun > 10 > Wheels - Changing Procedures/Precautions > Page 3879
Some customers may use penetrating oils, grease or other lubricants on wheel studs to aid in
removal or installation. Always use a suitable cleaner/solvent to remove these lubricants prior to
installing the wheel and tire assemblies. Lubricants left on the wheel studs may cause improper
readings of wheel nut torque. Always install wheels to clean, dry wheel studs ONLY.
Notice
Lubricants left on the wheel studs or vertical mounting surfaces between the wheel and the rotor or
drum may cause the wheel to work itself loose after the vehicle is driven. Always install wheels to
clean, dry wheel studs and surfaces ONLY. Beginning with 2011 model year vehicles, put a light
coating of grease, GM P/N 1051344 (in Canada, P/N 9930370), on the inner surface of the wheel
pilot hole to prevent wheel seizure to the axle or bearing hub.
Wheel Stud and Lug Nut Damage
Always inspect the wheel studs and lug nuts for signs of damage from crossthreading or abuse.
You should never have to force wheel nuts down the stud. Lug nuts that are damaged may not
retain properly, yet give the impression of fully tightening. Always inspect and replace any
component suspected of damage.
Tip
Always start wheel nuts by hand! Be certain that all wheel nut threads have been engaged
BEFORE tightening the nut.
Important If the vehicle has directional tread tires, verify the directional arrow on the outboard side
of the tire is pointing in the direction of forward rotation.
Wheel Nut Tightening and Torque
Improper wheel nut tightening can lead to brake pulsation and rotor damage. In order to avoid
additional brake repairs, evenly tighten the wheel nuts to the proper torque specification as shown
for each vehicle in SI. Always observe the proper wheel nut tightening sequence as shown below in
order to avoid trapping the wheel on the wheel stud threads or clamping the wheel slightly off
center resulting in vibration.
The Most Important Service You Provide
While the above information is well known, and wheel removal so common, technicians run the risk
of becoming complacent on this very important
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service operation. A simple distraction or time constraint that rushes the job may result in personal
injury if the greatest of care is not exercised. Make it a habit to double check your work and to
always side with caution when installing wheels.
Disclaimer
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00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV)
Wheels: All Technical Service Bulletins Wheels/Tires - Tire Radial Force Variation (RFV)
INFORMATION
Bulletin No.: 00-03-10-006F
Date: May 04, 2010
Subject: Information on Tire Radial Force Variation (RFV)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks 2010 and Prior HUMMER H2, H3 2009
and Prior Saab 9-7X 2000-2005 Saturn L Series 2003-2007 Saturn ION
Supercede: This bulletin is being revised to considerably expand the available information on
Radial Force Variation (RFV) and should be reviewed in whole. Please discard Corporate Bulletin
Number 00-03-10-006E (Section 03 - Suspension).
Important
- Before measuring tires on equipment such as the Hunter GSP9700, the vehicle MUST be driven
a minimum of 16 km (10 mi) to ensure removal of any flat-spotting. Refer to Corporate Bulletin
Number 03-03-10-007E - Tire/Wheel Characteristics of GM Original Equipment Tires.
- Equipment such as the Hunter GSP9700 MUST be calibrated prior to measuring tire/wheel
assemblies for each vehicle.
The purpose of this bulletin is to provide guidance to GM dealers when using tire force variation
measurement equipment, such as the Hunter GSP9700. This type of equipment can be a valuable
tool in diagnosing vehicle ride concerns. The most common ride concern involving tire radial force
variation is highway speed shake on smooth roads.
Tire related smooth road highway speed shake can be caused by three conditions: imbalance, out
of round and tire force variation. These three conditions are not necessarily related. All three
conditions must be addressed.
Imbalance is normally addressed first, because it is the simpler of the three to correct. Off-vehicle,
two plane dynamic wheel balancers are readily available and can accurately correct any
imbalance. Balancer calibration and maintenance, proper attachment of the wheel to the balancer,
and proper balance weights, are all factors required for a quality balance. However, a perfectly
balanced tire/wheel assembly can still be "oval shaped" and cause a vibration.
Before balancing, perform the following procedures.
Tire and Wheel Diagnosis
1. Set the tire pressure to the placard values. 2. With the vehicle raised, ensure the wheels are
centered on the hub by loosening all wheel nuts and hand-tightening all nuts first by hand while
shaking the wheel, then torque to specifications using a torque wrench, NOT a torque stick.
3. Visually inspect the tires and the wheels. Inspect for evidence of the following conditions and
correct as necessary:
- Missing balance weights
- Bent rim flange
- Irregular tire wear
- Incomplete bead seating
- Tire irregularities (including pressure settings)
- Mud/ice build-up in wheel
- Stones in the tire tread
- Remove any aftermarket wheels and/or tires and restore vehicle to original condition prior to
diagnosing a smooth road shake condition.
4. Road test the vehicle using the Electronic Vibration Analyzer (EVA) essential tool. Drive for a
sufficient distance on a known, smooth road
surface to duplicate the condition. Determine if the vehicle is sensitive to brake apply. If the brakes
are applied lightly and the pulsation felt in the steering wheel increases, refer to the Brakes section
of the service manual that deals with brake-induced pulsation. If you can start to hear the vibration
as a low boom noise (in addition to feeling it), but cannot see it, the vehicle likely has a first order
(one pulse per propshaft revolution) driveline vibration. Driveline first order vibrations are high
enough in frequency that most humans can start to hear them at highway speeds, but are too high
to be able to be easily seen. These issues can be caused by driveline imbalance or misalignment.
If the vehicle exhibits this low boom and the booming pulses in-and-out on a regular basis (like a
throbbing), chances are good that the vehicle could have driveline vibration. This type
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00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3885
of vibration is normally felt more in the "seat of the pants" than the steering wheel.
5. Next, record the Hertz (Hz) reading as displayed by the EVA onto the tire data worksheet found
at the end of this bulletin. This should be done
after a tire break-in period of at least 16 km (10 mi) at 72 km/h (45 mph) or greater, in order to
eliminate any possible tire flat-spotting. This reading confirms what the vehicle vibration frequency
is prior to vehicle service and documents the amount of improvement occurring as the result of the
various steps taken to repair. Completing the Steering Wheel Shake Worksheet below is required.
A copy of the completed worksheet must be saved with the R.O. and a copy included with any
parts returned to the Warranty Parts Center for analysis. A reading of 35 to 50 Hz typically
indicates a first order propshaft vibration. If this is the situation, refer to Corporate Bulletin Number
08-07-30-044D. Generally, a reading between 10 and 20 Hz indicates a tire/wheel vibration and if
this is the reading obtained, continue using this bulletin. If the tire 1st order vibration goes away
and stays away during this evaluation, the cause is likely tire flat-spotting. Tire flat-spotting vibration
may come and go at any speed over 72 km/h (45 mph) during the first 10 minutes of operation, if
vibration continues after 10 minutes of driving at speeds greater than 72 km/h (45 mph), tire
flat-spotting can be ruled out as the cause for vibration.
6. If flat-spotting is the cause, provide the explanation that this has occurred due to the vehicle
being parked for long periods of time and that the
nature of the tire is to take a set. Refer to Corporate Bulletin Number 03-03-10-007E: Information
on Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment
Tires.
7. If the road test indicates a shake/vibration exists, check the imbalance of each tire/wheel
assembly on a known, calibrated, off-car dynamic
balancer.Make sure the mounting surface of the wheel and the surface of the balancer are
absolutely clean and free of debris. Be sure to chose the proper cone/collet for the wheel, and
always use the pilot bore for centering. Never center the wheel using the hub-cap bore since it is
not a precision machined surface. If any assembly calls for more than 1/4 ounce on either rim
flange, remove all balance weights and rebalance to as close to zero as possible. If you can see
the vibration (along with feeling it) in the steering wheel (driving straight without your hands on the
wheel), it is very likely to be a tire/wheel first order (one pulse per revolution) disturbance. First
order disturbances can be caused by imbalance as well as non-uniformities in tires, wheels or
hubs. This first order frequency is too low for a human to hear, but if the amplitude is high enough,
it can be seen.
If a vibration or shake still exists after balancing, any out of round conditions, of the wheel, and
force variation conditions of the tire, must be addressed. Equipment such as the Hunter GSP9700
can address both (it is also a wheel balancer).
Tire radial force vibration (RFV) can be defined as the amount of stiffness variation the tire will
produce in one revolution under a constant load. Radial force variation is what the vehicle feels
because the load (weight) of the vehicle is always on the tires. Although free runout of tires (not
under load) is not always a good indicator of a smooth ride, it is critical that total tire/wheel
assembly runout be within specification.
Equipment such as the Hunter GSP9700 loads the tire, similar to on the vehicle, and measures
radial force variation of the tire/wheel assembly. Note that the wheel is affecting the tire's RFV
measurement at this point. To isolate the wheel, its runout must be measured. This can be easily
done on the Hunter, without the need to set up dial indicators. If the wheel meets the runout
specification, the tire's RFV can then be addressed.
After measuring the tire/wheel assembly under load, and the wheel alone, the machine then
calculates (predicts) the radial force variation of the tire. However, because this is a prediction that
can include mounting inaccuracies, and the load wheel is much smaller in diameter than used in
tire production, this type of service equipment should NOT be used to audit new tires. Rather, it
should be used as a service diagnostic tool to minimize radial force variation of the tire/wheel
assembly.
Equipment such as the Hunter GSP9700 does an excellent job of measuring wheel runout, and of
finding the low point of the wheel (for runout) and the high point of the tire (for radial force
variation). This allows the tire to be matched mounted to the wheel for lowest tire/wheel assembly
force variation.
The machine will simplify this process into easy steps. The following assembly radial force variation
numbers should be used as a guide:
When measuring RFV and match mounting tires perform the following steps.
Measuring Wheel Runout and Assembly Radial Force Variation
Important The completed worksheet at the end of this bulletin must be attached to the hard copy of
the repair order.
- Measure radial force variation and radial runout.
- If a road force/balancing machine is used, record the radial force variation (RFV) on the
worksheet at the end of this bulletin. It may be of benefit to have the lowest RFV assembly to the
front left corner. If the machine is not available and the EVA data suggests there is an issue, swap
the tire and wheel assemblies from the front to the back. Re-check on the EVA and if the problem
still exists, test another vehicle to find tires that do not exhibit the same frequency and swap those
tires onto the subject vehicle.
- If a runout/balancing machine is used, record the radial runout of the tire/wheel assemblies on the
worksheet at the end of this bulletin. If one or more of the tire/wheel assemblies are more than.040
in (1.02 mm), match mount the tire to the wheel to get below.040 in (1.02 mm). For sensitive
customers, readings of 0.030 inch (0.76 mm) or less are preferable, it may also be of benefit to
have the lowest runout assembly to the front left corner. If the machine is not available and the
EVA data suggests there is an issue, swap the tire and wheel assemblies from the front to the
back. Re-check on the EVA and if the problem still exists, test another vehicle to find tires that do
not exhibit the same frequency and swap those tires
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00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3886
onto the subject vehicle.
- After match mounting, the tire/wheel assembly must be rebalanced.
If match mounting tires to in-spec wheels produces assembly values higher than these, tire
replacement may be necessary. Replacing tires at lower values will probably mean good tires are
being condemned. Because tires can sometimes become temporarily flat-spotted, which will affect
force variation, it is important that the vehicle be driven at least 16 km (10 mi) prior to measuring.
Tire pressure must also be adjusted to the usage pressure on the vehicle's tire placard prior to
measuring.
Most GM vehicles will tolerate radial force variation up to these levels. However, some vehicles are
more sensitive, and may require lower levels. Also, there are other tire parameters that equipment
such as the Hunter GSP9700 cannot measure that may be a factor. In such cases, TAC should be
contacted for further instructions.
Important
- When mounting a GM wheel to a wheel balancer/force variation machine, always use the wheel's
center pilot hole. This is the primary centering mechanism on all GM wheels; the bolt holes are
secondary. Usually a back cone method to the machine should be used. For added accuracy and
repeatability, a flange plate should be used to clamp the wheel onto the cone and machine. This
system is offered by all balancer manufacturers in GM's dealer program.
- Any type of service equipment that removes tread rubber by grinding, buffing or truing is NOT
recommended, and may void the tire warranty. However, tires may have been ground by the tire
company as part of their tire manufacturing process. This is a legitimate procedure.
Steering Wheel Shake Worksheet
When diagnosing vibration concerns, use the following worksheet in conjunction with the
appropriate Vibration Analysis-Road testing procedure in the Vibration Correction sub-section in SI.
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00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3887
Refer to the appropriate section of SI for specifications and repair procedures that are related to the
vibration concern.
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels
Wheels: All Technical Service Bulletins Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels
TECHNICAL
Bulletin No.: 05-03-10-003F
Date: April 27, 2010
Subject: Low Tire Pressure, Leaking Cast Aluminum Wheels (Repair with Adhesive Sealant)
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks (Including Saturn) 2010 and Prior
HUMMER H2, H3 2009 and Prior Saab 9-7X with Cast Aluminum Wheels
Supercede: This bulletin is being revised to update the model years and the bulletin reference
information. Please discard Corporate Bulletin Number 05-03-10-003E (Section 03 - Suspension).
Condition
Some customers may comment on a low tire pressure condition.
Diagnosis of the low tire pressure condition indicates an air leak through the cast aluminum wheel.
Cause
Porosity in the cast aluminum wheel may be the cause.
Notice
This bulletin specifically addresses issues related to the wheel casting that may result in an air
leak. For issues related to corrosion of the wheel in service, please refer to Corporate Bulletin
Number 08-03-10-006C - Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light
Illuminated, Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat).
Correction
1. Remove the tire and wheel assembly from the vehicle. Refer to the appropriate service
procedure in SI. 2. Locate the leaking area by inflating the tire to 276 kPa (40 psi) and dipping the
tire/wheel assembly in a water bath, or use a spray bottle with soap
and water to locate the specific leak location.
Important
- If the porosity leak is located in the bead area of the aluminum rim (where the tire meets the rim),
the wheel should be replaced.
- If two or more leaks are located on one wheel, the wheel should be replaced.
3. If air bubbles are observed, mark the location.
- If the leak location is on the tire/rubber area, refer to Corporate Bulletin Number 04-03-10-001F Tire Puncture Repair Procedures for All Cars and Light Duty Trucks.
- If the leak is located on the aluminum wheel area, continue with the next step.
4. Inscribe a mark on the tire at the valve stem in order to indicate the orientation of the tire to the
wheel. 5. Dismount the tire from the wheel. Refer to Tire Mounting and Dismounting. 6. Remove
the tire pressure sensor. Refer to Tire Pressure Sensor removal procedure in SI. 7. Scuff the
INSIDE rim surface at the leak area with #80 grit paper and clean the area with general purpose
cleaner, such as 3M(R) General Purpose
Adhesive Cleaner, P/N 08984, or equivalent.
8. Apply a 3 mm (0.12 in) thick layer of Silicone - Adhesive/Sealant, P/N 12378478 (in Canada, use
88900041), or equivalent, to the leak area. 9. Allow for the adhesive/sealant to dry.
Notice Caution must be used when mounting the tire so as not to damage the sealer. Damaging
the repair area may result in an air leak.
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05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels > Page 3892
10. Align the inscribed mark on the tire with the valve stem on the wheel. 11. Reinstall the Tire
Pressure Sensor. Refer to Tire Pressure Sensor installation procedure in SI. 12. Mount the tire on
the wheel. Refer to Tire Mounting and Dismounting. 13. Pressurize the tire to 276 kPa (40 psi) and
inspect for leaks. 14. Adjust tire pressure to meet the placard specification. 15. Balance the
tire/wheel assembly. Refer to Tire and Wheel Assembly Balancing - Off-Vehicle. 16. Install the tire
and wheel assembly onto the vehicle. Refer to the appropriate service procedure in SI.
Parts Information
Warranty Information (excluding Saab U.S. Models)
Important The Silicone - Adhesive/Sealant comes in a case quantity of six. ONLY charge warranty
one tube of adhesive/sealant per wheel repair.
For vehicles repaired under warranty, use:
One leak repair per wheel.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON
Wheels: All Technical Service Bulletins Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON
TECHNICAL
Bulletin No.: 08-03-10-006C
Date: April 27, 2010
Subject: Tire Slowly Goes Flat, Tire Air Loss, Low Tire Pressure Warning Light Illuminated,
Aluminum Wheel Bead Seat Corrosion (Clean and Resurface Wheel Bead Seat)
Models:
2000-2011 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009 HUMMER H2
2006-2010 HUMMER H3 2005-2009 Saab 9-7X
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 08-03-10-006B (Section 03 - Suspension).
Condition
Some customers may comment on a tire that slowly loses air pressure over a period of days or
weeks.
Cause
Abrasive elements in the environment may intrude between the tire and wheel at the bead seat.
There is always some relative motion between the tire and wheel (when the vehicle is driven) and
this motion may cause the abrasive particles to wear the wheel and tire materials. As the wear
continues, there may also be intrusion at the tire/wheel interface by corrosive media from the
environment. Eventually a path for air develops and a 'slow' leak may ensue. This corrosion may
appear on the inboard or outboard bead seating surface of the wheel. This corrosion will not be
visible until the tire is dismounted from the wheel.
Notice
This bulletin specifically addresses issues related to wheel bead seat corrosion that may result in
an air leak. For issues related to porosity of the wheel casting that may result in an air leak, please
refer to Corporate Bulletin Number 05-03-10-006F - Low Tire Pressure, Leaking Cast Aluminum
Wheels (Repair with Adhesive Sealant)
Correction
In most cases, this type of air loss can be corrected by following the procedure below.
Important DO NOT replace a wheel for slow air loss unless you have evaluated and/or tried to
repair the wheel with the procedure below.
Notice
The repair is no longer advised or applicable for chromed aluminum wheels.
1. Remove the wheel and tire assembly for diagnosis. Refer to Tire and Wheel Removal and
Installation in SI. 2. After a water dunk tank leak test, if you determine the source of the air leak to
be around the bead seat of the wheel, dismount the tire to examine
the bead seat. Shown below is a typical area of bead seat corrosion.Typical Location of Bead Seat
Corrosion
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08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3897
Important Other forms of slow air leaks are possible. If the body of the tire, valve stem and wheel
flange show no signs of air seepage, refer to Corporate Bulletin Number 05-03-10-003D for
additional information on possible wheel porosity issues.
3. Bead seat corrosion is identified by what appears like blistering of the wheel finish, causing a
rough or uneven surface that is difficult for the tire to
maintain a proper seal on. Below is a close-up photo of bead seat corrosion on an aluminum wheel
that was sufficient to cause slow air loss. Close-Up of Bead Seat Corrosion
4. If corrosion is found on the wheel bead seat, measure the affected area as shown below.
- For vehicles with 32,186 km (20,000 mi) or less, the total allowable combined linear area of
repairable corrosion is 100 mm (4 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
- For vehicles that have exceeded 32,186 km (20,000 mi), the total allowable combined linear area
of repairable corrosion is 200 mm (8 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
5. In order to correct the wheel leak, use a clean-up (fine cut) sanding disc or biscuit to remove the
corrosion and any flaking paint. You should
remove the corrosion back far enough until you reach material that is stable and firmly bonded to
the wheel. Try to taper the edge of any flaking paint as best you can in order to avoid sharp edges
that may increase the chance of a leak reoccurring. The photo below shows an acceptable repaired
surface.
Notice Corrosion that extends up the lip of the wheel, where after the clean-up process it would be
visible with the tire mounted, is only acceptable on the inboard flange. The inboard flange is not
visible with the wheel assembly in the mounted position. If any loose coatings or corrosion extend
to the visible surfaces on the FACE of the wheel, that wheel must be replaced.
Important Remove ONLY the material required to eliminate the corrosion from the bead seating
surface. DO NOT remove excessive amounts of material. ALWAYS keep the sealing surface as
smooth and level as possible.
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08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3898
Acceptably Prepared (Cleaned-Up) Wheel Surface
6. Once the corrosion has been eliminated, you should coat the repaired area with a commercially
available tire sealant such as Patch Brand Bead
Sealant or equivalent. Commercially available bead sealants are black rubber-like coatings that will
permanently fill and seal the resurfaced bead seat. At 21°C (70°F) ambient temperature, this
sealant will set-up sufficiently for tire mounting in about 10 minutes.Coated and Sealed Bead Seat
7. Remount the tire and install the repaired wheel and tire assembly. Refer to Tire and Wheel
Removal and Installation in SI.
Parts Information
Patch Brand Bead Sealer is available from Myers Tires at 1-800-998-9897 or on the web at
www.myerstiresupply.com. The one-quart size can of sealer will repair about 20 wheels.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
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08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3899
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
04-03-10-012B > Feb > 08 > Wheels - Chrome Wheel Brake Dust Accumulation/Pitting
Wheels: All Technical Service Bulletins Wheels - Chrome Wheel Brake Dust Accumulation/Pitting
Bulletin No.: 04-03-10-012B
Date: February 01, 2008
INFORMATION
Subject: Pitting and Brake Dust on Chrome wheels
Models: 2008 and Prior GM Passenger Cars and Trucks (including Saturn) 2008 and Prior
HUMMER H2, H3 2005-2008 Saab 9-7X
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
04-03-10-012A (Section 03 - Suspension).
Analysis of Returned Wheels
Chrome wheels returned under the New Vehicle Limited Warranty for pitting concerns have
recently been evaluated. This condition is usually most severe in the vent (or window) area of the
front wheels. This "pitting" may actually be brake dust that has been allowed to accumulate on the
wheel. The longer this accumulation builds up, the more difficult it is to remove.
Cleaning the Wheels
In all cases, the returned wheels could be cleaned to their original condition using GM Vehicle Care
Cleaner Wax, P/N 12377966 (in Canada, P/N 10952905). When using this product, you should
confine your treatment to the areas of the wheel that show evidence of the brake dust build-up.
This product is only for use on chromed steel or chromed aluminum wheels.
Parts Information
Warranty Information
Wheel replacement for this condition is NOT applicable under the terms of the New Vehicle Limited
Warranty.
Disclaimer
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03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire Leak/Vibration
Wheels: All Technical Service Bulletins Wheels/Tires - Slow Tire Leak/Vibration
Bulletin No.: 03-03-10-001D
Date: January 17, 2008
TECHNICAL
Subject: Tire Slowly Goes Flat and/or Excessive wheel Vibration Caused By Bead Splits (Replace
wheels with New Heavy Duty Rim Version)
Models: 1999-2006 Chevrolet Silverado 1500 Series Pickup Models (Classic) 1999-2006 Chevrolet
Express 1500 Series Vans 2000-2006 Chevrolet Suburban Tahoe 1999-2006 GMC Sierra 1500
Series Pickup Models (Classic) 1999-2006 GMC Savana 1500 Series Vans 2002-2006 GMC
Yukon Yukon XL 2007 GMC Sierra Denali Crew Cab
with 6-Bolt, 16 X 6.5 Full Face Steel wheel (Base and RPO PY2)
Supercede:
This bulletin is being revised to add the Express and Savana models and add information to the
Correction section. Please discard Corporate Bulletin Number 03-03-10-001C (Section 03 Suspension).
Implementation of this service bulletin by "GM of Canada" dealers requires prior District Service
Manager approval.
Condition
Some customers may comment on a tire that slowly goes flat and/or excessive wheel vibration.
This condition is more apparent on vehicles in which customer usage typically involves frequent
severe conditions such as:
High load (at or above gross vehicle weight)
Rough road/off road usage
Fleet/Commercial usage
Cause
The wheel may experience a crack or split in the outboard bead seat weld area. A weld attaches
the rim and disc together on full-face wheels in this area. To identify this wheel it is offered in a
silver painted version P/N 9593915 code "TZA" and a chrome-clad version, P/N 9593150 code
"RSC" (these codes are stamped into the wheel's disc near the bolt holes).
Correction
Wheel replacement should only be done for air loss and/or vibration caused by bead splits.
A new heavy-duty rim version of these wheels has been released for service. The new heavy-duty
painted wheel is P/N 9595245 code "FFU" used as a road wheel and spare. The new heavy-duty
chrome clad version is P/N 9595306 code "FFW" used as a road wheel only (these codes are
stamped into the inboard rim flange balance weight area and are also on a sticker near the bolt
holes). If a condition of a crack or split as described above occurs all (5) five of the original wheels
on the vehicle should be replaced with the new heavy-duty wheels as follows: Replace road wheel
P/N 9593915 with P/N 9595245. Replace road wheel PIN 9593150 with P/N 9595306. Replace the
spare wheel with P/N 9595245 on all vehicles.
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03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire Leak/Vibration > Page 3908
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Disclaimer
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Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3914
Do not use cleaning solutions that contain hydrofluoric, oxalic and most other acids on chrome
wheels (or any wheels).
If the customer is unsure of the chemical make-up of a particular wheel cleaner, it should be
avoided.
For wheels showing signs of milky staining from acidic cleaners, refer to Customer Assistance and
Instructions below.
Warranty of Stained Chrome Wheels
Stained wheels are not warrantable. Most acid based cleaners will permanently stain chrome
wheels. Follow-up with dealers has confirmed that such cleaners were used on wheels that were
returned to the Warranty Parts Center (WPC). Any stained wheels received by the WPC will be
charged back to the dealership. To assist the customer, refer to Customer Assistance and
Instructions below.
Pitting or Spotted Appearance of Chrome Wheels Figure 2
A second type or staining or finish disturbance may result from road chemicals, such as calcium
chloride used for dust control of unpaved roads. The staining will look like small pitting (refer to
Figure 2). This staining will usually be on the leading edges of each wheel spoke, but may be
uniformly distributed. If a vehicle must be operated under such conditions, the chrome wheels
should be washed with mild soap and water and thoroughly rinsed as soon as conveniently
possible.
Important Road chemicals, such as calcium chloride used for dust control of unpaved roads, can
also stain chrome wheels. The staining will look like small pitting. This staining will usually be on
the leading edges of each wheel spoke. This is explained by the vehicle traveling in the forward
direction while being splashed by the road chemical. If a vehicle must be operated under such
conditions, the chrome wheels should be washed with mild soap and water and thoroughly rinsed
as soon as conveniently possible.
Warranty of Pitted or Spotted Chrome Wheels
Wheels returned with pitting or spotting as a result of road chemicals may be replaced one time.
Damage resulting from contact with these applied road chemicals is corrosive to the wheels finish
and may cause damage if the wheels are not kept clean.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean if they are operating the vehicle in an area that
applies calcium chloride or other dust controlling chemicals! "GM of Canada" dealers require prior
approval by the District Manager - Customer Care and Service Process (DM-CCSP).
"Stardust" Corrosion of Chrome Wheels Figure 3
A third type of finish disturbance results from prolonged exposure to brake dust and resultant
penetration of brake dust through the chrome. As brakes are applied hot particles of brake material
are thrown off and tend to be forced through the leading edge of the wheel spoke windows by
airflow. These
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3915
hot particles embed themselves in the chrome layer and create a small pit. If the material is allowed
to sit on the wheel while it is exposed to moisture or salt, it will corrode the wheel beneath the
chrome leaving a pit or small blister in the chrome.
Heavy brake dust build-up should be removed from wheels by using GM Chrome Cleaner and
Polish, P/N 1050173 (in Canada use 10953013). For moderate cleaning, light brake dust build-up
or water spots use GM Swirl Remover Polish, P/N 12377965 (in Canada, use Meguiars
Plast-X(TM) Clear Plastic Cleaner and Polish #G12310C**). After cleaning, the wheel should be
waxed using GM Cleaner Wax, P/N 12377966 (in Canada, use Meguiars Cleaner Wax
#M0616C**), which will help protect the wheel from brake dust and reduce adhesion of any brake
dust that gets on the wheel surface. For general maintenance cleaning, PEEK Metal Polish† may
be used. It will clean and shine the chrome and leave behind a wax coating that may help protect
the finish.
Warranty of Stardust Corroded Chrome Wheels
Wheels returned with pitting or spotting as a result of neglect and brake dust build-up may be
replaced one time.
Important Notify the customer that this is a one time replacement. Please stress to the customer
the vital importance of keeping the wheels clean and free of prolonged exposure to brake dust
build-up. "GM of Canada" dealers require prior approval by the District Manager - Customer Care
and Service Process (DM-CCSP).
Customer Assistance and Instructions
GM has looked for ways customers may improve the appearance of wheels damaged by acidic
cleaners. The following product and procedure has been found to dramatically improve the
appearance of stained wheels. For wheels that have milky stains caused by acidic cleaners try the
following:
Notice
THE 3M CHROME AND METAL POLISH REQUIRED FOR THIS PROCEDURE IS AN
EXTREMELY AGGRESSIVE POLISH/CLEANER. THE WHEELS MUST BE CLEANED BEFORE
APPLICATION TO AVOID SCRATCHING THE WHEEL SURFACE. THIS PRODUCT WILL
REDUCE THE THICKNESS OF THE CHROME PLATING ON THE WHEEL AND IF USED
INCORRECTLY OR EXCESSIVELY MAY REMOVE THE CHROME PLATING ALL TOGETHER,
EXPOSING A LESS BRIGHT AND BRASSY COLORED SUB-LAYER. FOLLOW INSTRUCTIONS
EXACTLY.
1. Wash the wheels with vigorously with soap and water. This step will clean and may reduce
wheel staining. Flood all areas of the wheel with water
to rinse.
2. Dry the wheels completely.
Notice Begin with a small section of the wheel and with light pressure buff off polish and examine
results. ONLY apply and rub with sufficient force and time to remove enough staining that you are
satisfied with the results. Some wheels may be stained to the extent that you may only achieve a
50% improvement while others may be able to be restored to the original lustre. IN ALL CASES,
only apply until the results are satisfactory.
3. Apply 3M Chrome and Metal Polish #39527* with a clean terry cloth towel. As you apply the
polish, the staining will be diminished. 4. When dry, buff off the polish with a clean portion of the
towel. 5. Repeat application of the 3M Chrome and Metal Polish until satisfied with the results. If
continued applications fail to improve the appearance
further discontinue use.
This procedure will improve the appearance of the wheels and may, with repeated applications,
restore the finish dramatically. For wheels that exhibit spotting from road chemicals the above
procedure may marginally improve the condition but will not restore the finish or remove the pitting.
In this type of staining the wheel finish has actually been removed in spots and no manner of
cleaning will restore the finish.
†*We believe this source and their products to be reliable. There may be additional manufacturers
of such products/materials. General Motors does not endorse, indicate any preference for or
assume any responsibility for the products or material from this firm or for any such items that may
be available from other sources.
Parts Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-002F > Apr > 11 > Wheels - Chrome Wheel Staining/Pitting/Corrosion > Page 3916
*This product is currently available from 3M. To obtain information for your local retail location
please call 3M at 1-888-364-3577.
**This product is currently available from Meguiars (Canada). To obtain information for your local
retail location please call Meguiars at 1-800-347-5700 or at www.meguiarscanada.com.
^ This product is currently available from Tri-Peek International. To obtain information for your local
retail location please call Tri-Peek at
1-877-615-4272 or at www.tripeek.com.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
99-08-51-007E > Mar > 11 > Wheels/Tires - Refinishing Aluminum Wheels > Page 3921
longer.
Important Whenever a wheel is refinished, the mounting surface and the wheel nut contact
surfaces must not be painted or clearcoated. Coating these surfaces could affect the wheel nut
torque.
When re-mounting a tire on an aluminum wheel, coated balance weights must be used in order to
reduce the chance of future cosmetic damage.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
06-03-10-010A > Jun > 10 > Wheels - Changing Procedures/Precautions > Page 3926
Some customers may use penetrating oils, grease or other lubricants on wheel studs to aid in
removal or installation. Always use a suitable cleaner/solvent to remove these lubricants prior to
installing the wheel and tire assemblies. Lubricants left on the wheel studs may cause improper
readings of wheel nut torque. Always install wheels to clean, dry wheel studs ONLY.
Notice
Lubricants left on the wheel studs or vertical mounting surfaces between the wheel and the rotor or
drum may cause the wheel to work itself loose after the vehicle is driven. Always install wheels to
clean, dry wheel studs and surfaces ONLY. Beginning with 2011 model year vehicles, put a light
coating of grease, GM P/N 1051344 (in Canada, P/N 9930370), on the inner surface of the wheel
pilot hole to prevent wheel seizure to the axle or bearing hub.
Wheel Stud and Lug Nut Damage
Always inspect the wheel studs and lug nuts for signs of damage from crossthreading or abuse.
You should never have to force wheel nuts down the stud. Lug nuts that are damaged may not
retain properly, yet give the impression of fully tightening. Always inspect and replace any
component suspected of damage.
Tip
Always start wheel nuts by hand! Be certain that all wheel nut threads have been engaged
BEFORE tightening the nut.
Important If the vehicle has directional tread tires, verify the directional arrow on the outboard side
of the tire is pointing in the direction of forward rotation.
Wheel Nut Tightening and Torque
Improper wheel nut tightening can lead to brake pulsation and rotor damage. In order to avoid
additional brake repairs, evenly tighten the wheel nuts to the proper torque specification as shown
for each vehicle in SI. Always observe the proper wheel nut tightening sequence as shown below in
order to avoid trapping the wheel on the wheel stud threads or clamping the wheel slightly off
center resulting in vibration.
The Most Important Service You Provide
While the above information is well known, and wheel removal so common, technicians run the risk
of becoming complacent on this very important
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
06-03-10-010A > Jun > 10 > Wheels - Changing Procedures/Precautions > Page 3927
service operation. A simple distraction or time constraint that rushes the job may result in personal
injury if the greatest of care is not exercised. Make it a habit to double check your work and to
always side with caution when installing wheels.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3932
of vibration is normally felt more in the "seat of the pants" than the steering wheel.
5. Next, record the Hertz (Hz) reading as displayed by the EVA onto the tire data worksheet found
at the end of this bulletin. This should be done
after a tire break-in period of at least 16 km (10 mi) at 72 km/h (45 mph) or greater, in order to
eliminate any possible tire flat-spotting. This reading confirms what the vehicle vibration frequency
is prior to vehicle service and documents the amount of improvement occurring as the result of the
various steps taken to repair. Completing the Steering Wheel Shake Worksheet below is required.
A copy of the completed worksheet must be saved with the R.O. and a copy included with any
parts returned to the Warranty Parts Center for analysis. A reading of 35 to 50 Hz typically
indicates a first order propshaft vibration. If this is the situation, refer to Corporate Bulletin Number
08-07-30-044D. Generally, a reading between 10 and 20 Hz indicates a tire/wheel vibration and if
this is the reading obtained, continue using this bulletin. If the tire 1st order vibration goes away
and stays away during this evaluation, the cause is likely tire flat-spotting. Tire flat-spotting vibration
may come and go at any speed over 72 km/h (45 mph) during the first 10 minutes of operation, if
vibration continues after 10 minutes of driving at speeds greater than 72 km/h (45 mph), tire
flat-spotting can be ruled out as the cause for vibration.
6. If flat-spotting is the cause, provide the explanation that this has occurred due to the vehicle
being parked for long periods of time and that the
nature of the tire is to take a set. Refer to Corporate Bulletin Number 03-03-10-007E: Information
on Tire/Wheel Characteristics (Vibration, Balance, Shake, Flat Spotting) of GM Original Equipment
Tires.
7. If the road test indicates a shake/vibration exists, check the imbalance of each tire/wheel
assembly on a known, calibrated, off-car dynamic
balancer.Make sure the mounting surface of the wheel and the surface of the balancer are
absolutely clean and free of debris. Be sure to chose the proper cone/collet for the wheel, and
always use the pilot bore for centering. Never center the wheel using the hub-cap bore since it is
not a precision machined surface. If any assembly calls for more than 1/4 ounce on either rim
flange, remove all balance weights and rebalance to as close to zero as possible. If you can see
the vibration (along with feeling it) in the steering wheel (driving straight without your hands on the
wheel), it is very likely to be a tire/wheel first order (one pulse per revolution) disturbance. First
order disturbances can be caused by imbalance as well as non-uniformities in tires, wheels or
hubs. This first order frequency is too low for a human to hear, but if the amplitude is high enough,
it can be seen.
If a vibration or shake still exists after balancing, any out of round conditions, of the wheel, and
force variation conditions of the tire, must be addressed. Equipment such as the Hunter GSP9700
can address both (it is also a wheel balancer).
Tire radial force vibration (RFV) can be defined as the amount of stiffness variation the tire will
produce in one revolution under a constant load. Radial force variation is what the vehicle feels
because the load (weight) of the vehicle is always on the tires. Although free runout of tires (not
under load) is not always a good indicator of a smooth ride, it is critical that total tire/wheel
assembly runout be within specification.
Equipment such as the Hunter GSP9700 loads the tire, similar to on the vehicle, and measures
radial force variation of the tire/wheel assembly. Note that the wheel is affecting the tire's RFV
measurement at this point. To isolate the wheel, its runout must be measured. This can be easily
done on the Hunter, without the need to set up dial indicators. If the wheel meets the runout
specification, the tire's RFV can then be addressed.
After measuring the tire/wheel assembly under load, and the wheel alone, the machine then
calculates (predicts) the radial force variation of the tire. However, because this is a prediction that
can include mounting inaccuracies, and the load wheel is much smaller in diameter than used in
tire production, this type of service equipment should NOT be used to audit new tires. Rather, it
should be used as a service diagnostic tool to minimize radial force variation of the tire/wheel
assembly.
Equipment such as the Hunter GSP9700 does an excellent job of measuring wheel runout, and of
finding the low point of the wheel (for runout) and the high point of the tire (for radial force
variation). This allows the tire to be matched mounted to the wheel for lowest tire/wheel assembly
force variation.
The machine will simplify this process into easy steps. The following assembly radial force variation
numbers should be used as a guide:
When measuring RFV and match mounting tires perform the following steps.
Measuring Wheel Runout and Assembly Radial Force Variation
Important The completed worksheet at the end of this bulletin must be attached to the hard copy of
the repair order.
- Measure radial force variation and radial runout.
- If a road force/balancing machine is used, record the radial force variation (RFV) on the
worksheet at the end of this bulletin. It may be of benefit to have the lowest RFV assembly to the
front left corner. If the machine is not available and the EVA data suggests there is an issue, swap
the tire and wheel assemblies from the front to the back. Re-check on the EVA and if the problem
still exists, test another vehicle to find tires that do not exhibit the same frequency and swap those
tires onto the subject vehicle.
- If a runout/balancing machine is used, record the radial runout of the tire/wheel assemblies on the
worksheet at the end of this bulletin. If one or more of the tire/wheel assemblies are more than.040
in (1.02 mm), match mount the tire to the wheel to get below.040 in (1.02 mm). For sensitive
customers, readings of 0.030 inch (0.76 mm) or less are preferable, it may also be of benefit to
have the lowest runout assembly to the front left corner. If the machine is not available and the
EVA data suggests there is an issue, swap the tire and wheel assemblies from the front to the
back. Re-check on the EVA and if the problem still exists, test another vehicle to find tires that do
not exhibit the same frequency and swap those tires
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3933
onto the subject vehicle.
- After match mounting, the tire/wheel assembly must be rebalanced.
If match mounting tires to in-spec wheels produces assembly values higher than these, tire
replacement may be necessary. Replacing tires at lower values will probably mean good tires are
being condemned. Because tires can sometimes become temporarily flat-spotted, which will affect
force variation, it is important that the vehicle be driven at least 16 km (10 mi) prior to measuring.
Tire pressure must also be adjusted to the usage pressure on the vehicle's tire placard prior to
measuring.
Most GM vehicles will tolerate radial force variation up to these levels. However, some vehicles are
more sensitive, and may require lower levels. Also, there are other tire parameters that equipment
such as the Hunter GSP9700 cannot measure that may be a factor. In such cases, TAC should be
contacted for further instructions.
Important
- When mounting a GM wheel to a wheel balancer/force variation machine, always use the wheel's
center pilot hole. This is the primary centering mechanism on all GM wheels; the bolt holes are
secondary. Usually a back cone method to the machine should be used. For added accuracy and
repeatability, a flange plate should be used to clamp the wheel onto the cone and machine. This
system is offered by all balancer manufacturers in GM's dealer program.
- Any type of service equipment that removes tread rubber by grinding, buffing or truing is NOT
recommended, and may void the tire warranty. However, tires may have been ground by the tire
company as part of their tire manufacturing process. This is a legitimate procedure.
Steering Wheel Shake Worksheet
When diagnosing vibration concerns, use the following worksheet in conjunction with the
appropriate Vibration Analysis-Road testing procedure in the Vibration Correction sub-section in SI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
00-03-10-006F > May > 10 > Wheels/Tires - Tire Radial Force Variation (RFV) > Page 3934
Refer to the appropriate section of SI for specifications and repair procedures that are related to the
vibration concern.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
05-03-10-003F > Apr > 10 > Tires/Wheels - Low Tire/Leaking Cast Aluminum Wheels > Page 3939
10. Align the inscribed mark on the tire with the valve stem on the wheel. 11. Reinstall the Tire
Pressure Sensor. Refer to Tire Pressure Sensor installation procedure in SI. 12. Mount the tire on
the wheel. Refer to Tire Mounting and Dismounting. 13. Pressurize the tire to 276 kPa (40 psi) and
inspect for leaks. 14. Adjust tire pressure to meet the placard specification. 15. Balance the
tire/wheel assembly. Refer to Tire and Wheel Assembly Balancing - Off-Vehicle. 16. Install the tire
and wheel assembly onto the vehicle. Refer to the appropriate service procedure in SI.
Parts Information
Warranty Information (excluding Saab U.S. Models)
Important The Silicone - Adhesive/Sealant comes in a case quantity of six. ONLY charge warranty
one tube of adhesive/sealant per wheel repair.
For vehicles repaired under warranty, use:
One leak repair per wheel.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3944
Important Other forms of slow air leaks are possible. If the body of the tire, valve stem and wheel
flange show no signs of air seepage, refer to Corporate Bulletin Number 05-03-10-003D for
additional information on possible wheel porosity issues.
3. Bead seat corrosion is identified by what appears like blistering of the wheel finish, causing a
rough or uneven surface that is difficult for the tire to
maintain a proper seal on. Below is a close-up photo of bead seat corrosion on an aluminum wheel
that was sufficient to cause slow air loss. Close-Up of Bead Seat Corrosion
4. If corrosion is found on the wheel bead seat, measure the affected area as shown below.
- For vehicles with 32,186 km (20,000 mi) or less, the total allowable combined linear area of
repairable corrosion is 100 mm (4 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
- For vehicles that have exceeded 32,186 km (20,000 mi), the total allowable combined linear area
of repairable corrosion is 200 mm (8 in) or less. If the total area(s) of corrosion exceed these
dimensions, the wheel should be replaced.
5. In order to correct the wheel leak, use a clean-up (fine cut) sanding disc or biscuit to remove the
corrosion and any flaking paint. You should
remove the corrosion back far enough until you reach material that is stable and firmly bonded to
the wheel. Try to taper the edge of any flaking paint as best you can in order to avoid sharp edges
that may increase the chance of a leak reoccurring. The photo below shows an acceptable repaired
surface.
Notice Corrosion that extends up the lip of the wheel, where after the clean-up process it would be
visible with the tire mounted, is only acceptable on the inboard flange. The inboard flange is not
visible with the wheel assembly in the mounted position. If any loose coatings or corrosion extend
to the visible surfaces on the FACE of the wheel, that wheel must be replaced.
Important Remove ONLY the material required to eliminate the corrosion from the bead seating
surface. DO NOT remove excessive amounts of material. ALWAYS keep the sealing surface as
smooth and level as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3945
Acceptably Prepared (Cleaned-Up) Wheel Surface
6. Once the corrosion has been eliminated, you should coat the repaired area with a commercially
available tire sealant such as Patch Brand Bead
Sealant or equivalent. Commercially available bead sealants are black rubber-like coatings that will
permanently fill and seal the resurfaced bead seat. At 21°C (70°F) ambient temperature, this
sealant will set-up sufficiently for tire mounting in about 10 minutes.Coated and Sealed Bead Seat
7. Remount the tire and install the repaired wheel and tire assembly. Refer to Tire and Wheel
Removal and Installation in SI.
Parts Information
Patch Brand Bead Sealer is available from Myers Tires at 1-800-998-9897 or on the web at
www.myerstiresupply.com. The one-quart size can of sealer will repair about 20 wheels.
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table above.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
08-03-10-006C > Apr > 10 > Tires/Wheels - Tire Slowly Goes Flat/Warning Light ON > Page 3946
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Intake Manifold
Gasket > Component Information > Technical Service Bulletins > All Other Service Bulletins for Intake Manifold Gasket: >
03-03-10-001D > Jan > 08 > Wheels/Tires - Slow Tire Leak/Vibration > Page 3955
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications
Valve Guide Seal: Specifications
Valve System
Valve Stem Clearance (Production-Exhaust)
.............................................................................................................. 0.025-0.066 mm
(0.001-0.0026 inch) Valve Stem Clearance (Production-Intake)
................................................................................................................. 0.025-0.066 mm
(0.001-0.0026 inch) Valve Stem Clearance (Service-Exhaust)
................................................................................................ 0.093 mm (Maximum) (0.0037 inch
(Maximum)) Valve Stem Clearance (Service-Intake)
................................................................................................... 0.093 mm (Maximum) (0.0037 inch
(Maximum)) Valve Stem Diameter (Production)
............................................................................................................................. 7.955-7.976 mm
(0.3132-0 314 inch) Valve Stem Diameter (Service)
..................................................................................................................... 7.95 mm (Minimum)
(0.313 inch (Minimum)) Valve Stem Oil Seal Installed Height (Measured from the Valve Spring
Shim to Top Edge of Seal Body - First Design Seal) ..................... 18.1-19.1 mm
(0.712-0.752 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications > Page 3959
Valve Guide Seal: Service and Repair
Valve Stem Oil Seal and Valve Spring Replacement
- Tools Required -
J 22794 Spark Plug Port Adapter
- J 38606 Valve Spring Compressor
- J 42078 Valve Stem Oil Seal Installer
Removal Procedure
1. Remove the valve rocker arm. 2. Disconnect the spark plug wire at the spark plug.
- Twist each plug wire boot 1/2 turn.
- Pull only on the boot in order to remove the wire from the spark plug.
Important: Remove the spark plugs from the cylinder head with the engine at room temperature.
3. Loosen the spark plug 1 or 2 turns. 4. Brush or air blast away any dirt or debris from around the
spark plug. 5. Remove the spark plug.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications > Page 3960
6. Install J 22794 into the spark plug hole. 7. Attach an air hose to J22794. 8. Apply compressed air
to J 22794 in order to hold the valves in place.
9. Use J 38606 in order to compress the valve spring.
10. Remove the valve stem keys (3). 11. Carefully release the valve spring tension.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications > Page 3961
12. Remove the J 38606. 13. Remove the valve spring cap (4). 14. Remove the valve spring (5).
Important: A second design valve stem oil seal and shim may be used on later engines. A separate
spring shim is not required with the second design seal and shim.
15. Remove the valve stem oil seal (6) (first design). 16. Remove the valve spring shim (7) (first
design). 17. Remove the valve stem oil seal and shim (2) (second design)
Installation Procedure
1. Clean the cylinder head valve spring seat and/or shim area. 2. Install the valve spring shim (7)
(first design). 3. Install the valve stem oil seal and shim (2) (second design). J42078 is not required
for installation of the second design seal and shim.
Important: The valve stem oil seal alignment and position on the valve guide is critical.
An improperly installed valve stem oil seal may lead to excessive oil consumption, increased
vehicle emissions, or component damage.
4. Install the valve stem oil seal (first design) onto the guide.
4.1. Lubricate the valve guide and valve stem oil seal with clean engine oil.
4.2. Install the valve stem oil seal (first design) onto the valve stem. Push the seal down until the
seal contacts the valve guide.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications > Page 3962
4.3. Use the J 42078 in order to install the valve stem oil seal. Push or lightly tap the tool until the
tool bottoms against the valve spring shim.
5. Measure the valve stem oil seals (first design) for the properly installed height. There should be
a 18.1 - 19.1 mm (0.712 - 0.752 inch) gap
between the top edge of the oil seal body and the valve spring shim surface.
6. Install the valve spring (5). 7. Install the valve spring cap (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Seals and Gaskets, Engine > Valve Guide Seal >
Component Information > Specifications > Page 3963
8. Compress the valve spring using the J 38606. 9. Install the valve keys.
- Use grease in order to hold the valve keys in place.
- Make sure the keys seat properly in the groove of the valve stem.
- Carefully release the valve spring pressure, making sure the valve keys stay in place.
- Remove the J 38606.
- Tap the end of the valve stem with a plastic faced hammer to seat the keys (if necessary).
10. Remove J 22794 from the spark plug port.
Notice: Refer to Fastener Notice in Service Precautions.
11. Hand start the spark plug.
- Tighten the spark plug to 15 Nm (11 ft. lbs.).
12. Install the spark plug wires at the ignition coil. 13. Install the spark plug wire to the spark plug.
14. Inspect the wires for proper installation:
- Push sideways on each boot in order to check for proper installation.
- Reinstall any loose boot.
15. Install the valve rocker arm.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Level
Sensor > Component Information > Specifications
Oil Level Sensor: Specifications
Oil Level Sensor ..................................................................................................................................
................................................ 13 Nm (115 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Level
Sensor > Component Information > Specifications > Page 3968
Oil Level Sensor: Service and Repair
Engine Oil Level Sensor and/or Switch Replacement
Removal Procedure
1. Drain the engine oil. 2. Disconnect the oil level sensor electrical connector (6).
3. Remove the oil level sensor from the oil pan.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the oil level sensor to the oil pan.
- Tighten the oil level sensor to 13 Nm (115 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Level
Sensor > Component Information > Specifications > Page 3969
2. Connect the oil level sensor electrical connector (6). 3. Fill the engine oil.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Level
Sensor For ECM > Component Information > Diagrams
Engine Oil Level Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Pressure
Sender > Component Information > Diagrams
Engine Oil Pressure (EOP) Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Pressure
Sender > Component Information > Diagrams > Page 3976
Oil Pressure Sender: Service and Repair
Engine Oil Pressure Sensor and/or Switch Replacement
- Tools Required J 41712 Oil Pressure Sensor Socket
Removal Procedure
1. If necessary, remove the engine sight shield. 2. Disconnect the oil pressure sensor electrical
connector (1).
3. Using J 41712 or equivalent, remove the oil pressure sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Sensors and Switches - Engine > Oil Pressure
Sender > Component Information > Diagrams > Page 3977
1. Apply sealant GM U.S. P/N 12346004, Canada P/N 10953480, or equivalent, to the threads of
the oil pressure sensor.
Notice: Refer to Fastener Notice in Service Precautions.
2. Using J 41712 or equivalent, install the oil pressure sensor.
- Tighten the oil pressure sensor to 20 Nm (15 ft. lbs.).
3. Connect the oil pressure sensor electrical connector (1). 4. If necessary, install the engine sight
shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Chain > Component
Information > Service and Repair
Timing Chain: Service and Repair
Timing Chain and Sprockets Installation
- Tools Required J 41665 Crankshaft Balancer and Sprocket Installer
1. Install the key into the crankshaft keyway, if previously removed.
2. Tap the key (1) into the keyway until both ends of the key bottom onto the crankshaft.
3. Install the crankshaft sprocket onto the front of the crankshaft. Align the crankshaft key with the
crankshaft sprocket keyway.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Chain > Component
Information > Service and Repair > Page 3982
4. Use the J 41665 in order to install the crankshaft sprocket.
Install the sprocket onto the crankshaft until fully seated against the crankshaft flange.
5. Rotate the crankshaft sprocket until the alignment mark is in the 12 o'clock position.
Important: Properly locate the camshaft sprocket locating pin with the camshaft sprocket alignment hole.
- The sprocket teeth and timing chain must mesh.
- The camshaft and the crankshaft sprocket alignment marks MUST be aligned properly. Locate
the camshaft sprocket alignment mark in the 6 o'clock position.
6. Install the camshaft sprocket and timing chain.
7. If necessary, rotate the camshaft or crankshaft sprockets in order to align the timing marks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Chain > Component
Information > Service and Repair > Page 3983
Notice: Refer to Fastener Notice in Service Precautions.
8. Install the camshaft sprocket bolts.
- Tighten the camshaft sprocket bolts to 35 Nm (26 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Cover > Component
Information > Specifications
Timing Cover: Specifications
Engine Front Cover Bolt ......................................................................................................................
..................................................... 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Cover > Component
Information > Specifications > Page 3987
Timing Cover: Service and Repair
Engine Front Cover Replacement
- Tools Required J 41476 Front and Rear Cover Alignment (at crankshaft seal area)
Removal Procedure
1. Remove the water pump. 2. Remove the crankshaft balancer. 3. Remove the oil pan-to-front
cover bolts.
4. Remove the front cover bolts. 5. Remove the front cover and gasket. 6. Discard the front cover
gasket. 7. Clean and inspect the engine front cover.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Cover > Component
Information > Specifications > Page 3988
Important: Do not reuse the crankshaft oil seal or front cover gasket.
- Do not apply any type of sealant to the front cover gasket (unless specified).
- The special tool in this procedure is used to properly center the front crankshaft front oil seal. All gasket surfaces should be free of oil or other foreign material during assembly.
- The crankshaft front oil seal MUST be centered in relation to the crankshaft.
- An improperly aligned front cover may cause premature front oil seal wear and/or engine oil leaks.
1. Apply a 5 mm (0.20 inch) bead of sealant GM U.S. P/N 12378190, or equivalent 20 mm (0.80
inch) long to the oil pan to engine block junction. 2. Install the front cover gasket and cover. 3.
Install the front cover bolts until snug. Do not overtighten.
4. Install the oil pan-to-front cover bolts until snug. Do not over tighten.
5. Install J 41476 to the front cover. 6. Align the tapered legs of the J41476with the machined
alignment surfaces on the front cover.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Timing Components > Timing Cover > Component
Information > Specifications > Page 3989
7. Install the crankshaft balancer bolt until snug. Do not overtighten.
7.1. Tighten the oil pan to front cover bolts to 25 Nm (18 ft. lbs.).
7.2. Tighten the engine front cover bolts to 25 Nm (18 ft. lbs.).
8. Remove the J 41476. 9. Install a NEW crankshaft front oil seal.
10. Install the water pump.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > Specifications
Fuel Pressure: Specifications
Measure with the Key On Engine Off with the fuel pump commanded ON.
Vin (V,T,U)
Fuel Pressure (gasoline) .....................................................................................................................
................................................................. 55-62 psi
Vin (Z)
Fuel Pressure (ethanol) .......................................................................................................................
................................................................. 48-54 psi
These specifications are taken from the Fuel System Diagnosis. For complete testing of fuel
pressures and volume see Fuel System Diagnosis, See: Powertrain Management/Computers and
Control Systems/Testing and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal
Fuel Pressure: Testing and Inspection Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 3996
Fuel Pressure: Testing and Inspection Fuel System Diagnosis
SYSTEM DESCRIPTION
When you turn ON the ignition switch, the control module enables the fuel pump relay which
powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running
and the control module receives ignition reference pulses. If there are no ignition reference pulses,
the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the
ON position or if the engine stops.
The fuel tank stores the fuel supply. The electric fuel pump supplies fuel through an in-line fuel filter
to the fuel injection system. The pump provides fuel at a higher rate of flow than is needed by the
fuel injection system. The fuel pressure regulator maintains the correct fuel pressure to the fuel
injection system. A separate pipe returns unused fuel to the fuel tank.
TEST DESCRIPTION
Steps 1-2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 3997
Steps 3-7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 3998
Steps 8-13
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 3999
Steps 14-18
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Pressure > System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 4000
Steps 19-25
The numbers below refer to the step numbers on the diagnostic table. 2. This step verifies that the
fuel pump is operating. 4. This step tests for an internal fuel leak. If the fuel pressure drops during
this test, then an internal loss of pressure is indicated. 6. This step tests the fuel pressure regulator.
The fuel pressure regulator is controlled by the engine vacuum. With the engine vacuum applied,
the
pressure should drop to the specified value.
9. This step inspects the fuel pressure regulator for a fuel leak from the vacuum port. If fuel leaks
from the fuel pressure regulator while the fuel
pump is commanded ON, replace the fuel pressure regulator.
10. This step tests for a loss of fuel pressure between the fuel feed pipe shut-off adapter and the
fuel pump. 11. This step tests for a leaking fuel injector or for a leaking fuel pressure regulator. If
the fuel pressure remains constant during this test, the fuel
injectors are not leaking fuel.
14. This step tests for a restricted fuel return pipe. If the fuel pressure is within the specified values,
there is a restriction in the fuel return pipe. 16. This step determines if the fuel pressure regulator or
the fuel pump is the cause of the low fuel pressure. If the pressure rises above the specified
value, the fuel pump is OK.
18. This step verifies that a circuit condition is not the cause of a fuel pressure concern. Thoroughly
inspect all fuel electrical circuits.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Idle
Speed > System Information > Specifications
Idle Speed: Specifications
Idle Speed ...........................................................................................................................................
.............................................................. 500-700 rpm
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Cleaner Restriction Indicator > Component Information > Description and Operation
Air Cleaner Restriction Indicator: Description and Operation
Air Cleaner Restriction Indicator
The air cleaner restriction indicator is located on the air cleaner assembly between the air filter and
the mass air flow (MAF) sensor.
If the area inside of the clear section is green, no air filter service is required. If the area inside the
clear section is orange and Change Air Filter appears, replace the air filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > Customer Interest: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: Customer Interest Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > Customer Interest: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 4016
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Technical Service
Bulletins: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: All Technical Service Bulletins Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Technical Service
Bulletins: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 4022
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Other Service Bulletins
for Air Filter Element: > 05-08-50-012A > Jul > 06 > Interior - Loose/Unwanted Seat Movement
Seat Track: All Technical Service Bulletins Interior - Loose/Unwanted Seat Movement
Bulletin No.: 05-08-50-012A
Date: July 24, 2006
TECHNICAL
Subject: Unwanted/Loose Seat Movement (Apply Adhesive and Install New Bolts in Seat Mounting
Rails)
Models: 2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac ESV 1999-2007
Chevrolet Silverado Pickup Models (Classic) 2000-2006 Chevrolet Suburban, Tahoe 2002-2006
Chevrolet Avalanche 1999-2007 GMC Sierra Pickup Models (Classic) 2000-2006 GMC Yukon,
Yukon XL 2003-2006 HUMMER H2
with Power Driver Front Seat Power Adjuster (RPO AG1) and/or Passenger Seat Power Adjuster
(RPO AG2)
Supercede:
This bulletin is being revised to add model years and additional Warranty Information. Please
discard Corporate Bulletin Number 05-08-50-012 (Section 08 - Body and Accessories).
Condition
Some customers may comment on unwanted seat movement in the front power bucket seat (driver
or passenger) during fast acceleration or hard braking. A metal to metal clicking noise is often
heard at seat "stops."
Cause
The threads of the two zinc nut retainers (one on each side of the seat adjuster) may creep over
time, causing a loss of self-rolling screw clamp load and ultimately causes relative rail and vehicle
seat motion.
Correction
Apply adhesive and install new bolts in seat mounting rails using the following procedure.
1. Remove the front seat and invert onto a flat surface covered with a clean, non-scratch material
(soft cloth or similar). Refer to the applicable Seats sub-section in SI. Adjust so that the seat
mounting rails are at 45 degrees.
2. Remove the upper M8 mounting bolt from one rail and discard. Leave the other bolt intact as this
will hold the track in place while working. Wipe the bolt hole area with a clean rag.
Important:
Only use the adhesive provided in the repair kit. Do not substitute with other adhesives.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Other Service Bulletins
for Air Filter Element: > 05-08-50-012A > Jul > 06 > Interior - Loose/Unwanted Seat Movement > Page 4028
3. Take one of the adhesive sachets and carefully cut the flag tip off the notched end spout in line
with the notch.
4. While holding the sachet vertical, slowly dribble the adhesive into the edge of the bolt hole as
shown, ensuring that the adhesive flows into the joint between the seat rail and the zinc block. DO
NOT pour the adhesive down the center of the hole. The object is to let the adhesive "wick"
between the zinc block and the seat rail in order to bond the two pieces together.
Important:
If the bolt thread strips or the proper torque cannot be achieved, then the entire seat adjuster
mechanism must be replaced.
5. Replace the previous bolt with a new M8 bolt (1) (included) and install using a "click torque
wrench" preset to 9 N.m (79 lb in).
6. Remove the second M8 mounting bolt from the rail and discard.
7. Repeat steps 2 through 5 for the second bolt.
8. Repeat steps 2 through 6 for the opposite mounting rail.
9. Before installing the seat into the vehicle, verify that the seat will function correctly and does not
make any unusual noises during forward and rearward travel motion.
10. Install the seat. Refer to the applicable Seats sub-section of SI.
11. While sitting in the seat, verify seat function and listen for any unusual noises.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Other Service Bulletins
for Air Filter Element: > 05-08-50-012A > Jul > 06 > Interior - Loose/Unwanted Seat Movement > Page 4029
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Other Service Bulletins
for Air Filter Element: > 05-08-50-012A > Jul > 06 > Interior - Loose/Unwanted Seat Movement > Page 4035
3. Take one of the adhesive sachets and carefully cut the flag tip off the notched end spout in line
with the notch.
4. While holding the sachet vertical, slowly dribble the adhesive into the edge of the bolt hole as
shown, ensuring that the adhesive flows into the joint between the seat rail and the zinc block. DO
NOT pour the adhesive down the center of the hole. The object is to let the adhesive "wick"
between the zinc block and the seat rail in order to bond the two pieces together.
Important:
If the bolt thread strips or the proper torque cannot be achieved, then the entire seat adjuster
mechanism must be replaced.
5. Replace the previous bolt with a new M8 bolt (1) (included) and install using a "click torque
wrench" preset to 9 N.m (79 lb in).
6. Remove the second M8 mounting bolt from the rail and discard.
7. Repeat steps 2 through 5 for the second bolt.
8. Repeat steps 2 through 6 for the opposite mounting rail.
9. Before installing the seat into the vehicle, verify that the seat will function correctly and does not
make any unusual noises during forward and rearward travel motion.
10. Install the seat. Refer to the applicable Seats sub-section of SI.
11. While sitting in the seat, verify seat function and listen for any unusual noises.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Other Service Bulletins
for Air Filter Element: > 05-08-50-012A > Jul > 06 > Interior - Loose/Unwanted Seat Movement > Page 4036
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > Page 4037
Air Filter Element: Service and Repair
AIR CLEANER ELEMENT REPLACEMENT
REMOVAL PROCEDURE
1. Remove the intake duct (2). 2. Disconnect the electrical connector from the mass air flow/intake
air temperature (MAF/IAT) sensor.
3. Loosen the 4 fasteners (8) securing the air cleaner housing top cover (4). 4. Lift and rotate the
top cover (4) of the air cleaner housing to gain access to the air filter element. 5. Lift out the air filter
element (5). 6. Inspect the air filter element for dust, dirt, or water. Clean or replace the air filter
element if required.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Air
Cleaner Housing > Air Filter Element > Component Information > Technical Service Bulletins > Page 4038
1. Install the air filter element (5) into the air cleaner housing. 2. Rotate and install the top cover (4)
to the air cleaner housing (6). 3. Insert the fasteners (8) to secure the top cover.
4. Connect the MAF/IAT electrical connector. 5. Install the intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Filter > Fuel Pressure Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Fuel
Filter > Fuel Pressure Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
> Page 4044
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Ignition Cable > Component Information > Specifications
Ignition System Specifications
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Ignition Cable > Component Information > Service and Repair > Spark Plug Wire Inspection
Ignition Cable: Service and Repair Spark Plug Wire Inspection
Spark plug wire integrity is vital for proper engine operation. A thorough inspection will be
necessary to accurately identify conditions that may affect engine operation. Inspect for the
following conditions:
^ Correct routing of the spark plug wires-Incorrect routing may cause cross-firing.
^ Any signs of cracks or splits in the wires.
^ Inspect each boot for the following conditions: Tearing
- Piercing
- Arcing
- Carbon tracking
- Corroded terminal
If corrosion, carbon tracking or arcing are indicated on a spark plug wire boot or on a terminal,
replace the wire and the component connected to the wire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Ignition Cable > Component Information > Service and Repair > Spark Plug Wire Inspection > Page 4050
Ignition Cable: Service and Repair Spark Plug Wire Replacement
REMOVAL PROCEDURE
1. Disconnect the spark plug wire at each spark plug.
^ Twist each spark plug 1/2 turn.
^ Pull only on the boot in order to remove the wire from each spark plug.
2. Disconnect the spark plug wire from the ignition coil.
^ Twist each spark plug boot 1/2 turn.
^ Pull only on the boot in order to remove the wires from the ignition coil.
SPARK PLUG WIRE LENGTH V8
Spark Plug Wire Length V8
^ The Melco(R), square design, uses a spark plug wire (1) that is 145 mm (5.70 in) length cable
seal to cable seal.
^ The Delphi(R), round design uses a spark plug wire (2) that is 110 mm (4.30 in) length cable seal
to cable seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Ignition Cable > Component Information > Service and Repair > Spark Plug Wire Inspection > Page 4051
Ignition Coils
^ There are 2 different manufacturers for the ignition coils, the Melco(R) (1) square design, and the
Delphi(R) (2) round design. These 2 coils use 2 different spark plug wire, and mounting brackets.
^ Melco(R), square design, coil mounting bracket (1).
^ Delphi(R), round design, coil mounting bracket (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Ignition Cable > Component Information > Service and Repair > Spark Plug Wire Inspection > Page 4052
1. Install the spark plug wires at the ignition coil. 2. Install the spark plug wire to each spark plug. 3.
Inspect the wires for proper installation:
^ Push sideways on each boot in order to inspect the seating.
^ Reinstall any loose boot.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Spark
Plug > Component Information > Technical Service Bulletins > Ignition System - New Spark Plugs & Gapping Info.
Spark Plug: Technical Service Bulletins Ignition System - New Spark Plugs & Gapping Info.
INFORMATION
Bulletin No.: 03-06-04-060B
Date: July 30 2008
Subject: Information on New Spark Plugs and Gapping
Models
Attention:
Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACOelco(R)
Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
Supercede:
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard
Corporate Bulletin Number 03-06-04-060A (Section 06 - Engine/Propulsion System).
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the different tip design the gap of the spark
plug has also changed.
^ The new spark plug P/N 12571164 with AC Delco P/N 41-985 is gapped to 1.01 mm (0.040 in)
when the spark plug is made.
Notice:
The spark plug gap is set during manufacturing and should not be changed or damage to the spark
plug may result. Any new spark plug found to not be properly gapped should not be used.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Technical Service Bulletins > Page 4057
Spark Plug: Specifications
This article has been updated with TSB #03-06-04-060B
INFORMATION ON NEW SPARK PLUGS AND GAPPING
SPARK PLUG GAP..............................................................................................................................
.................................................. 1.01 mm (0.040 in.)
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the
different tip design, the gap of the spark plug has also changed.
^ The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040
inches) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to
the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Technical Service Bulletins > Page 4058
Spark Plug: Application and ID
AC Plug Type ......................................................................................................................................
................................................................... 25171803
NGK Plug Type ....................................................................................................................................
................................................................. 12567759
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Service and Repair > Spark Plug Inspection
Spark Plug: Service and Repair Spark Plug Inspection
SPARK PLUG USAGE
^ Verify that the correct spark plug is installed. An incorrect spark plug causes driveability
conditions. Refer to Ignition System Specifications for the correct spark plug.
^ Ensure that the spark plug has the correct heat range. An incorrect heat range causes the
following conditions: Spark plug fouling-Colder plug
- Pre-ignition causing spark plug and/or engine damage-Hotter plug
SPARK PLUG INSPECTION
^ Inspect the terminal P05 (1) for damage. Inspect for a bent or broken terminal post (1).
- Test for a loose terminal post (1) by twisting and pulling the post. The terminal post (1) should
NOT move.
^ Inspect the insulator (2) for flashover or carbon tracking, soot. This is caused by the electrical
charge traveling across the insulator (2) between the terminal post (1) and ground. Inspect for the
following conditions: Inspect the spark plug boot for damage.
- Inspect the spark plug recess area of the cylinder head for moisture, such as oil, coolant, or
water. A spark plug boot that is saturated causes arcing to ground.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Service and Repair > Spark Plug Inspection > Page 4061
^ Inspect the insulator (2) for cracks. All or part of the electrical charge may arc through the crack
instead of the electrodes (3, 4).
^ Inspect for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to
Ignition System Specifications. An excessively wide electrode gap can prevent correct spark plug
operation.
- Inspect for the correct spark plug torque. Refer to Ignition System Specifications. Insufficient
torque can prevent correct spark plug operation. An over torqued spark plug, causes the insulator
(2) to crack.
- Inspect for signs of tracking that occurred near the insulator tip instead of the center electrode (4).
- Inspect for a broken or worn side electrode (3).
- Inspect for a broken, worn, or loose center electrode (4) by shaking the spark plug. ^
A rattling sound indicates internal damage.
^ A loose center electrode (4) reduces the spark intensity.
- Inspect for bridged electrodes (3, 4). Deposits on the electrodes (3, 4) reduce or eliminates the
gap.
- Inspect for worn or missing platinum pads on the electrodes (3, 4), if equipped.
- Inspect for excessive fouling.
^ Inspect the spark plug recess area of the cylinder head for debris. Dirty or damaged threads can
cause the spark plug not to seat correctly during installation.
SPARK PLUG VISUAL INSPECTION
^ Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal
combustion by-products from fuels with additives.
^ Carbon fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures ^
Leaking fuel injectors
^ Excessive fuel pressure
^ Restricted air filter element
^ Incorrect combustion
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Service and Repair > Spark Plug Inspection > Page 4062
- Reduced ignition system voltage output ^
Weak coils
^ Worn ignition wires
^ Incorrect spark plug gap
- Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that
normal combustion deposits may not burn off.
^ Deposit fouling-Oil, coolant, or additives that include substances such as silicone, very white
coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless
they form into a glazing over the electrode.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Spark Plug > Component Information > Service and Repair > Spark Plug Inspection > Page 4063
Spark Plug: Service and Repair Spark Plug Replacement
REMOVAL PROCEDURE
1. Remove the spark plug wires. 2. Loosen each spark plug 1 or 2 turns. 3. Brush or air blast away
any dirt from around the spark plugs. 4. Remove the spark plugs 1 at a time. Place each plug in a
tray marked with the corresponding cylinder numbers.
INSTALLATION PROCEDURE
1. Properly position each spark plug washer. 2. Inspect each spark plug gap. Adjust each plug as
needed.
Specification Spark plug gap: 1.52 mm (0.060 in)
NOTE: Refer to Fastener Notice in Service Precautions.
3. Hand start the spark plugs in the corresponding cylinders. 4. Tighten the spark plugs.
Tighten ^
For used heads tighten the spark plugs to 15 N.m (11 lb ft).
^ For new aluminum heads tighten the spark plugs to 20 N.m (15 lb ft).
^ For new iron heads, tighten the spark plugs to 30 N.m (22 lb ft).
5. Install the spark plug wires.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Compression Check > System Information > Specifications
Compression Check: Specifications
The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure
in any one cylinder is 1035 kPa (150 psi), the lowest allowable pressure for any other cylinder
would be 725 kPa (105 psi). (1035 x 70% = 725) (150 x 70% = 105).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Compression Check > System Information > System Diagnosis > Engine Compression Test (Electronic Throttle)
Compression Check: Testing and Inspection Engine Compression Test (Electronic Throttle)
Engine Compression Test (Electronic Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Turn the ignition to the ON position. 6.
Depress the accelerator pedal to position the throttle plate wide open. 7. Start with the compression
gauge at zero and crank the engine through four compression strokes, four puffs. 8. Check the
compression for each cylinder. Record the readings. 9. If a cylinder has low compression, inject
approximately 15 ml. (1 tablespoon) of engine oil into the combustion chamber through the spark
plug
hole. Recheck the compression and record the reading.
10. The minimum compression in any one cylinder should not be less than 70 percent of the
highest cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Then compression builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks >
Compression Check > System Information > System Diagnosis > Engine Compression Test (Electronic Throttle) > Page
4069
Compression Check: Testing and Inspection Engine Compression Test (Mechanical Throttle)
Engine Compression Test (Mechanical Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Block the throttle plate wide open. 6.
Start with the compression gauge at zero and crank the engine through four compression strokes,
four puffs. 7. Make the compression check for each cylinder. Record the reading. 8. If a cylinder
has low compression, inject approximately 15 ml. (1 tablespoon) of engine oil into the combustion
chamber through the spark plug
hole. Recheck the compression and record the reading.
9. The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Compression then builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Tune-up and Engine Performance Checks > Valve
Clearance > System Information > Specifications
Valve Clearance: Specifications
The manufacturer indicates that this vehicle has hydraulic lifters or adjusters and therefore does
not require adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications
Water Pump: Specifications
Water Pump Bolts (First Pass) ............................................................................................................
...................................................... 15 Nm (11 ft. lbs.) Water Pump Bolts (Final Pass) .......................
.......................................................................................................................................... 30 Nm (22
ft. lbs.) Water Pump Cover Bolts .........................................................................................................
................................................................. 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4076
Water Pump: Service and Repair
Water Pump Replacement (4.8L, 5.3L, and 6.0L Engines)
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the radiator inlet hose clip from the outlet duct. 4. Remove the air cleaner outlet duct.
5. If necessary, remove the engine sight shield. Refer to Engine Sight Shield Replacement (4.8L,
5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.8L, 5.3L, and 6.OL.
6. Remove the radiator vent inlet hose from the radiator hose clips.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4077
7. Reposition the inlet hose clamp at the water pump. 8. Remove the inlet hose from the water
pump. 9. Remove the fan blade. Refer to Fan Replacement.
10. Remove the accessory drive belt. Refer to Dive Belt Replacement - Accessory in Engine
Mechanical - 4.8L, 5.3L, and 6.OL.
11. Reposition the outlet hose clamp at the water pump. 12. Remove the outlet hose from the water
pump.
13. Reposition the surge tank outlet hose clamp at the water pump. 14. Remove the surge tank
outlet hose from the water pump.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4078
15. Reposition the heater inlet hose clamp at the water pump. 16. Remove the heater inlet hose
from the water pump.
17. Remove the water pump bolts. 18. Remove the water pump and gaskets. 19. Discard the water
pump gaskets.
Installation Procedure
Important: All gaskets surfaces are to be free of oil or other foreign material during assembly.
1. Install the water pump and NEW gaskets.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the water pump bolts. Tighten
2.1. Tighten the water pump bolts a first pass to 15 Nm (11 ft. lbs.).
2.2. Tighten the water pump bolts a final pass to 30 Nm (22 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4079
3. Install the heater inlet hose to the water pump. 4. Position the heater inlet hose clamp at the
water pump.
5. Install the surge tank outlet hose to the water pump. 6. Position the surge tank outlet hose clamp
at the water pump.
7. Install the outlet hose to the water pump. 8. Position the outlet hose clamp at the water pump. 9.
Install the accessory drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical
- 4.8L, 5.3L, and 6.01L.
10. Install the fan blade. Refer to Fan Replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4080
11. Install the inlet hose to the water pump. 12. Position the inlet hose clamp at the water pump.
13. Install the engine vent inlet hose to the radiator hose clips. 14. If necessary, install the engine
sight shield. Refer to Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or Engine
Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.81L, 5.3L, and 6.0L.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
15. Install the air cleaner outlet duct. 16. Install the radiator inlet hose clip to the outlet duct. 17.
Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Engine > Water Pump > Component Information >
Specifications > Page 4081
18. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Specifications
Cooling System Air Bleeder Pipe / Hose: Specifications
Engine Coolant Air Bleed Pipe and Cover Bolts
................................................................................................................................ 12 Nm (106 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Service and Repair > Coolant Air Bleed Pipe Assembly Replacement
Cooling System Air Bleeder Pipe / Hose: Service and Repair Coolant Air Bleed Pipe Assembly
Replacement
Coolant Air Bleed Pipe Assembly Replacement (4.8L, 5.3L, and 6.OL Engines)
Removal Procedure
1. Remove the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 4.8L,
5.31L, and 6.OL. 2. Remove the coolant air bleed pipe studs (1). 3. Remove the coolant air bleed
pipe (2) with gaskets (3).
4. Remove the coolant air bleed pipe cover bolts (1) and covers (2).
5. Remove the gaskets from the coolant air bleed pipe and covers. 6. Discard the gaskets.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Service and Repair > Coolant Air Bleed Pipe Assembly Replacement > Page 4088
7. Remove the coolant air bleed hose (1) from the pipe (2).
Installation Procedure
1. Install the coolant air bleed hose (1) onto the pipe (2).
Important: Install the gaskets properly onto the pipe and covers. Position the O-ring seal onto the
nipple portion of the pipe.
2. Install the gaskets onto the coolant air bleed pipe and covers.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Service and Repair > Coolant Air Bleed Pipe Assembly Replacement > Page 4089
3. Install the coolant air bleed pipe (2) and gaskets (3) onto the cylinder heads.
Notice: Refer to Fastener Notice in Cautions and Notices.
4. Install the coolant air bleed pipe studs (1).
- Tighten the coolant air bleed pipe studs to 12 Nm (106 inch lbs.).
5. Install the coolant air bleed pipe covers (2) and bolts (1).
- Tighten the coolant air bleed pipe cover bolts to 12 Nm (106 inch lbs.).
6. Install the intake manifold. Refer to Intake Manifold Replacement in Engine Mechanical - 4.81L,
5.31L, and 6.01L.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Service and Repair > Coolant Air Bleed Pipe Assembly Replacement > Page 4090
Cooling System Air Bleeder Pipe / Hose: Service and Repair Coolant Air Bleed Hose Replacement
Coolant Air Bleed Hose Replacement
Removal Procedure
1. If necessary, remove the engine sight shield. Refer to Engine Sight Shield Replacement (4.8L,
5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.81L, 5.31L, and 6.01L.
2. Reposition the coolant air bleed hose clamp at the throttle body. 3. Remove the coolant air bleed
hose from the throttle body.
4. Reposition the hose clamp at the pipe. 5. Remove the coolant air bleed hose (1) from the pipe
(2).
Installation Procedure
1. Install the coolant air bleed hose (1) to the pipe (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Cooling System Air Bleeder Pipe / Hose
> Component Information > Service and Repair > Coolant Air Bleed Pipe Assembly Replacement > Page 4091
2. Position the hose clamp at the pipe.
3. Install the coolant air bleed hose to the throttle body. 4. Position the coolant air bleed hose clamp
at the throttle body. 5. If necessary, install the engine sight shield. Refer to Engine Sight Shield
Replacement (4.8L, 5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.8L, 5.3L, and 6.OL.
6. Add engine coolant, if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Air Bleeder Screw, Coolant > Component
Information > Specifications
Air Bleeder Screw: Specifications
Coolant Air Bleed Pipe Stud/Bolt ..................................................................................................................................................... 12
Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Technical Service Bulletins > Cooling System - DEX-COOL(R) Coolant Leak Detection Dye
Coolant: Technical Service Bulletins Cooling System - DEX-COOL(R) Coolant Leak Detection Dye
Bulletin No.: 05-06-02-002B
Date: January 18, 2008
INFORMATION
Subject: DEX-COOL(R) Coolant - New Leak Detection Dye J 46366 - Replaces J 29545-6
Models: 1996-2008 GM Passenger Cars and Light/Medium Duty Trucks* (including Saturn)
1997-2008 Isuzu T-Series Medium Duty Tilt Cab Models Built in Janesville and Flint 1999-2008
Isuzu N-Series Medium Duty Commercial Models with 5.7L or 6.0L Gas Engine
2003-2008 HUMMER H2 2006-2008 HUMMER H3 2005-2008 Saab 9-7X
*EXCLUDING 2006 and Prior Chevrolet Aveo, Epica, Optra, Vivant and Pontiac Matiz, Wave
Supercede:
This bulletin is being revised to include additional model years. Please discard Corporate Bulletin
Number 05-06-02-002A (Section 06 - Engine/Propulsion System).
Leak detection dye P/N 12378563 (J 29545-6) (in Canada P/N 88900915) may cause
DEX-COOL(R) coolant to appear green in a black vessel making it appear to be conventional
(green) coolant. This may cause a technician to add conventional coolant to a low DEX-COOL(R)
system thus contaminating it. The green DEX-COOL(R) appearance is caused by the color of the
leak detection dye which alters the color of the DEX-COOL(R) coolant.
A new leak detection dye P/N 89022219 (J 46366) (in Canada P/N 89022220) has been released
that does not alter the appearance of the DEX-COOL(R) coolant. When adding the new leak
detection dye the color of the DEX-COOL(R) coolant will not change. For detecting leaks on any
system that uses DEX-COOL(R) leak detection dye P/N 89022219 (in Canada P/N 89022220)
should be used. The new leak detection dye can be used with both conventional and
DEX-COOL(R) coolant.
Disclaimer
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Technical Service Bulletins > Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 4099
Coolant: Technical Service Bulletins Cooling System - Coolant Recycling Information
Bulletin No.: 00-06-02-006D
Date: August 15, 2006
INFORMATION
Subject: Engine Coolant Recycling and Warranty Information
Models: 2007 and Prior GM Passenger Cars and Trucks (Including Saturn) 2007 and Prior
HUMMER Vehicles 2005-2007 Saab 9-7X
Attention:
Please address this bulletin to the Warranty Claims Administrator and the Service Manager.
Supercede:
This bulletin is being revised to adjust the title and Include Warranty Information. Please discard
Corporate Bulletin Number 00-06-02-006C (Section 06 - Engine/Propulsion System).
Coolant Reimbursement Policy
General Motors supports the use of recycled engine coolant for warranty repairs/service, providing
a GM approved engine coolant recycling system is used. Recycled coolant will be reimbursed at
the GMSPO dealer price for new coolant plus the appropriate mark-up. When coolant replacement
is required during a warranty repair, it is crucial that only the relative amount of engine coolant
concentrate be charged, not the total diluted volume. In other words: if you are using two gallons of
pre-diluted (50:50) recycled engine coolant to service a vehicle, you may request reimbursement
for one gallon of GM Goodwrench engine coolant concentrate at the dealer price plus the
appropriate warranty parts handling allowance.
Licensed Approved DEX-COOL(R) Providers
Important:
USE OF NON-APPROVED VIRGIN OR RECYCLED DEX-COOL(R) OR DEVIATIONS IN THE
FORM OF ALTERNATE CHEMICALS OR ALTERATION OF EQUIPMENT, WILL VOID THE GM
ENDORSEMENT, MAY DEGRADE COOLANT SYSTEM INTEGRITY AND PLACE THE
COOLING SYSTEM WARRANTY UNDER JEOPARDY.
Shown in Table 1 are the only current licensed and approved providers of DEX-COOL(R). Products
that are advertised as "COMPATIBLE" or "RECOMMENDED" for use with DEX-COOL(R) have not
been tested or approved by General Motors. Non-approved coolants may degrade the
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Technical Service Bulletins > Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 4100
coolant system integrity and will no longer be considered a 5 yr/150,000 mile (240,000 km) coolant.
Coolant Removal Services/Recycling
The tables include all coolant recycling processes currently approved by GM. Also included is a
primary phone number and demographic information. Used DEX-COOL(R) can be combined with
used conventional coolant (green) for recycling. Depending on the recycling service and/or
equipment, it is then designated as a conventional 2 yr/30,000 mile (50,000 km) coolant or
DEX-COOL(R) 5 yr/150,000 mile (240,000 km) coolant. Recycled coolants as designated in this
bulletin may be used during the vehicle(s) warranty period.
DEX-COOL(R) Recycling
The DEX-COOL(R) recycling service listed in Table 2 has been approved for recycling waste
engine coolants (DEX-COOL) or conventional) to DEX-COOL(R) with 5 yr/150,000 mile (240,000
km) usability. Recycling Fluid Technologies is the only licensed provider of Recycled
DEX-COOL(R) meeting GM6277M specifications and utilizes GM approved inhibitor packages.
This is currently a limited program being monitored by GM Service Operations which will be
expanded as demand increases.
Conventional (Green) Recycling
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Technical Service Bulletins > Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 4101
Processes shown in the Table 3 are capable of recycling waste engine coolants (DEX-COOL(R) or
conventional) to a conventional (green) coolant. Recycling conventional coolant can be
accomplished at your facility by a technician using approved EQUIPMENT (listed by model number
in Table 3), or by an approved coolant recycling SERVICE which may recycle the coolant at your
facility or at an offsite operation. Refer to the table for GM approved coolant recyclers in either of
these two categories. Should you decide to recycle the coolant yourself, strict adherence to the
operating procedures is imperative. Use ONLY the inhibitor chemicals supplied by the respective
(GM approved) recycling equipment manufacturer.
Sealing Tablets
Cooling System Sealing Tablets (Seal Tabs) should not be used as a regular maintenance item
after servicing an engine cooling system. Discoloration of coolant can occur if too many seal tabs
have been inserted into the cooling system. This can occur if seal tabs are repeatedly used over
the service life of a vehicle. Where appropriate, seal tabs may be used if diagnostics fail to repair a
small leak in the cooling system. When a condition appears in which seal tabs may be
recommended, a specific bulletin will be released describing their proper usage.
Water Quality
The integrity of the coolant is dependent upon the quality of DEX-COOL(R) and water.
DEX-COOL(R) is a product that has enhanced protection capability as well as an extended service
interval. These enhanced properties may be jeopardized by combining DEX-COOL(R) with poor
quality water. If you suspect the water in your area of being poor quality, it is recommended you
use distilled or de-ionized water with DEX-COOL(R).
"Pink" DEX-COOL(R)
DEX-COOL(R) is orange in color to distinguish it from other coolants. Due to inconsistencies in the
mixing of the dyes used with DEX-COOL(R), some batches may appear pink after time. The color
shift from orange to pink does not affect the integrity of the coolant, and still maintains the 5
yr/150,000 mile (240,000 km) service interval.
Back Service
Only use DEX-COOL(R) if the vehicle was originally equipped with DEX-COOL(R).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Technical Service Bulletins > Cooling System - DEX-COOL(R) Coolant Leak Detection Dye > Page 4102
Contamination
Mixing conventional green coolant with DEX-COOL(R) will degrade the service interval from 5
yrs./150,000 miles (240,000 km) to 2 yrs./30,000 miles (50,000 km) if left in the contaminated
condition. If contamination occurs, the cooling system must be flushed twice immediately and
re-filled with a 50/50 mixture of DEX-COOL(R) and clean water in order to preserve the enhanced
properties and extended service interval of DEX-COOL(R).
After 5 years/150,000 miles (240,000 km)
After 5 yrs/150,000 miles (240,000 km), the coolant should be changed, preferably using a coolant
exchanger. If the vehicle was originally equipped with DEX-COOL(R) and has not had problems
with contamination from non-DEX-COOL(R) coolants, then the service interval remains the same,
and the coolant does not need to be changed for another 5 yrs/150,000 miles (240,000 km)
Equipment (Coolant Exchangers)
The preferred method of performing coolant replacement is to use a coolant exchanger. A coolant
exchanger can replace virtually all of the old coolant with new coolant. Coolant exchangers can be
used to perform coolant replacement without spillage, and facilitate easy waste collection. They
can also be used to lower the coolant level in a vehicle to allow for less messy servicing of cooling
system components. It is recommended that you use a coolant exchanger with a vacuum feature
facilitates removing trapped air from the cooling system. This is a substantial time savings over
repeatedly thermo cycling the vehicle and topping-off the radiator. The vacuum feature also allows
venting of a hot system to relieve system pressure. Approved coolant exchangers are available
through the GMDE (General Motors Dealer Equipment) program.
For refilling a cooling system that has been partially or fully drained for repairs other than coolant
replacement, the Vac-N-Fill Coolant Refill Tool (GE-47716) is recommended to facilitate removal of
trapped air from the cooling system during refill.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Specifications > Capacity Specifications
Coolant: Capacity Specifications
Add one liter if equipped with rear heating for all engines.
Cooling System Capacity VORTEC 4800 V8 Automatic with Front A/C 14.4 qt (US)
VORTEC 4800 V8 Automatic with Front and Rear A/C 15.8 qt (US)
VORTEC 5300 V8 Automatic with Front A/C 14.4 qt (US)
VORTEC 5300 V8 Automatic with Front and Rear A/C 15.8 qt (US)
Vehicles equipped with optional air conditioner.
VORTEC 6000 V8 Automatic 15.8 qt (US)
VORTEC 6000 V8 Automatic with engine oil cooler 15.4 qt (US)
Vehicles equipped with optional engine cooler
VORTEC 8100 V8 Automatic 20.7 qt (US)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant > Component Information >
Specifications > Capacity Specifications > Page 4105
Coolant: Fluid Type Specifications
Engine Coolant 50/50 mixture of clean, drinkable water and use only GM Goodwrench DEX-COOL
or Havoline DEX-COOL Coolant.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Drain Plug, Cylinder Block >
Component Information > Specifications
Coolant Drain Plug: Specifications
Engine Block Coolant Drain Plugs
...........................................................................................................................................................
60 Nm (44 ft. lbs.) Cylinder Head Coolant Plug ...................................................................................
.................................................................................. 20 Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement
Coolant Line/Hose: Service and Repair Radiator Vent Inlet Hose Replacement
Radiator Vent Inlet Hose Replacement
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Reposition the vent
inlet hose clamp from the radiator. 3. Remove the vent inlet hose from the radiator. 4. Reposition
the vent inlet hose clamp from the surge tank. 5. Remove the vent inlet hose from the surge tank.
Installation Procedure
1. Install the vent inlet hose to the surge tank. 2. Reposition the vent inlet hose clamp to the surge
tank. 3. Install the vent inlet hose to the radiator. 4. Reposition the vent inlet hose clamp to the
radiator. 5. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4113
Coolant Line/Hose: Service and Repair Surge Tank Hose/Pipe Replacement - Inlet
Surge Tank Hose/Pipe Replacement - Inlet
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Reposition the surge
tank inlet hose clamp from the radiator. 3. Remove the surge tank inlet hose from the radiator.
4. Reposition the surge tank inlet hose clamp at the surge tank. 5. Remove the surge tank inlet
hose (1) from the surge tank.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4114
1. Install the surge tank inlet hose (1) to the surge tank. 2. Position the surge tank inlet hose clamp
to the surge tank.
3. Install the surge tank inlet hose to the radiator. 4. Position the surge tank inlet hose clamp to the
radiator. 5. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4115
Coolant Line/Hose: Service and Repair Surge Tank Hose/Pipe Replacement - Outlet
Surge Tank Hose/Pipe Replacement - Outlet (4.8L, 5.31-, and 6.0L Engines)
- Tools Required J 43181 Heater Line Quick Connect Release Tool
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct.
4. If equipped without regular production option (RPO) C36 auxiliary heater, remove the surge
tank/heater outlet hose (1) from the mounting clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4116
5. If equipped with RPO C36 auxiliary heater, remove the surge tank theater outlet hose (1) from
the mounting clip.
6. Install the J 43181 to the surge tank outlet hose. 7. Close the J 43181 around the surge tank
outlet hose. 8. Firmly pull the J 43181 into the quick connect end of the outlet hose.
9. If equipped without RPO C36 auxiliary heater, firmly grasp the outlet hose. Pull the outlet hose in
order to disengage the hose from the heater and
blower module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4117
10. If equipped with RPO C36 auxiliary heater, firmly grasp the outlet hose. Pull the outlet hose in
order to disengage the hose from the heater and
blower module.
11. Reposition the surge tank outlet hose clamp at the surge tank. 12. Remove the surge tank
outlet hose (2) from the surge tank.
13. Reposition the surge tank outlet hose clamp at the water pump. 14. Remove the surge tank
outlet hose from the water pump. 15. Remove the surge tank outlet hose.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4118
1. Install the surge tank outlet hose. 2. Install the surge tank outlet hose to the water pump. 3.
Position the surge tank outlet hose clamp to the water pump.
4. Install the surge tank outlet hose (2) to the surge tank. 5. Position the surge tank outlet hose
clamp to the surge tank.
6. If equipped with RPO C36 auxiliary heater, connect the surge tank outlet hose to the heater and
blower module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4119
7. If equipped without RPO C36 auxiliary heater, connect the surge tank outlet hose to the heater
and blower module.
Firmly push the hose onto the heater and blower module pipe until an audible click is heard.
8. If equipped with RPO C36 auxiliary heater, install the surge tank/heater outlet hose (1) to the
mounting clip.
9. If equipped without RPO C36 auxiliary heater, install the surge tank/heater outlet hose (1) to the
mounting clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Line/Hose > Component
Information > Service and Repair > Radiator Vent Inlet Hose Replacement > Page 4120
10. Install the air cleaner outlet duct.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
11. Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
12. Fill the cooling system, Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Reservoir > Component
Information > Specifications
Coolant Reservoir: Specifications
Surge Tank Bolt/Nut ............................................................................................................................
................................................... 9 Nm (80 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Reservoir > Component
Information > Specifications > Page 4124
Coolant Reservoir: Service and Repair
Surge Tank Replacement
Removal Procedure
1, Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Remove the air
cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls - 4.81L, 5.31L,
and 6.01L or Air Cleaner
Assembly Replacement in Engine Controls - 8.1 L.
3. Remove the surge tank overflow hose from the surge tank.
4. Disconnect the low coolant level switch electrical connector (3).
5. Reposition the surge tank inlet hose clamp. 6. Remove the surge tank inlet (1) hose from the
surge tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Reservoir > Component
Information > Specifications > Page 4125
7. Reposition the surge tank outlet hose clamp. 8. Remove the surge tank outlet hose (2) from the
surge tank.
9. Remove the bolt from the surge tank.
10. Remove the nut from the surge tank. 11. Remove the surge tank.
Installation Procedure
1. Install the surge tank.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the bolt to the surge tank.
- Tighten the bolt to 9 Nm (80 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Reservoir > Component
Information > Specifications > Page 4126
3. Install the nut to the surge tank.
- Tighten the nut to 9 Nm (80 inch lbs.).
4. Install the surge tank outlet hose (2) to the surge tank. 5. Position the surge tank outlet hose
clamp.
6. Install the surge tank inlet hose (1) to the surge tank. 7. Position the surge tank inlet hose clamp.
8. Connect the low coolant level switch electrical connector (3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Coolant Reservoir > Component
Information > Specifications > Page 4127
9. Install the surge tank overflow hose.
10. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine
Controls - 4.8L, 5.3L, and 6.01L or Air Cleaner Assembly
Replacement in Engine Controls - 8.1 L.
11. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Blade >
Component Information > Service and Repair
Fan Blade: Service and Repair
Fan Replacement
- Tools Required J 41240 Fan Clutch Remover and Installer
- J 41240-5A Fan Clutch Wrench
Removal Procedure
1. Remove the upper fan shroud. Refer to Fan Shroud Replacement - Upper (WIO M74) or Fan
Shroud Replacement Upper (WIM74). 2. Install the J 41240 to the fan clutch.
3. Remove the fan blade. 4. Lay the fan blade face down on a workbench.
5. Remove the fan clutch bolts from the rear of the fan blade, if necessary. 6. Separate the fan
clutch from the fan blade.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Blade >
Component Information > Service and Repair > Page 4132
Installation Procedure
Caution: Do not use or attempt to repair a damaged cooling fan assembly. Replace damaged fans
with new assemblies. An unbalanced cooling fan could fly apart causing personal Injury and
property damage.
1. Install the fan clutch bolts. 2. Install the fan clutch onto the fan blade, if necessary.
Notice: Refer to Fastener Notice in Cautions and Notices.
3. Install the fan clutch bolts.
- Tighten the bolts to 23 Nm (17 ft. lbs.).
4. Install the fan blade.
5. Install the J 41240 to the fan clutch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Blade >
Component Information > Service and Repair > Page 4133
- Tighten the fan clutch nut to 56 Nm (41 ft. lbs.).
6. Install the upper fan shroud. Refer to Fan Shroud Replacement - Upper (WIO M74) or Fan
Shroud Replacement - Upper (WIM74).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > A/T - Intermittent Downshift/Slip/Cycling Diagnosis
Fan Clutch: Technical Service Bulletins A/T - Intermittent Downshift/Slip/Cycling Diagnosis
File In Section: 07 Transmission/Transaxle
Bulletin No.: 99-07-30-016B
Date: October, 2002
INFORMATION
Subject: Diagnostic Information For Intermittent Transmission Downshift, Slip, Busy/cycling TCC or
Noisy Cooling Fan
Models: 1999-2000 Cadillac Escalade 2002-2003 Cadillac Escalade, Escalade EXT 1988-2003
Chevrolet Astro, Blazer, S-10, Silverado, Suburban 1989-2003 Chevrolet/Geo Tracker 1995-2003
Chevrolet Tahoe 1996-2003 Chevrolet Express 1988-1994 GMC S-15 1988-1999 GMC Suburban
1988-2003 GMC Safari, Sierra 1995-2003 GMC Sonoma, Yukon, Yukon XL 1996-2003 GMC
Savana 1999-2001 GMC Envoy 1991-2001 Oldsmobile Bravada 2003 HUMMER H2 with Air
Conditioning
This bulletin is being revised to change the Model information and text. Please discard Corporate
Bulletin Number 99-07-30-016A (Section 07 - Transmission/Transaxle)
Some customers may comment that at times the transmission seems to slip, or that there is a loud
roar from the engine with slow acceleration. This condition is most noticeable after the vehicle has
sat idle for 12 or more hours, or on hot days when the A/C is on and the vehicle moves slowly with
traffic.
Typical comments from customers may include the following conditions:
^ Intermittent slipping
^ Intermittent downshift followed by an upshift, both with no apparent reason
^ Busyness or cycling of the TCC (torque converter clutch) at steady throttle conditions and on a
level roadway
^ Noisy cooling fan
The type of concern described above requires further definition. The customer should be asked the
following questions:
^ Is the situation more pronounced with higher vehicle loads such as when pulling a trailer?
^ Do warmer ambient temperatures make the situation more pronounced?
^ When the condition occurred, did you have the A/C on, and were you driving in stop and go city
traffic?
^ Does the condition exhibit itself on the first start-up after sitting more than eight hours?
If the customer indicates that these conditions apply, and your observation confirms that the vehicle
is operating properly, provide the customer with the vehicle operating description included at the
end of this bulletin. Further action may not be necessary. A service procedure follows if further
definition is required.
Diagnostic Aids
Cooling fan operation or the resulting sound varies. The cooling fan clutch may be described as a
continuously variable clutch. If the vehicle engine is running, the fan blade is always turning unless
the fan clutch is non-functional. The speed of the fan in relation to engine speed is temperature
dependent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > A/T - Intermittent Downshift/Slip/Cycling Diagnosis > Page 4138
Maximum fan speed (air flow and related fan noise) through the engine compartment is
experienced under two conditions.
1. When the vehicle sits in an unused condition for several hours, the viscous fluid within the
thermostatic fan clutch assembly migrates and fully engages the clutch of the fan. After a short
drive, the viscous fluid will migrate to the storage area in the fan clutch and the fan clutch will slip,
reducing the noise (roar of the fan). This is normal thermostatic fan clutch operation.
2. When the engine is running, and the air being drawn by the fan or pushed through the radiator
from the vehicle movement reaches a high enough temperature, the fan clutch will fully engage the
fan clutch, drawing additional air through the radiator to lower the engine coolant temperature and
A/C refrigerant temperature. When the cooling fan clutch fully engages, fan noise increases (for
example; this is the same as switching an electric household fan from low to high speed). Some
customers have interpreted this sound increase to be an increase in the engine RPM due to
transmission downshift, transmission slipping, or TCC cycling. As the engine coolant temperature
decreases, the fan clutch will begin to slip, lowering the actual speed of the fan blade and the
resultant sound.
Service Procedure
When diagnosing an intermittent transmission downshift, slip, or busy/cycling TCC, follow these
steps:
1. Verify the transmission fluid level and the fluid condition. Refer to the Automatic Transmission
sub-section of the appropriate Service Manual.
2. Test drive the vehicle under the conditions described by the customer (ambient temperature,
engine coolant temperature, trailering, etc.). It may be necessary to partially restrict airflow to the
radiator in order to raise the engine coolant temperature to match the customer's conditions.
3. Monitor the engine RPM and the engine coolant temperature using a scan tool.
4. Listen for an actual increase in the engine RPM. Use either the vehicle tachometer (if equipped),
the Tech 2 RPM or transmission slip speed as an indicator, rather than just the sound.
If the engine RPM display on the tachometer or the Tech 2 increases, verify the scan tool RPM and
coolant temperature readings. If the noise increase is due to the engagement of the fan, the engine
RPM will not increase and the engine coolant temperature will begin to decrease after the fan
engages. As the fan runs, the engine coolant temperature will drop and the fan will disengage,
reducing noise levels. The engine RPM will not decrease. This cycle will repeat as the engine
coolant temperature rises again.
If the above procedure shows the condition to be cooling fan-related, no further action is
necessary. The vehicle should be returned to the customer and the condition explained.
If the above procedure shows the condition to be other than cooling fan-related, refer to the
Automatic Transmission sub-section of the appropriate Service Manual for transmission diagnosis
information.
The following information regarding the operation of the engine cooling fan should be photocopied
and given to the customer.
Intermittent Transmission Downshift
All light duty trucks are equipped with a thermostatic engine cooling fan. This fan is designed to
provide greater fuel efficiency and quieter operation than a standard fan. These benefits are
possible through the addition of a thermostatic clutch to the fan drive. When the engine is cool (it
the engine has been run in the last few hours), the clutch allows the fan to "slip" or turn at a speed
slower than the engine. By turning at a slower speed, the fan uses less horsepower, which saves
fuel, and is quieter. When the engine temperature reaches a preset temperature or if the engine
has not been run for several hours, the fan "engages" and turns at the same speed as the engine.
"Engagement" of the fan provides increased airflow through the radiator to cool the engine. As the
airflow increases, fan operation becomes clearly audible.
This increase in noise can easily be mistaken for an increase in engine RPM and may be
incorrectly blamed on the automatic transmission. When operating an unloaded vehicle in cooler
ambient temperatures, the thermostatic clutch usually won't fully engage. However, if the vehicle is
pulling a trailer, is heavily loaded or is operated at high ambient temperatures, the thermostatic fan
clutch may cycle on and off as the engine coolant temperature rises and falls.
The sound of fan operation under the conditions described above is a sign that the cooling system
on your vehicle is working correctly. Replacement or modification of the cooling system or the
transmission parts will not change or reduce the noise level. Attempts to reduce this noise may
cause you, the customer, to believe that your vehicle is not reliable and will inconvenience you by
causing your vehicle to be out of service.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > A/T - Intermittent Downshift/Slip/Cycling Diagnosis > Page 4139
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > Page 4140
Fan Clutch: Specifications
Fan Clutch Bolt ....................................................................................................................................
..................................................... 23 Nm (17 ft. lbs.) Fan Clutch Nut .................................................
......................................................................................................................................... 56 Nm (41
ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > Page 4141
Fan Clutch: Service and Repair
Fan Clutch Replacement
- Tools Required J 41240 Fan Clutch Remover and Installer
- J 41240-5A Fan Clutch Wrench
Removal Procedure
1. Remove the upper fan shroud. Refer to Fan Shroud Replacement - Upper (IMIO M74) or Fan
Shroud Replacement Upper (WIM74). 2. Install the J 41240 to the fan clutch.
3. Remove the fan blade. 4. Lay the fan blade face down on a workbench.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > Page 4142
5. Remove the fan clutch bolts from the rear of the fan blade. 6. Separate the fan clutch from the
fan blade.
Installation Procedure
1. Install the fan clutch bolts. 2. Install the fan clutch onto the fan blade.
Notice: Refer to Fastener Notice in Cautions and Notices.
3. Install the fan clutch bolts.
- Tighten the bolts to 23 Nm (17 ft. lbs.).
4. Install the fan blade.
5. Install the J 41240 to the fan clutch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Cooling Fan > Fan Clutch >
Component Information > Technical Service Bulletins > Page 4143
- Tighten the fan clutch nut to 56 Nm (41 ft. lbs.).
6. Install the upper fan shroud. Refer to Fan Shroud Replacement - Upper (W10 M74) or Fan
Shroud Replacement - Upper (WIM74).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Engine - Coolant Temperature
Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Engine - Coolant Temperature
Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations > Page 4148
Engine Coolant Temperature (ECT) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Engine - Coolant Temperature
Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations > Page 4149
Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Engine - Coolant Temperature
Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component Information > Locations > Page 4150
1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Specifications
Fan Shroud: Specifications
Fan Shroud Bolt ...................................................................................................................................
................................................... 9 Nm (80 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper
Fan Shroud: Service and Repair Fan Shroud - Upper
W/RPO M74
Fan Shroud Replacement - Upper (W/M74)
Removal Procedure
1. Loosen the air cleaner outlet duct clamps from the throttle body. 2. Loosen the air cleaner outlet
duct clamps from the mass airflow sensor. 3. Remove the air cleaner outlet duct. 4. Remove the
A/C line retainer from the fan shroud.
5. Remove the engine harness clip from the PCM cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4156
6. Remove the TCM cover bolts. 7. Remove TCM cover from the fan shroud.
8. Loosen the TCM electrical connector bolts. 9. Disconnect the TCM electrical connectors (1).
10. Remove the TCM and cover.
11. Remove the fan shroud retainers.
12. Remove the fan shroud bolts 13. Remove the upper fan shroud.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4157
1. Install the upper fan shroud.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the fan shroud bolts.
- Tighten the bolts to 9 Nm (80 inch lbs.).
3. Install the fan shroud retainers.
4. Connect the TCM electrical connectors (1). 5. Install the TCM and cover. 6. Tighten the TCM
electrical connector bolts.
- Tighten - Tighten the bolts to 8 Nm (71 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4158
7. Install the TCM cover to the fan shroud. 8. Install the TCM cover bolts.
- Tighten the to 9 Nm (80 inch lbs.).
9. Install the engine harness clip to the PCM cover.
10. Install the A/C line retainer to the fan shroud. 11. Install the air cleaner outlet duct. 12. Tighten
the air cleaner outlet duct clamp at the throttle body.
- Tighten the clamp screws to 7 Nm (62 inch lbs.).
13. Tighten the air cleaner outlet duct clamp at the mass airflow sensor.
- Tighten the clamp screws to 7 Nm (62 inch lbs.).
W/O RPO M74
Fan Shroud Replacement - Upper (W/O M74)
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4159
1. Loosen the air cleaner outlet duct clamps from the throttle body. 2. Loosen the air cleaner outlet
duct clamps from the mass airflow sensor. 3. Remove the air cleaner outlet duct.
4. Remove the throttle body heater hose retainer from the fan shroud. 5. Remove the inlet radiator
hose retainer from the fan shroud. 6. Remove the fan shroud retainers.
7. Remove the fan shroud bolts 8. Remove the upper fan shroud.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4160
1. Install the upper fan shroud.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the fan shroud bolts.
- Tighten the bolts to 9 Nm (80 inch lbs.).
3. Install the fan shroud retainers. 4. Install the inlet radiator hose retainer to the fan shroud 5.
Install the throttle body heater hose retainer to the fan shroud.
6. Install the air cleaner outlet duct. 7. Tighten the air cleaner outlet duct clamp at the throttle body.
- Tighten the clamp screw to 7 Nm (62 inch lbs.).
8. Tighten the air cleaner outlet duct clamp at the mass airflow sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4161
- Tighten the clamp screw to 7 Nm (62 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Fan Shroud > Component Information >
Service and Repair > Fan Shroud - Upper > Page 4162
Fan Shroud: Service and Repair Fan Shroud - Lower
Fan Shroud Replacement - Lower
Removal Procedure
1. Remove the cooling fan. Refer to Fan Replacement. 2. If equipped with engine oil cooler,
remove the oil cooler hose clip from the lower fan shroud. 3. Lift the lower fan shroud up in order to
disengage the fan shroud from the retaining clips on the radiator.
Installation Procedure
1. Install the lower fan shroud to the retaining clips on the radiator and firmly push down. 2. If
equipped with the engine oil cooler, Install the oil cooler hose clip to the lower fan shroud. 3. Install
the cooling fan. Refer to Fan Replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Technical Service Bulletins > Cooling System, A/C - Aluminum Heater Cores/Radiators
Heater Core: Technical Service Bulletins Cooling System, A/C - Aluminum Heater Cores/Radiators
INFORMATION
Bulletin No.: 05-06-02-001A
Date: July 16, 2008
Subject: Information On Aluminum Heater Core and/or Radiator Replacement
Models: 2005 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2005
HUMMER H2
Supercede:
This bulletin is being revised to update the Warranty Information. Please discard Corporate Bulletin
Number 05-06-02-001 (Section 06 - Engine/Propulsion System).
Important:
2004-05 Chevrolet Aveo (Pontiac Wave, Canada Only) does not use DEX-COOL(R). Refer to the
flushing procedure explained later in this bulletin.
The following information should be utilized when servicing aluminum heater core and/or radiators
on repeat visits. A replacement may be necessary because erosion, corrosion, or insufficient
inhibitor levels may cause damage to the heater core, radiator or water pump. A coolant check
should be performed whenever a heater core, radiator, or water pump is replaced. The following
procedures/ inspections should be done to verify proper coolant effectiveness.
Caution:
To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot.
The cooling system will release scalding fluid and steam under pressure if the radiator cap or surge
tank cap is removed while the engine and radiator are still hot.
Important:
If the vehicle's coolant is low, drained out, or the customer has repeatedly added coolant or water
to the system, then the system should be completely flushed using the procedure explained later in
this bulletin.
Technician Diagnosis
^ Verify coolant concentration. A 50% coolant/water solution ensures proper freeze and corrosion
protection. Inhibitor levels cannot be easily measured in the field, but can be indirectly done by the
measurement of coolant concentration. This must be done by using a Refractometer J 23688
(Fahrenheit scale) or J 26568 (centigrade scale), or equivalent, coolant tester. The Refractometer
uses a minimal amount of coolant that can be taken from the coolant recovery reservoir, radiator or
the engine block. Inexpensive gravity float testers (floating balls) will not completely analyze the
coolant concentration fully and should not be used. The concentration levels should be between
50% and 65% coolant concentrate. This mixture will have a freeze point protection of -34 degrees
Fahrenheit (-37 degrees Celsius). If the concentration is below 50%, the cooling system must be
flushed.
^ Inspect the coolant flow restrictor if the vehicle is equipped with one. Refer to Service Information
(SI) and/or the appropriate Service Manual for component location and condition for operation.
^ Verify that no electrolysis is present in the cooling system. This electrolysis test can be performed
before or after the system has been repaired. Use a digital voltmeter set to 12 volts. Attach one test
lead to the negative battery post and insert the other test lead into the radiator coolant, making sure
the lead does not touch the filler neck or core. Any voltage reading over 0.3 volts indicates that
stray current is finding its way into the coolant. Electrolysis is often an intermittent condition that
occurs when a device or accessory that is mounted to the radiator is energized. This type of current
could be caused from a poorly grounded cooling fan or some other accessory and can be verified
by watching the volt meter and turning on and off various accessories or engage the starter motor.
Before using one of the following flush procedures, the coolant recovery reservoir must be
removed, drained, cleaned and reinstalled before refilling the system.
Notice:
^ Using coolant other than DEX‐COOL(R) may cause premature engine, heater core or
radiator corrosion. In addition, the engine coolant may require changing sooner, at 30,000 miles
(50,000 km) or 24 months, whichever occurs first. Any repairs would not be covered by your
warranty. Always use DEX‐COOL(R) (silicate free) coolant in your vehicle.
^ If you use an improper coolant mixture, your engine could overheat and be badly damaged. The
repair cost would not be covered by your warranty. Too much water in the mixture can freeze and
crack the engine, radiator, heater core and other parts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Technical Service Bulletins > Cooling System, A/C - Aluminum Heater Cores/Radiators > Page 4167
Flushing Procedures using DEX-COOL(R)
Important:
The following procedure recommends refilling the system with DEX-COOL(R), P/N 12346290 (in
Canada, use P/N 10953464), GM specification 6277M. This coolant is orange in color and has a
service interval of 5 years or 240,000 km (150,000 mi). However, when used on vehicles built prior
to the introduction of DEX-COOL(R), maintenance intervals will remain the same as specified in the
Owner's Manual.
^ If available, use the approved cooling system flush and fill machine (available through the GM
Dealer Equipment Program) following the manufacturer's operating instructions.
^ If approved cooling system flush and fill machine is not available, drain the coolant and dispose of
properly following the draining procedures in the appropriate Service Manual. Refill the system
using clear, drinkable water and run the vehicle until the thermostat opens. Repeat and run the
vehicle three (3) times to totally remove the old coolant or until the drained coolant is almost clear.
Once the system is completely flushed, refill the cooling system to a 50%-60% concentration with
DEX‐COOL(R), P/N 12346290 (in Canada, use P/N 10953464), GM specification 6277M,
following the refill procedures in the appropriate Service Manual.
If a Service Manual is not available, fill half the capacity of the system with 100% DEX-COOL(R),
P/N 12346290 (in Canada, use P/N 10953464), GM specification 6277M. Then slowly add clear,
drinkable water (preferably distilled) to the system until the level of the coolant mixture has reached
the base of the radiator neck. Wait two (2) minutes and reverify the coolant level. If necessary, add
clean water to restore the coolant to the appropriate level.
Once the system is refilled, reverify the coolant concentration using a Refractometer J 23688
(Fahrenheit scale) or J 26568 (centigrade scale) coolant tester, or equivalent. The concentration
levels should be between 50% and 65%.
Flushing Procedures using Conventional Silicated (Green Colored) Coolant
Important:
2004-2005 Chevrolet Aveo (Pontiac Wave, Canada Only) does not use DEX‐COOL(R).
The Aveo and Wave are filled with conventional, silicated engine coolant that is blue in color.
Silicated coolants are typically green in color and are required to be drained, flushed and refilled
every 30,000 miles (48,000 km). The Aveo and Wave are to be serviced with conventional, silicated
coolant. Use P/N 12378560 (1 gal) (in Canada, use P/N 88862159 (1 L). Refer to the Owner's
Manual or Service Information (SI) for further information on OEM coolant.
Important:
Do not mix the OEM orange colored DEX-COOL(R) coolant with green colored coolant when
adding coolant to the system or when servicing the vehicle's cooling system. Mixing the orange and
green colored coolants will produce a brown coolant which may be a customer dissatisfier and will
not extend the service interval to that of DEX-COOL(R). Conventional silicated coolants offered by
GM Service and Parts Operations are green in color.
^ If available, use the approved cooling system flush and fill machine (available through the GM
Dealer Equipment Program) following the manufacturer's operating instructions.
^ If approved cooling systems flush and fill machine is not available, drain coolant and dispose of
properly following the draining procedures in appropriate Service Manual. Refill the system using
clear, drinkable water and run vehicle until thermostat opens. Repeat and run vehicle three (3)
times to totally remove old coolant or until drained coolant is almost clear. Once the system is
completely flushed, refill the cooling system to a 50%-60% concentration with a good quality
ethylene glycol base engine coolant, P/N 12378560, 1 gal (in Canada, use P/N 88862159 1 L),
conforming to GM specification 1825M, or recycled coolant conforming to GM specification 1825M,
following the refill procedures in the appropriate Service Manual.
If a Service Manual is not available, fill half the capacity of the system with 100% good quality
ethylene glycol base (green colored) engine coolant, P/N 12378560 1 gal., (in Canada, use P/N
88862159 1 L) conforming to GM specification 1825M. Then slowly add clear, drinkable water
(preferably distilled) to system until the level of the coolant mixture has reached the base of the
radiator neck. Wait two (2) minutes and recheck coolant level. If necessary, add clean water to
restore coolant to the appropriate level.
Once the system is refilled, recheck the coolant concentration using a Refractometer J 23688
(Fahrenheit scale) or J 26568 (centigrade scale) coolant tester, or equivalent. Concentration levels
should be between 50% and 65%.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Technical Service Bulletins > Cooling System, A/C - Aluminum Heater Cores/Radiators > Page 4168
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Technical Service Bulletins > Page 4169
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Service and Repair > Heater Core Replacement
Heater Core: Service and Repair Heater Core Replacement
REMOVAL PROCEDURE
1. Remove the heater/vent module. See: Heating and Air Conditioning/Housing Assembly
HVAC/Service and Repair 2. Remove the heater core cover screws. 3. Remove the heater core
cover.
4. Remove the heater core.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Service and Repair > Heater Core Replacement > Page 4172
1. Install the heater core.
2. Install the heater core cover.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install heater core cover screws.
Tighten Tighten the screws to 1.6 Nm (14 lb in).
4. Install the heater/vent module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Service and Repair > Heater Core Replacement > Page 4173
Heater Core: Service and Repair Heater Core Replacement - Auxiliary
REMOVAL PROCEDURE
1. Remove the auxiliary HVAC module (4) from the vehicle. See: Heating and Air
Conditioning/Housing Assembly HVAC/Service and Repair
2. Remove the air temperature actuator (1) from the auxiliary HVAC module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Service and Repair > Heater Core Replacement > Page 4174
3. Remove the heater core cover (1) from the auxiliary HVAC module.
4. Remove the heater core (1) from the auxiliary HVAC module.
INSTALLATION PROCEDURE
1. Install the heater core (1) to the auxiliary HVAC module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Core > Component Information >
Service and Repair > Heater Core Replacement > Page 4175
2. Install the heater core cover (1) to the auxiliary HVAC module.
3. Install the air temperature actuator (1) to the auxiliary HVAC module.
4. Install the auxiliary HVAC module assembly (4) to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary
Heater Hose: Service and Repair Heater Pipe Replacement - Auxiliary
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the auxiliary heater pipes (1, 2) from the heater inlet and outlet tees (3, 4). 3. Loosen the
right front wheelhouse to gain access to the clamp behind the wheelhouse. Refer to Wheelhouse
Panel Replacement in Body Front
End.
4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
5. Remove the auxiliary heater pipes (2, 3) from the auxiliary heater core.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4180
6. Remove the heater/A/C tubes retaining nut (4) from the stud (1) at the frame (6). 7. Remove the
auxiliary heater pipes (2) from the clamps (5). 8. Remove the auxiliary heater pipes from the
vehicle.
INSTALLATION PROCEDURE
1. Install the auxiliary healer pipes to the vehicle. 2. Install the auxiliary heater pipes (2) to the
clamps (5).
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the heater/A/C tubes retaining nut (4)10 the stud (1) at the frame (6).
Tighten Tighten the heater/A/C tubes retaining nut to 7 N.m (62 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4181
4. Install the auxiliary heater pipes (2, 3) to the auxiliary heater core. 5. Lower the vehicle. Refer to
Lifting and Jacking the Vehicle. 6. Install the right front wheelhouse.
7. Install the auxiliary heater pipes (1, 2)10 the heater inlet and outlet tees (3, 4). 8. Fill the cooling
system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4182
Heater Hose: Service and Repair Heater Hose Replacement - Inlet
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the air intake tube. 3. Remove the heater and surge tank hoses from the mounting clip. 4.
Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4183
6. Remove the inlet heater hose from the water pump.
7. Remove the inlet heater hose.
INSTALLATION PROCEDURE
1. Install the inlet heater hose.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4184
2. Install the inlet heater hose to the water pump.
3. Connect the heater hose to the heater core. Firmly push the quick connect onto the heater core
pipe until you hear an audible click. 4. Install the heater and surge tank hoses to the mounting clip.
5. Install the air intake tube. 6. Fill the cooling system. Refer to Draining and Filling Cooling System
in Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
Service and Repair > Heater Pipe Replacement - Auxiliary > Page 4185
Heater Hose: Service and Repair Heater Hose Replacement - Outlet
REMOVAL PROCEDURE
1. Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 2.
Remove the air intake tube. 3. Remove the heater and surge tank hoses from the mounting clip. 4.
Squeeze the plastic retainer release tabs.
5. Pull the connection apart.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Heater Hose > Component Information >
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6. Remove the outlet heater hose from the water pump. 7. Reposition the outlet heater hose clamp
at the surge tank. 8. Remove the outlet heater hose from the surge tank.
9. Remove the outlet heater hose.
INSTALLATION PROCEDURE
1. Install the outlet heater hose.
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2. Install the outlet heater hose to the water pump. 3. Install the outlet heater hose to the surge
tank. 4. Install the outlet heater hose clamp to the surge tank.
5. Connect the heater and surge tank hoses to the heater core.
Firmly push the quick connect onto the heater core hose until you hear an audible click.
6. Install the heater and surge tank hoses to the mounting clip. 7. Install the air intake tube. 8. Fill
the cooling system. Refer to Draining and Filling Cooling System in Cooling System.
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Heater Hose: Service and Repair Heater and A/C Pipe Repair - Auxiliary
TOOLS REQUIRED
J 41425 A/C Line Repair Kit
Do not service the rear A/C or heater lines as a complete unit. Service the rear A/C or heater lines
as a sectional repair.
You can obtain the various sections of line through GMSPO.
Use the J 41425 when any of the following actions damage the rear A/C or heater lines:
- Rub-through
- Collision damage
- Leakage in the system
Minimum Tube Length Required Table
IMPORTANT: When you section the rear A/C or heater lines, ensure that the correct minimum
length remains in the straight part of the line on both sides of the splice.
Follow the Straight Line Repair procedure in order to repair line damage in a straight section of line.
Follow the Line Sectioning Repair procedure in order to repair any damage in a bend area. Do not
repair the rear A/C or heater lines in a bend area, replace the lines. Maintaining the original line
shape will prevent vibrations and rub-through.
Straight Line Repair 1. Recover the refrigerant, if repairing the A/C lines. Refer to Refrigerant
Recovery and Recharging. 2. Drain the coolant, if repairing the heater lines. Refer to Draining and
Filling Cooling System in Engine Cooling. 3. Raise and support the vehicle. Refer to Lifting and
Jacking the Vehicle. 4. Locate the area that requires repair. 5. Obtain a length of replacement line
to make the repair. 6. Use a tubing cutter in order to cut and remove the section of damaged line.
IMPORTANT: The length of the replacement line must be the same as the section being replaced.
7. Use a tubing cutter in order to cut the replacement line to length. 8. Use the cleaning pad from
the J41425 in order to clean any burrs or grease from the line ends. Be sure to clean at least 19
mm (0.75 in) from the
line ends.
9. Use the LOK prep sealant in order to prep the line ends.
10. Apply one drop of the J 41425-3 sealing compound to the outside of each end of the line. 11.
Insert the line ends into the LOK fitting. 12. Rotate the LOK fitting one complete turn in order to
evenly distribute the sealing compound around the lines. 13. Install the correct LOK fitting jaws into
the J 41425-1 tool. 14. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK
connector ends are positioned in the counter bores of the jaws.
IMPORTANT: Hold the J 41425-1 tool body with a 3/8" breaker bar.
15. Tighten the forcing screw of the J 41425-1 tool.
When fully seated, the LOK connector collars will bottom out on the center shoulder of the LOK
fitting.
16. Loosen the forcing screw and remove the J 41425-1 tool from the repaired line. 17. Repeat
Step 8 through Step 16 to repair the other end of the line. 18. Verify that the LOK fittings are
correctly installed. 19. Lower the vehicle.
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20. Refill the coolant, if drained. Refer to Draining and Filling Cooling System in Engine Cooling.
21. Evacuate and recharge the refrigerant, if repairing the A/C lines. Refer to Refrigerant Recovery
and Recharging.
Line Sectioning Repair 1. Recover the refrigerant, if repairing the A/C lines. Refer to Refrigerant
Recovery and Recharging. 2. Drain the coolant, if repairing the heater lines. Refer to Draining and
Filling Cooling System in Engine Cooling. 3. Raise and support the vehicle. Refer to Lifting and
Jacking the Vehicle. 4. Obtain a new A/C or heater line for sectioning.
IMPORTANT: Stagger the splices if repairing more than one line.
5. Scribe a mark on the line that will be sectioned. 6. Use a tubing cutter in order to cut the line or
lines being replaced. 7. Remove the section of line being replaced from the vehicle.
IMPORTANT: The length of the replacement line must be the same as the line being replaced.
8. Install the replacement line to the vehicle. 9. Use a tubing cutter in order to cut the replacement
line to length.
10. Use the cleaning pad from the J 41425 in order to clean any burrs or grease. Be sure to clean
at least 19 mm (0.75 in) from the A/C line. 11. Use the LOK prep sealant in order to prep the A/C or
heater line. 12. Apply one drop of the J 41425-3 sealing compound to the outside of each line end.
13. Insert the line ends into the LOK fitting. 14. Rotate the LOK fitting one complete turn in order to
evenly distribute the sealing compound around the lines. 15. Install the correct LOK fitting jaws into
the J41425-1 tool. 16. Install the J 41425-1 tool over the LOK connectors. Verify that the LOK
connector ends are positioned in the counter bores of the jaws. 17. Hold the tool body with a 3/8"
breaker bar. Turn the forcing screw until both of the connector collars bottom on the center
shoulder of the LOK
fitting.
18. Loosen the forcing screw. Remove the tool from the repaired line. 19. Verify that the LOK fitting
is correctly installed. 20. Lower the vehicle. 21. Refill the coolant, if drained. Refer to Draining and
Filling Cooling System in Engine Cooling. 22. Evacuate and recharge the refrigerant, if repairing
the A/C lines. Refer to Refrigerant Recovery and Recharging.
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions
Temperature Gauge: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4196
Electrical Symbols Part 2
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4197
Electrical Symbols Part 3
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4198
Electrical Symbols Part 4
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Temperature Gauge: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4205
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4206
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4207
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4208
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4209
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4210
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4211
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4212
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4213
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4214
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4216
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4217
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4218
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4219
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4221
Equivalents - Decimal And Metric Part 1
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4222
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4223
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4224
Conversion - English/Metric
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Diagram Information and Instructions > Page 4225
Temperature Gauge: Electrical Diagrams
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Diagrams.
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Temperature Gauge > Component Information > Diagrams > Page 4226
Temperature Gauge: Description and Operation
ENGINE COOLANT TEMPERATURE GAGE
The IPC displays the engine coolant temperature as determined by the PCM. The IPC receives a
class 2 message from the PCM indicating the engine coolant temperature. The engine coolant
temperature gage defaults to 75°C (160°F) or below when: ^
The PCM detects a malfunction in the engine coolant temperature sensor circuit.
^ The IPC detects a loss of class 2 communication with the PCM.
TRANSMISSION TEMPERATURE GAGE
The IPC displays the transmission temperature as determined by the PCM. The IPC receives a
class 2 message from the PCM indicating the transmission temperature. The transmission
temperature gage will default to 40°C (100°F) or below if: ^
The PCM detects a malfunction in the transmission temperature sensor circuit.
^ The IPC detects a loss of class 2 communications with the PCM.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Lamps and Indicators - Cooling System >
Temperature Gauge > Component Information > Diagrams > Page 4227
Temperature Gauge: Testing and Inspection
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Testing and Inspection.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator > Radiator Drain Plug >
Component Information > Service and Repair
Radiator Drain Plug: Service and Repair
Drain Cock Replacement
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Remove the radiator
drain cock.
Installation Procedure
1. Install the radiator drain cock. 2. Fill the cooling system. Refer to Draining and Filling Cooling
System.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Radiator Hose > Component Information
> Service and Repair > Radiator Hose Replacement - Inlet
Radiator Hose: Service and Repair Radiator Hose Replacement - Inlet
Radiator Hose Replacement - Inlet
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct. 4. If necessary, remove the engine sight shield. Refer to
Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (L09) in Engine Mechanical - 4.8L, 5.3L, and 6.OL.
5. Remove the radiator vent inlet hose from the radiator inlet hose clips.
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6. Reposition the inlet hose clamp from the radiator. 7. Remove the inlet hose from the radiator. 8.
Remove the inlet hose clip from the fan shroud.
9. Reposition the inlet hose clamp from the water outlet.
10. Remove the inlet hose from the water outlet.
Installation Procedure
1. Install the inlet hose to the water outlet. 2. Reposition the inlet hose clamp to the water outlet.
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3. Install the inlet hose clip to the fan shroud. 4. Install the inlet hose to the radiator. 5. Reposition
the inlet hose clamp to the radiator.
6. Install the radiator vent inlet hose to the radiator inlet hose clips. 7. If necessary, install the
engine sight shield, Refer to Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or
Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.8L, 5.31L, and 6.OL.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
8. Install the air cleaner outlet duct. 9. Tighten the air cleaner outlet duct clamps at the following
locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
10. Fill the cooling system. Refer to Draining and Filling Cooling System.
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> Service and Repair > Radiator Hose Replacement - Inlet > Page 4238
Radiator Hose: Service and Repair Radiator Hose Replacement - Outlet
Radiator Hose Replacement - Outlet (4.8L, 5.3L, and 6.OL Engines)
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the air cleaner outlet duct.
4. Reposition the outlet hose clamp from the water pump. 5. Remove the outlet hose from the
water pump.
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6. Reposition the outlet hose clamp from the radiator. 7. Remove the outlet hose from the radiator.
Installation Procedure
1. Install the outlet hose to the radiator. 2. Reposition the outlet hose clamp to the radiator.
3. Install the outlet hose to the water pump. 4. Reposition the outlet hose clamp to the water pump.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
5. Install the air cleaner outlet duct.
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6. Install the radiator inlet hose clip to the outlet duct. 7. Tighten the air cleaner outlet duct clamps
at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
8. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Sensors and Switches - Cooling System
> Engine - Coolant Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations
Locations View
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Sensors and Switches - Cooling System
> Engine - Coolant Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations > Page 4246
Engine Coolant Temperature (ECT) Sensor
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Sensors and Switches - Cooling System
> Engine - Coolant Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations > Page 4247
Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
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> Engine - Coolant Temperature Sensor/Switch > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations > Page 4248
1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions
Temperature Gauge: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Information > Diagrams > Diagram Information and Instructions > Page 4256
Electrical Symbols Part 4
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Temperature Gauge: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4275
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4276
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4277
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4278
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4279
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4280
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4281
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4282
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Diagram Information and Instructions > Page 4283
Temperature Gauge: Electrical Diagrams
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Diagrams.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Page 4284
Temperature Gauge: Description and Operation
ENGINE COOLANT TEMPERATURE GAGE
The IPC displays the engine coolant temperature as determined by the PCM. The IPC receives a
class 2 message from the PCM indicating the engine coolant temperature. The engine coolant
temperature gage defaults to 75°C (160°F) or below when: ^
The PCM detects a malfunction in the engine coolant temperature sensor circuit.
^ The IPC detects a loss of class 2 communication with the PCM.
TRANSMISSION TEMPERATURE GAGE
The IPC displays the transmission temperature as determined by the PCM. The IPC receives a
class 2 message from the PCM indicating the transmission temperature. The transmission
temperature gage will default to 40°C (100°F) or below if: ^
The PCM detects a malfunction in the transmission temperature sensor circuit.
^ The IPC detects a loss of class 2 communications with the PCM.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Temperature Gauge > Component
Information > Diagrams > Page 4285
Temperature Gauge: Testing and Inspection
For information regarding this component and the system that it is a part of, please refer to
Instrument Panel, Gauges and Warning Indicators, Testing and Inspection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Thermostat Housing, Engine Cooling >
Component Information > Specifications
Thermostat Housing: Specifications
Thermostat Housing Bolt .....................................................................................................................
..................................................... 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Thermostat Housing, Engine Cooling >
Component Information > Specifications > Page 4289
Thermostat Housing: Service and Repair
Thermostat Housing Replacement (4.8L, 5.3L, and 6.0L Engines)
Removal Procedure
Important: The thermostat is not serviceable separately. The water pump inlet and thermostat must
be replaced as an assembly.
1. Remove the radiator outlet hose. Refer to Radiator Hose Replacement - Outlet (4.8L, 5.3L, and
6.OL Engines) or Radiator Hose Replacement Outlet (8.1L Engine).
2. Remove the water pump inlet bolts. 3. Remove the water pump inlet and thermostat from the
water pump.
Installation Procedure
1. Install the thermostat and water pump inlet to the water pump.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the water pump inlet bolts.
- Tighten the water pump inlet bolts to 15 Nm (11 ft. lbs.).
3. Install the radiator outlet hose. Refer to Radiator Hose Replacement - Outlet (4.8L, 5.3L, and
6.OL Engines) or Radiator Hose Replacement Outlet (8.1L Engine).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications
Water Pump: Specifications
Water Pump Bolts (First Pass) ............................................................................................................
...................................................... 15 Nm (11 ft. lbs.) Water Pump Bolts (Final Pass) .......................
.......................................................................................................................................... 30 Nm (22
ft. lbs.) Water Pump Cover Bolts .........................................................................................................
................................................................. 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4293
Water Pump: Service and Repair
Water Pump Replacement (4.8L, 5.3L, and 6.0L Engines)
Removal Procedure
1. Drain the cooling system. Refer to Draining and Filling Cooling System. 2. Loosen the air cleaner
outlet duct clamps at the following locations:
- Throttle body
- Mass airflow/intake air temperature (MAF/IAT) sensor
3. Remove the radiator inlet hose clip from the outlet duct. 4. Remove the air cleaner outlet duct.
5. If necessary, remove the engine sight shield. Refer to Engine Sight Shield Replacement (4.8L,
5.3L, and 6.OL (LQ4) or Engine Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.8L, 5.3L, and 6.OL.
6. Remove the radiator vent inlet hose from the radiator hose clips.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4294
7. Reposition the inlet hose clamp at the water pump. 8. Remove the inlet hose from the water
pump. 9. Remove the fan blade. Refer to Fan Replacement.
10. Remove the accessory drive belt. Refer to Dive Belt Replacement - Accessory in Engine
Mechanical - 4.8L, 5.3L, and 6.OL.
11. Reposition the outlet hose clamp at the water pump. 12. Remove the outlet hose from the water
pump.
13. Reposition the surge tank outlet hose clamp at the water pump. 14. Remove the surge tank
outlet hose from the water pump.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4295
15. Reposition the heater inlet hose clamp at the water pump. 16. Remove the heater inlet hose
from the water pump.
17. Remove the water pump bolts. 18. Remove the water pump and gaskets. 19. Discard the water
pump gaskets.
Installation Procedure
Important: All gaskets surfaces are to be free of oil or other foreign material during assembly.
1. Install the water pump and NEW gaskets.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the water pump bolts. Tighten
2.1. Tighten the water pump bolts a first pass to 15 Nm (11 ft. lbs.).
2.2. Tighten the water pump bolts a final pass to 30 Nm (22 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4296
3. Install the heater inlet hose to the water pump. 4. Position the heater inlet hose clamp at the
water pump.
5. Install the surge tank outlet hose to the water pump. 6. Position the surge tank outlet hose clamp
at the water pump.
7. Install the outlet hose to the water pump. 8. Position the outlet hose clamp at the water pump. 9.
Install the accessory drive belt. Refer to Drive Belt Replacement - Accessory in Engine Mechanical
- 4.8L, 5.3L, and 6.01L.
10. Install the fan blade. Refer to Fan Replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4297
11. Install the inlet hose to the water pump. 12. Position the inlet hose clamp at the water pump.
13. Install the engine vent inlet hose to the radiator hose clips. 14. If necessary, install the engine
sight shield. Refer to Engine Sight Shield Replacement (4.8L, 5.3L, and 6.OL (LQ4) or Engine
Sight Shield
Replacement (6.OL (LQ9) in Engine Mechanical - 4.81L, 5.3L, and 6.0L.
Important: Align the arrow at the throttle body end of the duct with the throttle body attaching stud.
15. Install the air cleaner outlet duct. 16. Install the radiator inlet hose clip to the outlet duct. 17.
Tighten the air cleaner outlet duct clamps at the following locations:
- Throttle body
- MAF/IAT sensor
- Tighten the air cleaner outlet duct clamp screws to 7 Nm (62 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Cooling System > Water Pump > Component Information >
Specifications > Page 4298
18. Fill the cooling system. Refer to Draining and Filling Cooling System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair
Catalytic Converter: Service and Repair
Catalytic Converter Replacement (4.81- and 5.31- Engines)
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Remove the engine shield bolts and shield, if necessary.
3. Remove the oil pan skid plate bolts and plate, if necessary.
4. Unclip the oxygen sensor connection from the floor reinforcement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair > Page 4303
5. Remove the clip from around the engine harness and the oxygen sensor pigtail. 6. Disconnect
the connector position assurance (CPA) retainers. 7. Disconnect the oxygen sensor electrical
connectors.
8. Unclip the oxygen sensors electrical connectors from the following:
- Hose clip
- Transmission crossmember
9. Disconnect the CPA retainers.
10. Disconnect the oxygen sensor electrical connectors (1, 2).
11. Remove the left exhaust manifold pipe nuts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair > Page 4304
12. Remove the right exhaust manifold pipe nuts.
13. Remove the exhaust muffler nuts. 14. Remove the catalytic converter.
15. Remove the oxygen sensors if the catalytic converter is to be replaced.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair > Page 4305
Notice: Refer to Fastener Notice in Cautions and Notices.
1. If the catalytic converter was replaced, perform the following:
1.1. Apply anti-seize compound GM P/N 12377953 or equivalent to the threads of the old oxygen
sensors.
1.2. Install the oxygen sensors.
- Tighten the oxygen sensors to 42 Nm (31 ft. lbs.).
2. Install the catalytic convertor.
3. Install NEW exhaust manifold pipe seals to the exhaust manifolds. 4. Install the right exhaust
manifold pipe nuts until sung.
5. Install the left exhaust manifold pipe nuts until snug. 6. Tighten the right and left exhaust
manifold pipe nuts.
- Tighten the nuts to 50 Nm (39 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair > Page 4306
7. Install the exhaust muffler nuts.
- Tighten the nuts to 40 Nm (30 ft. lbs.).
8. Connect the oxygen sensor electrical connectors (1, 2). 9. Connect the CPA retainers.
10. Clip the oxygen sensors electrical connectors to the following:
- Hose clip
- Transmission crossmember
11. Connect the oxygen sensor electrical connectors. 12. Connect the CPA retainers. 13. Install the
clip around the engine harness and the oxygen sensor pigtail.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Catalytic Converter > Component
Information > Service and Repair > Page 4307
14. Clip the oxygen sensor connection to the floor reinforcement.
15. Install the oil pan skid plate and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.)
16. Install the engine shield and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
17. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Technical Service Bulletins > Engine - New Exhaust Manifold Bolts/Torque Specs
Exhaust Manifold: Technical Service Bulletins Engine - New Exhaust Manifold Bolts/Torque Specs
Bulletin No.: 06-06-01-026
Date: December 22, 2006
INFORMATION
Subject: L59, LR4, LM4, LM7, LQ4, LQ9, LS1, LS6 New Exhaust Manifold Bolts and Torque
Specifications for GEN III Vortec(TM) Engine
Models: 1999-2003 Cadillac Escalade 1999 Chevrolet Forward Control Chassis, P32 R/V Van
Chassis, P42 Commercial Chassis 1998-2002 Chevrolet Camaro 1999-2003 Chevrolet Corvette,
Express, Silverado, Suburban, Tahoe, W-Series Medium Duty Truck 1999 GMC Forward Control
Chassis, P32 R/V Van Chassis, P42 Commercial Chassis 1999-2003 GMC Savana, Siera, Yukon,
W-Series Medium Duty Truck 2003 GMC Siera Denali 1998-2002 Pontiac Firebird Formula,
Firebird Trans Am 2003 HUMMER H2 1999-2003 Isuzu N-Series Medium Duty Truck
with GEN III Vortec(TM) Engine (VINs V, G, P, S, T, N, U, Z, - RPOs 4.8L, 5.3L, 5.7L, 6.0L)
A new exhaust manifold bolt and torque specification was introduced to the GEN III Vortec(TM)
small block V8 engines beginning with the 2004 model year. When servicing any GEN III
Vortec(TM) small bock exhaust manifolds, the exhaust manifold bolts should be replaced.
- P/N 11518860 Exhaust Manifold Bolts
Apply a 5 mm (0.2 in) wide bead of high temperature threadlocker to the threads of the exhaust
manifold bolts before installing.
- P/N 12345493 - GM High Temperature High Strength Threadlocker (U.S.)
- P/N 10953488 - GM High Temperature High Strength Threadlocker (Canada)
When tightening the exhaust manifold bolts it should be done with two passes. First tighten the two
center bolts on the exhaust manifold. Then tighten the rest of the bolts, alternating from side to
side, while working towards the outside bolts.
Install the exhaust manifold bolts.
Refer to the following torque sequence:
Tighten
Tighten to 10 N.m (89 lb in) on the first pass.
Tighten to 20 N.m (15 lb ft) on the final pass.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Technical Service Bulletins > Engine - New Exhaust Manifold Bolts/Torque Specs > Page 4312
Exhaust Manifold: Technical Service Bulletins Engine - Revised Exhaust Manifold Bolts/Torque
Specs.
Subject: L59, LR4, LM4, LM7, LQ4, LQ9, LS1, LS6 New Exhaust Manifold Bolts and Torque
Specifications for GEN III Vortec Engine # 06-06-02-026 - (12/22/2006)
Models
A new exhaust manifold bolt and torque specification was introduced to the GEN III Vortec(TM)
small block V8 engines beginning with the 2004 model year. When servicing any GEN III
Vortec(TM) small block exhaust manifolds, the exhaust manifold bolts should be replaced.
- P/N 11518860 Exhaust Manifold Bolts
Apply a 5 mm (0.2 in) wide bead of high temperature threadlocker to the threads of the exhaust
manifold bolts before installing.
^ P/N 12345493 - GM High Temperature High Strength Threadlocker (U.S.)
^ P/N 10953488 - GM High Temperature High Strength Threadlocker (Canada)
Important:
When tightening the exhaust manifold bolts it should he done with two passes. First tighten the two
center bolts on the exhaust manifold. Then tighten the rest of the bolts alternating from side to side,
while working towards the outside bolts.
Install the exhaust manifold bolts. Refer to the following torque sequence:
Tighten
^ Tighten to 10 Nm (89 lb in) on the first pass.
^ Tighten to 20 Nm (15 lb ft) on the final pass.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Technical Service Bulletins > Page 4313
Exhaust Manifold: Specifications
Exhaust Manifold Bolts
(First Pass) ..........................................................................................................................................
.................................................. 15 Nm (11 ft. lbs.) (Final Pass) .........................................................
.................................................................................................................................. 25 Nm (18 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left
Exhaust Manifold: Service and Repair Exhaust Manifold Replacement - Left
Exhaust Manifold Replacement - Left (4.8L, 5.3L, and 6.0L- Engines)
Removal Procedure
1. Remove the ignition coils. 2. Remove the spark plugs. 3. Raise and suitably support the vehicle.
4. Remove the exhaust manifold pipe nuts. 5. Lower the vehicle.
6. Remove the exhaust manifold bolts, manifold, and gasket. 7. Discard the gasket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4316
8. Remove the heat shield bolts (3), and shield (2) from the exhaust manifold (1), if necessary. 9.
Clean and inspect the exhaust manifold, if the manifold is not being replaced.
Installation Procedure
Notice: Refer to Fastener Notice in Cautions and Notices.
1. Install the heat shield (2), and bolts (3) to the exhaust manifold (1), if necessary.
- Tighten the bolts to 9 Nm (80 inch lbs.).
Important:
- Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed
and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board
Diagnostics (OBD) II system performance.
- The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or
threadlocking material.
- Do not apply sealant to the first three threads of the bolt.
2. Apply a 5 mm (0.2 inch) wide band of threadlock GM P/N 12345493 or equivalent to the threads
of the exhaust manifold bolts. 3. Install the exhaust manifold, NEW gasket and bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4317
3.1. Tighten the exhaust manifold bolts a first pass to 15 Nm (11 ft. lbs.). Tighten the exhaust
manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the
outside bolts.
3.2. Tighten the exhaust manifold bolts a final pass to 25 Nm (18 ft. lbs.). Tighten the exhaust
manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the
outside bolts.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the
left cylinder head. 5. Raise the vehicle.
6. Install the exhaust manifold pipe nuts.
- Tighten the nuts to 50 Nm (37 ft. lbs.).
7. Lower the vehicle. 8. Install the spark plugs. Refer to Spark Plug Replacement in Engine
Controls -4.8L, 5.3L, and 6.OL. 9. Install the ignition coils. Refer to Ignition Coil(s) Replacement in
Engine Controls - 4.8L, 5.3L, and 6.OL.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4318
Exhaust Manifold: Service and Repair Exhaust Manifold Replacement - Right
Exhaust Manifold Replacement - Right (4.8L, 5.3L, and 6.01- Engines)
1. Remove the ignition coils. Refer to Ignition Coil(s) Replacement in Engine Controls - 4.8L, 5.3L,
and 6.OL. 2. Remove the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 4.8L,
5.3L, and 6.OL. 3. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle
in General Information. 4. Remove the exhaust manifold pipe nuts. 5. Lower the vehicle.
6. If equipped, remove the bolts (1, 2, and 3) attaching the exhaust gas recirculation (EGR) valve
pipe to the following:
- Intake manifold
- Cylinder head
- Exhaust manifold
7. Remove the EGR valve pipe and gaskets, if equipped.
With mild force, pull the EGR valve pipe from the intake manifold.
8. Remove the O-ring seal from the EGR valve pipe, if equipped. 9. Discard the gasket and the
O-ring seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4319
10. Remove the exhaust manifold bolts, manifold, and gasket. 11. Discard the gasket.
12. Remove the heat shield bolts (1), and shield (2) from the exhaust manifold (1), if necessary. 13.
Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in
Engine Mechanical - 4.81L, 5.31L, and 6.01- Unit
Repair.
Installation Procedure
Notice: Refer to Fastener Notice in Cautions and Notices.
1. Install the heat shield (2), and bolts (1) to the exhaust manifold (1), if necessary.
- Tighten the bolts to 9 Nm (80 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4320
Important:
- Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed
and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board
Diagnostics (OBD) II system performance.
- The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or
threadlocking material.
- Do not apply sealant to the first three threads of the bolt.
2. Apply a 5 mm (0.2 inch) wide band of threadlock GM P/N 12345493 or equivalent to the threads
of the exhaust manifold bolts. 3. Install the exhaust manifold, NEW gasket and bolts.
3.1. Tighten the exhaust manifold bolts a first pass to 15 Nm (11 ft. lbs.). Tighten the exhaust
manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the
outside bolts.
3.2. Tighten the exhaust manifold bolts a final pass to 25 Nm (18 ft. lbs.). Tighten the exhaust
manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the
outside bolts.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the front of
the right cylinder head.
5. Apply a light coating of clean engine oil to a NEW O-ring seal and install the seal onto the EGR
valve pipe. 6. Install the EGR pipe. 7. Install the EGR valve pipe bolts until snug.
7.1. Tighten the intake manifold bolt (1) to 10 Nm (89 inch lbs.).
7.2. Tighten the cylinder head bolts (2) to 50 Nm (37 ft. lbs.).
7.3. Tighten the exhaust manifold bolts (3) to 30 Nm (22 ft. lbs.).
8. Install the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 4.8L, 5.3L, and
6.OL. 9. Install the ignition coils. Refer to Ignition Coil(s) Replacement in Engine Controls - 4.8L,
5.3L, and 6.OL.
10. Raise the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Manifold > Component
Information > Service and Repair > Exhaust Manifold Replacement - Left > Page 4321
11. Install the exhaust manifold pipe nuts.
- Tighten the nuts to 50 Nm (37 ft. lbs.).
12. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Pipe > Component Information
> Specifications
Exhaust Pipe: Specifications
Exhaust Manifold Pipe Nut ..................................................................................................................
.................................................... 50 Nm (37 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Exhaust Pipe/Muffler Hanger >
Component Information > Specifications
Exhaust Pipe/Muffler Hanger: Specifications
Exhaust Manifold Pipe Hanger Bracket Bolt
...................................................................................................................................... 12 Nm (106
inch lbs.) Exhaust Muffler Hanger Nut .................................................................................................
................................................................... 50 Nm (39 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Customer Interest for Heat Shield: > 03-06-05-008D > Mar > 07 > Exhaust
System - Popping/Snapping Noise When Hot/Idling
Heat Shield: Customer Interest Exhaust System - Popping/Snapping Noise When Hot/Idling
Bulletin No.: 03-06-05-008D
Date: March 05, 2007
TECHNICAL
Subject: Exhaust Popping/Snapping Noise When Vehicle is Hot, at Idle, or Immediately After
Vehicle is Shut Off (Replace Muffler Heat Shield)
Models: 2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV
2002-2006 Chevrolet Avalanche, Suburban, Tahoe, Silverado, Silverado HD 2007 Chevrolet
Silverado Classic, Silverado HD Classic 2002-2006 GMC Sierra, Sierra HD , Yukon, Yukon Denali,
Yukon Denali XL 2007 GMC Sierra Classic, Sierra HD Classic 2003-2006 HUMMER H2
with 4.8L, 5.3L, 6.0L or 8.1L Gasoline Engine (VINs V, B, T, Z, N, V, G - RPOs LR4, L33, LM7,
L59, LQ9, LQ4, L18)
Supercede:
This bulletin is being revised to add the 2006 and 2007 (Classic Only) model years and the 5.3L
(L33) engine. Please discard Corporate Bulletin Number 03-06-05-008C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on a popping/snapping noise from underneath the vehicle at idle or
immediately after the vehicle is shut off. Some popping/snapping noise from the exhaust system
during cool down is a normal condition.
The noise may be intermittent depending on the outside temperature and or temperature of the
exhaust system at the time of testing.
Cause
As the exhaust system warms and cools, the muffler and the muffler heat shield expand and
contract at different rates and may cause a popping and/or snapping noise.
Some popping/snapping noise from the exhaust system during cool down is a normal condition.
The customer should be made aware that this service procedure is designed to reduce but not
eliminate all exhaust system popping and snapping during cool down.
Correction
Follow the service procedure below to correct this condition.
Some popping/snapping noise from the exhaust system during cool down is a normal condition.
The customer should be made aware that this service procedure is designed to reduce but not
eliminate all exhaust system popping and snapping during cool down.
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
In order to avoid being burned, do not service the exhaust system while it is still hot. Service the
system when it is cool.
Always wear protective goggles and gloves when removing exhaust parts as falling rust and sharp
edges could result in serious personal injury.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Customer Interest for Heat Shield: > 03-06-05-008D > Mar > 07 > Exhaust
System - Popping/Snapping Noise When Hot/Idling > Page 4336
Remove the nuts securing the muffler to the catalytic converter.
On 6.0L and 8.1L equipped vehicles only, loosen the exhaust pipe clamp.
Do not use oil base lubricants on the rubber exhaust hangers.
Apply a soapy solution to the exhaust pipe hanger rods in order to ease the removal of the exhaust
hangers.
Pry the exhaust hangers free from the exhaust pipe hanger rods.
It is not necessary to remove the muffler from the vehicle to replace the muffler heat shield.
Reposition the muffler to gain access to the muffler heat shield.
Use extreme caution not to damage the muffler when removing the heat shield from the muffler.
Using an air-powered hack saw blade, or equivalent, cut off the existing muffler heat shield just as
the heat shield rises off of the muffler. See the illustration above.
Remove the heat shield from the muffler.
Hammer flush the remaining heat shield to the muffler.
The new heat shield should not come in contact with the remaining muffler heat shield. The new
heat shield should not come in contact with the horizontal lock seam on the muffler.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Customer Interest for Heat Shield: > 03-06-05-008D > Mar > 07 > Exhaust
System - Popping/Snapping Noise When Hot/Idling > Page 4337
Install the new heat shield (see parts list below) onto the muffler as shown above.
Install three straps, P/N 10391259, so that the strap screw head will be located on top of the
muffler.
Tighten
Tighten the strap screw to 4 N.m (35 lb in).
Cut off the excess strap material and bend the strap over the strap screw head as indicated above.
Remove the exhaust pipe clamp.
ONLY 6.0L and 8.1L equipped vehicles require a new exhaust pipe clamp, P/N 15103174.
On 6.0L and 8.1L equipped vehicles only, install a new exhaust pipe clamp, P/N 15103174, on the
exhaust pipe.
Reposition the muffler in the correct position.
Slide the muffler forward into position, aligning the studs with the rear of the catalytic converter.
Install the nuts securing the muffler to the catalytic converter, but DO NOT tighten at this time.
Apply a soapy solution to the following areas in order to ease the installation of the hangers. The
inner diameter of the exhaust pipe hanger
The exhaust pipe hanger rod
Press the exhaust pipe hangers over the exhaust pipe hanger rods.
Tighten
Tighten the muffler nuts by hand until each contacts the metal flange.
Tighten the muffler nuts to 45 N.m (33 lb ft).
On 6.0L and 8.1L equipped vehicles only, tighten the exhaust clamp to 50 N.m (36 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Customer Interest for Heat Shield: > 03-06-05-008D > Mar > 07 > Exhaust
System - Popping/Snapping Noise When Hot/Idling > Page 4338
Lower the vehicle.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Customer Interest for Heat Shield: > 03-06-05-008D > Mar > 07 > Exhaust
System - Popping/Snapping Noise When Hot/Idling > Page 4339
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Heat Shield: > 03-06-05-008D > Mar > 07 >
Exhaust System - Popping/Snapping Noise When Hot/Idling
Heat Shield: All Technical Service Bulletins Exhaust System - Popping/Snapping Noise When
Hot/Idling
Bulletin No.: 03-06-05-008D
Date: March 05, 2007
TECHNICAL
Subject: Exhaust Popping/Snapping Noise When Vehicle is Hot, at Idle, or Immediately After
Vehicle is Shut Off (Replace Muffler Heat Shield)
Models: 2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV
2002-2006 Chevrolet Avalanche, Suburban, Tahoe, Silverado, Silverado HD 2007 Chevrolet
Silverado Classic, Silverado HD Classic 2002-2006 GMC Sierra, Sierra HD , Yukon, Yukon Denali,
Yukon Denali XL 2007 GMC Sierra Classic, Sierra HD Classic 2003-2006 HUMMER H2
with 4.8L, 5.3L, 6.0L or 8.1L Gasoline Engine (VINs V, B, T, Z, N, V, G - RPOs LR4, L33, LM7,
L59, LQ9, LQ4, L18)
Supercede:
This bulletin is being revised to add the 2006 and 2007 (Classic Only) model years and the 5.3L
(L33) engine. Please discard Corporate Bulletin Number 03-06-05-008C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on a popping/snapping noise from underneath the vehicle at idle or
immediately after the vehicle is shut off. Some popping/snapping noise from the exhaust system
during cool down is a normal condition.
The noise may be intermittent depending on the outside temperature and or temperature of the
exhaust system at the time of testing.
Cause
As the exhaust system warms and cools, the muffler and the muffler heat shield expand and
contract at different rates and may cause a popping and/or snapping noise.
Some popping/snapping noise from the exhaust system during cool down is a normal condition.
The customer should be made aware that this service procedure is designed to reduce but not
eliminate all exhaust system popping and snapping during cool down.
Correction
Follow the service procedure below to correct this condition.
Some popping/snapping noise from the exhaust system during cool down is a normal condition.
The customer should be made aware that this service procedure is designed to reduce but not
eliminate all exhaust system popping and snapping during cool down.
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
In order to avoid being burned, do not service the exhaust system while it is still hot. Service the
system when it is cool.
Always wear protective goggles and gloves when removing exhaust parts as falling rust and sharp
edges could result in serious personal injury.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Heat Shield: > 03-06-05-008D > Mar > 07 >
Exhaust System - Popping/Snapping Noise When Hot/Idling > Page 4345
Remove the nuts securing the muffler to the catalytic converter.
On 6.0L and 8.1L equipped vehicles only, loosen the exhaust pipe clamp.
Do not use oil base lubricants on the rubber exhaust hangers.
Apply a soapy solution to the exhaust pipe hanger rods in order to ease the removal of the exhaust
hangers.
Pry the exhaust hangers free from the exhaust pipe hanger rods.
It is not necessary to remove the muffler from the vehicle to replace the muffler heat shield.
Reposition the muffler to gain access to the muffler heat shield.
Use extreme caution not to damage the muffler when removing the heat shield from the muffler.
Using an air-powered hack saw blade, or equivalent, cut off the existing muffler heat shield just as
the heat shield rises off of the muffler. See the illustration above.
Remove the heat shield from the muffler.
Hammer flush the remaining heat shield to the muffler.
The new heat shield should not come in contact with the remaining muffler heat shield. The new
heat shield should not come in contact with the horizontal lock seam on the muffler.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Heat Shield: > 03-06-05-008D > Mar > 07 >
Exhaust System - Popping/Snapping Noise When Hot/Idling > Page 4346
Install the new heat shield (see parts list below) onto the muffler as shown above.
Install three straps, P/N 10391259, so that the strap screw head will be located on top of the
muffler.
Tighten
Tighten the strap screw to 4 N.m (35 lb in).
Cut off the excess strap material and bend the strap over the strap screw head as indicated above.
Remove the exhaust pipe clamp.
ONLY 6.0L and 8.1L equipped vehicles require a new exhaust pipe clamp, P/N 15103174.
On 6.0L and 8.1L equipped vehicles only, install a new exhaust pipe clamp, P/N 15103174, on the
exhaust pipe.
Reposition the muffler in the correct position.
Slide the muffler forward into position, aligning the studs with the rear of the catalytic converter.
Install the nuts securing the muffler to the catalytic converter, but DO NOT tighten at this time.
Apply a soapy solution to the following areas in order to ease the installation of the hangers. The
inner diameter of the exhaust pipe hanger
The exhaust pipe hanger rod
Press the exhaust pipe hangers over the exhaust pipe hanger rods.
Tighten
Tighten the muffler nuts by hand until each contacts the metal flange.
Tighten the muffler nuts to 45 N.m (33 lb ft).
On 6.0L and 8.1L equipped vehicles only, tighten the exhaust clamp to 50 N.m (36 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Heat Shield: > 03-06-05-008D > Mar > 07 >
Exhaust System - Popping/Snapping Noise When Hot/Idling > Page 4347
Lower the vehicle.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Heat Shield: > 03-06-05-008D > Mar > 07 >
Exhaust System - Popping/Snapping Noise When Hot/Idling > Page 4348
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Technical Service Bulletins > Page 4349
Heat Shield: Specifications
Exhaust Heat Shield Bolt .....................................................................................................................
................................................... 9 Nm (80 inch lbs.) Exhaust Heat Shield Nut (Body Panel)
................................................................................................................................................... 9 Nm
(80 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel
Heat Shield: Service and Repair Exhaust Heat Shield Replacement Dash Panel
Exhaust Heat Shield Replacement Dash Panel
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Remove the engine shield bolts and shield, if necessary.
3. Remove the exhaust heat shield nuts. 4. Remove the exhaust heat shield (1, 3) from the dash
panel studs.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel > Page 4352
1. Install the exhaust heat shield (1, 3) to the dash panel studs.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the exhaust heat shield nuts.
- Tighten the nuts to 9 Nm (80 inch lbs.).
3. Install the engine shield and bolts, it necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel > Page 4353
Heat Shield: Service and Repair Floor Panel Heat Shield Replacement
Floor Panel Heat Shield Replacement
Removal Procedure
1. Remove the exhaust manifold pipe, if necessary. Refer to Exhaust Manifold Pipe Replacement
(6.OL, and 8.1L Engines). 2. Remove the catalytic converter, if necessary. Refer to Catalytic
Converter Replacement (4.8L and 5.3L Engines) or Catalytic Converter
Replacement (6.OL and 8.1. Engines)
3. Remove the exhaust front heat shield nuts. 4. Remove the exhaust front heat shield from the
studs.
5. If vehicle is a crew cab pick-up truck, remove the exhaust heat shield nuts. 6. Remove the
exhaust heat shield(s) from the studs.
7. If vehicle is a sport utility vehicle, remove the exhaust heat shield nuts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel > Page 4354
8. Remove the exhaust heat shield from the studs.
Installation Procedure
1. If vehicle is a sport utility vehicle, install the exhaust heat shield to the studs.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the exhaust heat shield nuts.
- Tighten the nuts to 9 Nm (80 inch lbs.).
3. If the vehicle is a crew cab pick-up truck, install the exhaust heat shield(s) to the studs. 4. Install
the exhaust heat shield nuts.
- Tighten the nuts to 9 Nm (80 inch lbs.).
5. Install the exhaust front heat shield to the studs. 6. Install the exhaust front heat shield nuts,
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel > Page 4355
- Tighten the nuts to 9 Nm (80 inch lbs.).
7. Install the catalytic converter, if necessary. Refer to Catalytic Converter Replacement (4.8L and
5.3L Engines) or Catalytic Converter Replacement
(6.OL and 8.1L Engines).
8. Install the exhaust manifold pipe, if necessary. Refer to Exhaust Manifold Pipe Replacement
(6.OL, and 8.1. Engines).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Heat Shield, Exhaust > Component
Information > Service and Repair > Exhaust Heat Shield Replacement Dash Panel > Page 4356
Heat Shield: Service and Repair Exhaust Heat Shield Replacement
Exhaust Heat Shield Replacement
Removal Procedure
1. Remove the exhaust muffler. Refer to Muffler Replacement (4.8L and 5.3L Engines) or Muffler
Replacement (6.OL and 8.1. Engines). 2. It equipped with a short bed, remove the exhaust heat
shield bolts. 3. Remove the exhaust heat shield.
Installation Procedure
1. If equipped with a short bed, install the exhaust heat shield.
Notice: Refer to Fastener Notice in Cautions and Notices.
2. Install the exhaust heat shield bolts.
- Tighten the bolts to 9 Nm (80 inch lbs.).
3. Install the exhaust muffler. Refer to Muffler Replacement (4.8L and 5.3L Engines) or Muffler
Replacement (6.OL and 8.1L Engines).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Muffler > Component Information >
Specifications
Muffler: Specifications
Exhaust Muffler Clamp Bolt .................................................................................................................
.................................................... 30 Nm (22 ft. lbs.) Exhaust Muffler Nut ..........................................
....................................................................................................................................... 40 Nm (30 ft.
lbs.) Exhaust Pipe Clamp ....................................................................................................................
.............................................................. 40 Nm (30 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Muffler > Component Information >
Specifications > Page 4360
Muffler: Service and Repair
Muffler Replacement (4.81- and 5.31- Engines)
- Tools Required J 38185 Hose Clamp Pliers
Removal Procedure
1. Remove the rear tires and wheels. Refer to Tire and Wheel Removal and Installation in Tires
and Wheels. 2. Remove the oil pan skid plate bolts and plate, if necessary. 3. Remove the spare
tire.
4. If servicing a vehicle equipped with regular production option (RPO) Z55, disconnect the chassis
harness from the following electrical connectors:
- Electronic suspension rear position sensor (1)
- Rear shock (2)
Important: Do not attempt to pry the rear suspension sensor link rod from the rear position sensor
ball stud. 5. Remove the left and right sensor link rods from the sensors, perform the following:
5.1. Support the sensor lever with your hand
5.2. Twist the link rod in order to remove it from the ball stud
6. Install adjustable jack stands under the rear axle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Muffler > Component Information >
Specifications > Page 4361
7. Remove the rear axle vent hose from the rear axle, if necessary. 8. Remove the vent hose
swivel clip from the rear brake crossover pipe.
9. Remove the rear shock absorbers lower bolts and nuts.
10. Lower the rear axle slightly, using the adjustable jack stands, in order to remove the muffler.
11. Remove the exhaust muffler nuts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Muffler > Component Information >
Specifications > Page 4362
12. Remove the muffler from the insulators.
Installation Procedure
1. Apply lubricant to the exhaust insulators in order to aid in installation. 2. Install the muffler to the
insulators.
Notice: Refer to Fastener Notice in Cautions and Notices.
3. Install the exhaust muffler nuts.
- Tighten the nuts to 40 Nm (30 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Muffler > Component Information >
Specifications > Page 4363
4. Raise the rear axle, using the adjustable jackstands. 5. Install the lower bolts and nuts to the rear
shock absorbers.
- Tighten the rear bolts to 95 Nm (70 ft. lbs.).
6. Remove the adjustable jack stands from under the rear axle.
7. Install the vent hose swivel clip to the rear brake crossover pipe. 8. Install the rear axle vent hose
to the rear axle, if necessary.
9. If servicing a vehicle, equipped with RPO Z55, install the left and right sensor link rods to the
sensors. Using J 38185 install the link rods to the
ball studs on the sensor levers.
10. Connect the chassis harness to the following electrical connectors:
- Electronic suspension rear position sensor (1)
- Rear shock (2)
11. Install the spare tire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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12. Install the oil pan skid plate and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
13. Install the rear tires and wheels. Refer to Tire and Wheel Removal and Installation in Tires and
Wheels.
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Chevrolet Workshop Manuals > Engine, Cooling and Exhaust > Exhaust System > Seals and Gaskets, Exhaust > Exhaust
Manifold Gasket > Component Information > Service and Repair
Exhaust Manifold Gasket: Service and Repair
Exhaust Seal Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Remove the engine shield bolts and shield, if necessary.
3. Remove the oil pan skid plate bolts and plate, if necessary.
4. Disconnect the CPA retainer. 5. Disconnect the oxygen sensor electrical connector (1). 6.
Support the catalytic converter or exhaust manifold pipe with adjustable jackstands.
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7. Remove the right exhaust manifold pipe nuts.
8. Remove the left exhaust manifold pipe nuts. 9. Remove the exhaust hanger mounting bracket
bolts.
10. Lower the catalytic converter or exhaust manifold pipe using the adjustable jackstands. 11.
Remove the exhaust manifold pipe seal(s).
Installation Procedure
1. Install the exhaust manifold pipe seal(s). 2. Raise the catalytic converter or exhaust manifold
pipe using the adjustable jackstands. 3. Install the exhaust hanger mounting bracket bolts.
Notice: Refer to Fastener Notice in Cautions and Notices.
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4. Install the left exhaust manifold pipe nuts.
- Tighten the transmission bolts to 100 Nm (74 ft. lbs.).
- Tighten the exhaust pipe hanger bracket bolts to 12 Nm (106 inch lbs.).
- Tighten the exhaust manifold pipe nuts to 50 Nm (39 ft. lbs.).
5. Install the right exhaust manifold pipe nuts.
- Tighten the nuts to 50 Nm (39 ft. lbs.).
6. Connect the oxygen sensor electrical connector (1). 7. Connect the CPA retainer. 8. Remove the
adjustable jackstands from catalytic converter or exhaust manifold pipe.
9. Install the oil pan skid plate and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
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10. Install the engine shield and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
11. Lower the vehicle.
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Modules - Computers and Control Systems > Body Control Module > Component Information > Locations
Locations View
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Body Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Information and Instructions > Page 4381
Electrical Symbols Part 2
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Electrical Symbols Part 3
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Information and Instructions > Page 4383
Electrical Symbols Part 4
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Body Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 4406
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4407
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4408
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4409
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4410
Body Control Module: Connector Views
Body Control Module Connector (BCM) - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4411
Body Control Module (BCM) - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4412
Body Control Module (BCM) - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4413
Body Control Module: Electrical Diagrams
Controlled/Monitored Subsystem References
Controlled/Monitored Subsystem References
Body Control Module Schematics: Controlled/Monitored Subsystem References
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4414
Exterior Lighting Systems References
Exterior Lighting Systems References
Body Control Module Schematics: Exterior Lighting Systems References
Interior Lighting Systems References
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4415
Interior Lighting Systems References
Body Control Module Schematics: Interior Lighting Systems References
Power, Ground and Serial Data
Power, Ground and Serial Data
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4416
Body Control Module Schematics: Power, Ground And Serial Data
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures
Body Control Module: Procedures
IMPORTANT: If any module is replaced, programming the module with the proper RPO
configurations must be done prior to performing the Passlock Learn procedure.
1. The BCM must be programmed with the proper RPO configurations. The BCM stores the
information regarding the vehicle options. If the BCM is
not properly configured with the correct RPO codes the BCM will not control the features properly.
Ensure that the following conditions exist in order to prepare for BCM programming: ^
The battery is fully charged.
^ The ignition switch is in the RUN position.
^ The DLC is accessible.
^ All disconnected modules and devices are reconnected before programming.
2. Follow the SPS instructions on the Techline Terminal and scan tool to program the BCM. 3. If
the BCM fails to accept the program, perform the following steps:
^ Inspect all BCM connections.
^ Verify that the SPS Techline Terminal and scan tool have the latest software version.
Passlock Learn Procedures Refer to the Theft Deterrent sub-system for the appropriate learn
procedure.
IMPORTANT: After programming, perform the following to avoid future misdiagnosis: 1. Turn the
ignition OFF for 10 seconds. 2. Connect the scan tool to the data link connector. 3. Turn the ignition
ON with the engine OFF. 4. Use the scan tool in order to retrieve History DTCs from all modules. 5.
Clear all history DTCs.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures > Page 4419
Body Control Module: Removal and Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
1. Disconnect the negative battery cable(s). 2. Remove the knee bolster.
3. Disconnect the brown connector. 4. Disconnect all other connectors (1). 5. Remove the BCM
from the sliding bracket.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Body Control Module > Component Information > Service and Repair >
Procedures > Page 4420
1. Slide the BCM onto the bracket. 2. Connect all the connectors (1) except the brown connector. 3.
Connect the brown connector.
4. Install the knee bolster. 5. Connect the negative battery cable(s). 6. Reprogram the BCM.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations
Electronic Throttle Control Module: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 4424
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 4425
Electronic Throttle Control Module: Diagrams
Throttle Actuator Control (TAC) Module Connector C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 4426
Throttle Actuator Control (TAC) Module Connector C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 4427
Electronic Throttle Control Module: Description and Operation
THROTTLE ACTUATOR CONTROL (TAC) MODULE
Throttle Actuator Control (TAC) Module
The TAC module is the control center for the electronic throttle system. The TAC module and the
powertrain control module (PCM) communicate via a dedicated redundant serial data circuit. The
TAC module and the PCM monitor the commanded throttle position and compare the commanded
position to the actual throttle position. This is accomplished by monitoring the APP and the TP
sensor. These 2 values must be within a calibrated value of each other. The TAC module also
monitors each individual circuit of the TP sensor and the APP to verify proper operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations >
Page 4428
Electronic Throttle Control Module: Service and Repair
THROTTLE ACTUATOR CONTROL (TAC) MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Release the retainer tab from the left side of the throttle actuator control (TAC) module. 2. Slowly
slide the TAC module out of the retaining bracket. 3. Disconnect the TAC module connectors from
the TAC module.
INSTALLATION PROCEDURE
1. Connect the TAC module connectors to the TAC module. 2. Slide the TAC module into the TAC
module bracket. 3. Push the TAC module towards the bracket in order to snap the TAC module into
the bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Engine Control Module: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set > Page
4437
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage > Page 4443
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set
Engine Control Module: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire
DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set > Page 4448
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > All Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls Aftermarket Accessory Usage > Page 4454
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Technical Service
Bulletins > Page 4455
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions
Engine Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4458
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4459
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram
Information and Instructions > Page 4460
Electrical Symbols Part 3
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Electrical Symbols Part 4
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Engine Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Engine Control Module: Connector Views
Powertrain Control Module (PCM) C1 Part 1
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Powertrain Control Module (PCM) C1 Part 2
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Powertrain Control Module (PCM) C1 Part 3
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Powertrain Control Module (PCM) C2 Part 1
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Powertrain Control Module (PCM) C2 Part 2
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Powertrain Control Module (PCM) C2 Part 3
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> Electronic Ignition (EI) System Description
Engine Control Module: Description and Operation Electronic Ignition (EI) System Description
POWERTRAIN CONTROL MODULE (PCM)
The PCM controls all ignition system functions, and constantly corrects the basic spark timing. The
PCM monitors information from various sensor inputs that include the following:
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Mass Airflow (MAF) sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Vehicle Speed Sensor (VSS)
^ The transmission gear position or range information sensors
^ The Engine Knock Sensors (KS)
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Engine Control Module: Description and Operation Powertrain Control Module (PCM) Description
General Information
The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while
maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ The fuel control
^ The Ignition Control (IC)
^ The Knock Sensor (KS) system
^ The automatic transmission shift functions
^ The manual transmission
^ The cruise control enable, if equipped
^ The generator
^ The evaporative emissions (EVAP) purge
^ The A/C clutch control, if equipped
^ The secondary air injection (AIR), if equipped
^ The Exhaust Gas Recirculation (EGR)
PCM Function
The PCM supplies a buffered voltage to various sensors and switches. The PCM controls most
components with electronic switches which complete a ground circuit when turned ON.
Powertrain Control Module
Powertrain Control Module
The Powertrain Control Module (PCM) is located in the engine compartment. The PCM is the
control center of the vehicle. The PCM controls the following:
^ The fuel metering system
^ The transmission shifting
^ The ignition timing
^ The on-board diagnostics for powertrain functions
The PCM constantly monitors the information from various sensors and controls the systems that
affect vehicle performance and emissions. The PCM also performs the diagnostic functions for
those systems. The PCM can recognize operational problems and alert the driver through the
Malfunction Indicator Lamp (MIL) when a malfunction has occurred. When a malfunction is
detected, the PCM stores a Diagnostic Trouble Code (DTC) which helps to identify problem areas.
This is done to aid the technician in making repairs.
The PCM supplies either 5.0 or 12.0 volts to power various sensors and switches. This is done
through resistances in the PCM. The resistance is so high in value that a test lamp does not
illuminate when connected to the circuit. In some cases, even an ordinary shop voltmeter does not
give an accurate reading because the voltmeters resistance is too low. Therefore, a DMM with a
minimum of 10 megaohms input impedance is required to ensure accurate voltage readings.
The PCM controls output circuits such as the fuel injectors, the Idle Air Control (IAC), the cooling
fan relays, etc. by controlling the ground or the power feed circuit through transistors or a device
called an output driver module.
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Torque Management
Torque management is a function of the PCM that reduces engine power under certain conditions.
Torque management is performed for the following reasons:
1. To prevent over-stressing the powertrain and driveline components 2. To prevent damage to the
vehicle during certain abusive maneuvers 3. To reduce engine speed when the IAC is out of the
normal operating range
The PCM monitors the following sensors and engine parameters in order to calculate engine output
torque:
^ The air/fuel ratio
^ The Mass Air Flow (MAF) sensor
^ The Manifold Absolute Pressure (MAP) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The spark advance
^ The engine speed
^ The Engine Coolant Temperature (ECT) Sensor
^ The A/C clutch status
The PCM monitors the torque converter status, the transmission gear ratio, and the engine speed
in order to determine if torque reduction is required. The PCM retards the spark as appropriate to
reduce engine torque output if torque reduction is required. The PCM also shuts OFF the fuel to
certain injectors in order to reduce the engine power in the case of an abusive maneuver.
The following are instances when engine power reduction is likely to be experienced:
^ During transmission upshifts and downshifts
^ During heavy acceleration from a standing start
^ When the clutch pedal is released too quick under a heavy load, 6.0L only
^ When one set of drive axles looses traction while the other set of drive axles are not moving, 4
Wheel Drive only and in 4WD low
^ If the IAC is out of the normal operating range, except 6.0L
^ When the driver is performing harsh or abusive maneuvers such as shifting into gear at high
throttle angles or shifting the transmission from reverse to drive to create a rocking motion
The driver is unlikely to notice the torque management actions in the first 2 instances. The engine
power output is moderate at full throttle in the other cases.
The PCM calculates the amount of spark retard necessary to reduce the engine power by the
desired amount. The PCM disables the fuel injectors for cylinders 1, 4, 6, and 7 in the case of an
abusive maneuver.
Basic Knowledge Required
Without a basic knowledge of electricity, you will have difficulty using the diagnostic procedures.
You should understand the basic theory of electricity and know the meaning of voltage-volts,
current-amps, and resistance-ohms. You should understand what happens in a circuit with an open
or a shorted wire. You should be able to read and understand a wiring diagram.
PCM Service Precautions
The PCM is designed to withstand normal current draws associated with vehicle operations. Avoid
overloading any circuit. When testing for opens or shorts, do not ground any of the PCM circuits
unless instructed. When testing for opens or shorts, do not apply voltage to any of the PCM circuits
unless instructed. Only test these circuits with a DMM while the PCM connectors remain
connected.
Engine Controls Information
The driveability and emissions information describes the function and operation of the powertrain
control module (PCM).
The engine controls Information contains the following:
^ Component locations
^ Wiring diagrams
^ PCM terminal end view and terminal definitions
^ Diagnostic System Check-Computers and Controls Systems
^ Diagnostic trouble code (DTC) tables
The component system includes the following items:
^ Component and circuit description
^ On-vehicle service for each sub-system
^ Functional checks and diagnostic tables
The DTCs also contain diagnostic support information containing circuit diagrams, circuit or system
information, and helpful diagnostic information.
System Status and Drive Cycle For Inspection/Maintenance
The System Status selection is included in the scan tool System Info menu.
Several states require that the I/M (OBD II system) pass on-board tests for the major diagnostics
prior to having a vehicle emission inspection. This is
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also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the System Status, complete or not complete, in
order to verify that the vehicle meets the criteria to comply with local area requirements. Using the
System Status display, any of the following systems or combination of systems may be monitored
for I/M Readiness:
^ The catalyst
^ The Evaporative Emission (EVAP) system
^ The Heated Oxygen Sensors (HO2S)
^ The HO2S heater
^ The Exhaust Gas Recirculation (EGR) system
^ The secondary air injection (AIR) system
IMPORTANT: The System Status display indicates only whether or not the test has been
completed. The System Status display does not necessarily mean that the test has passed. If a
Failed Last Test indication is present for a DTC associated with one of the above systems,
diagnosis and repair is necessary in order to meet the I/M requirement. Verify that the vehicle
passes all of the diagnostic tests associated with the displayed System Status prior to returning the
vehicle to the customer. Refer to the Typical Drive Cycle table, more than one drive cycle may be
needed, to use as a guide to complete the I/M System Status tests.
Typical Drive Cycle
Following a DTC info clear, System Status clears for one or all of these systems. Following a
battery disconnect or a PCM replacement, all System Status information clears.
Primary System Based Diagnostics
There are primary system-based diagnostics which evaluate the system operation and their effect
on vehicle emissions. The primary system-based diagnostics are listed below, with a brief
description of the diagnostic functionality.
Oxygen Sensor Diagnosis
Diagnose the fuel control heated oxygen sensors (HO2S) for the following conditions:
^ Heater performance, heater current monitor
^ Response switches, number or switches R/L or L/R
^ Response time, time to switch R/L or L/R
^ Inactive signal, output steady at bias voltage - approximately 450 mV
^ Signal fixed high
^ Signal fixed low
Diagnose the catalyst monitor HO2S for the following functions:
^ Heater performance, heater current monitor
^ Signal fixed low
^ Signal fixed high
^ Inactive sensor
Heated Oxygen Sensors
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases.
The PCM uses the signal voltage from the fuel control HO2S in a Closed Loop in order to adjust
the fuel injector pulse width. While in a Closed Loop, the PCM can adjust fuel delivery in order to
maintain an air to fuel ratio which allows the best combination of emission control and driveability.
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If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Catalyst Monitor Heated Oxygen Sensors
In order to control emissions of HydroCarbons (HC), Carbon Monoxide (CO), and Oxides Of
Nitrogen (NOx), the system uses a TWC. The catalyst promotes a chemical reaction which oxidizes
the HC and CO present in the exhaust gas, converting the HC and CO into harmless water vapor
and carbon dioxide. The catalyst also converts NOx to nitrogen. Catalyst monitor HO2S,
post-catalyst HO2S, are always located downstream of the catalytic converter.
The PCM has the ability to monitor this process using the post catalyst HO2S. The pre-sensors
produce an output signal which indicates the amount of oxygen present in the exhaust gas entering
the TWC. The post sensor produces an output signal which indicates the oxygen storage capacity
of the catalyst. This in turn indicates the catalysts ability to convert exhaust gases efficiently. If the
catalyst is operating efficiently, the pre-HO2S signal is far more active than that produced by the
post-HO2S.
In addition to catalyst monitoring, the post-HO2S has a limited role in controlling fuel delivery. If the
post-HO2S signal indicates a high or low oxygen content for an extended period of time while in a
Closed Loop, the PCM adjusts the fuel delivery slightly in order to compensate.
Catalyst Monitor Diagnostic Operation
The catalyst monitor diagnostic measures oxygen storage capacity of the catalyst converter. In
order to do this, the HO2S are installed before and after the TWC. Voltage variations between the
sensors allow the PCM to determine the catalyst emission performance.
As a catalyst becomes less effective in promoting chemical reactions, the catalysts capacity to
store and release oxygen generally degrades. The catalyst monitor diagnostic is based on a
correlation between conversion efficiency and oxygen storage capacity.
A good catalyst, e.g. 95 percent hydrocarbon conversion efficiency, shows a relatively flat output
voltage on the post-catalyst HO2S. A degraded catalyst, 65 percent hydrocarbon conversion,
shows a greatly increased activity in output voltage from the post catalyst HO2S.
The post-catalyst HO2S is used to measure the oxygen storage and release capacity of the
catalyst. A high oxygen storage capacity indicates a good catalyst. Low oxygen storage capacity
indicates a failing catalyst. The TWC and the HO2S must be at operating temperature in order to
achieve correct oxygen sensor voltages like those shown in the post-catalyst HO2S outputs
graphic.
The catalyst monitor diagnostic is sensitive to the following conditions:
^ Exhaust leaks
^ HO2S contamination
^ Alternative fuels
Exhaust system leaks may cause the following:
^ Prevent a degraded catalyst from failing the diagnostic
^ Cause a false failure for a normally functioning catalyst
^ Prevent the diagnostic from running
Some of the contaminants that may be encountered are phosphorus, lead, silica, and sulfur. The
presence of these contaminants prevent the TWC diagnostic from functioning properly.
Three-Way Catalyst Oxygen Storage Capacity
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Three-Way Catalyst Oxygen Storage Capacity
The PCM must monitor the TWC system for efficiency. In order to accomplish this, the PCM
monitors the pre-catalyst and post-catalyst HO2S. When the TWC is operating properly, the
post-catalyst (2) HO2S shows significantly less activity than the pre-catalyst (1) HO2S. The TWC
stores oxygen during the normal reduction and oxidation process. The TWC releases oxygen
during the normal reduction and oxidation process. The PCM calculates the oxygen storage
capacity using the difference between the pre-catalyst and post-catalyst HO2S voltage levels.
Whenever the sensor activity of the post-catalyst (2) HO2S nears the sensor activity of the
pre-catalyst (1) HO2S, the catalysts efficiency is degraded. Aftermarket HO2S characteristics may
be different from the original equipment manufacturer sensor. This may lead to a false pass or a
false fail of the catalyst monitor diagnostic. Similarly, if an aftermarket catalyst does not contain the
same amount of precious metal content as the original part, the correlation between oxygen
storage and conversion efficiency may be altered enough to set a false DTC.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft rotational velocity, aka reference period,
variations. The PCM determines crankshaft rotational velocity using the Crankshaft Position (CKP)
Sensor and Camshaft Position (CMP) Sensor. When a cylinder misfires, the crankshaft slows down
momentarily. By monitoring the crankshaft and CMP sensor signals, the PCM can calculate when a
misfire occurs.
For a non-catalyst damaging misfire, the diagnostic is required to monitor a misfire present for
between 1,000-3,200 engine revolutions.
For catalyst damage misfire, the diagnostic responds to the misfire within 200 engine revolutions
Rough roads may cause false misfire detection. A rough road applies sudden torque variations to
the drive wheels and drivetrain. This torque can intermittently decrease the crankshaft rotational
velocity. The Antilock Braking (ABS) System detects uneven speed between the vehicles wheels
and sends data via the serial data bus to the PCM to disable the misfire monitor until the rough
road is no longer detected.
On automatic transmission equipped vehicles, the Torque Converter Clutch (TCC) disables
whenever a misfire is detected. Disabling the TCC isolates the engine from the rest of the drive line
and minimizes the affect of the drive wheel inputs on crankshaft rotation.
When the TCC has disabled as a result of misfire detection, the TCC is re-enabled after
approximately 3,200 engine revolutions if no misfire is detected. The TCC remains disabled
whenever the misfire is detected, with or without a DTC set. This allows the misfire diagnostic to
reevaluate the system.
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Whenever a cylinder misfires, the misfire diagnostic counts the misfire and notes the crankshaft
position at the time the misfire occurred.
A current and a history misfire counter is maintained for each cylinder. The misfire current
counters, Misfire Cur #1-8, indicate the number of firing events out of the last 200 cylinder firing
events which were misfires. The misfire current counters displays real time data without a misfire
DTC stored. The misfire history counters, Misfire Hist #1-8, indicate the total number of cylinder
firing events which were misfires. The misfire history counters display 0 until the misfire diagnostic
has failed and a DTC P0300 is set. Once the misfire DTC sets, the misfire history counters will be
updated every 200 cylinder firing events. The Misfire counters graphic illustrates how these misfire
counters are maintained.
When crankshaft rotation is erratic, the PCM detects a misfire condition. Because of this erratic
condition, the data that is collected by the diagnostic can sometimes incorrectly identify which
cylinder is misfiring. The Misfire Counters graphic shows there are misfires counted from more than
one cylinder. Cylinder #1 has the majority of counted misfires. In this case, the misfire counters
would identify cylinder #1 as the misfiring cylinder. The misfires in the other counters were just
background noise caused by the erratic rotation of the crankshaft. If the number of accumulated
misfires is sufficient for the diagnostic to identify a true misfire, the diagnostic will set DTC
P0300-Misfire Detected. The illustration depicts an accumulation in the history buffers.
If two cylinders in sequential tiring order are both misfiring, the first misfiring cylinder will
accumulate misfires in the cylinder buffer, but the second misfiring cylinder will not. This is because
the PCM compares a misfiring cylinder with the cylinder 90 degrees prior to that cylinder in the
firing order. Therefore the PCM would be comparing crankshaft speed of the second misfiring
cylinder to an already suspect cylinder. The PCM however, will be able to detect both misfiring
cylinders after the engine exceeds 2,000 RPM. This is because the PCM then starts to compare
misfires to the opposing cylinder rather than the previous cylinder in the firing order.
Use Techline equipment to monitor the misfire counter data on applicable vehicles. Knowing which
specific cylinders misfire can lead to the root cause. Using the information in the misfire counters
identifies which cylinders are misfiring. If the counters indicate cylinders number 1 and 4 misfired,
look for a circuit or component common to both cylinders.
The misfire diagnostic may indicate a fault due to a temporary fault not necessarily caused by a
vehicle emission system malfunction. Examples include the following items:
^ Contaminated fuel
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^ Running out of fuel
^ Fuel fouled spark plugs
^ Basic engine fault
Fuel Trim System Operation
The fuel trim system monitors the averages of short-term and long-term fuel trim values. If these
fuel trim values stay at the individual limits for a calibrated period of time, a malfunction is indicated.
The fuel trim diagnostic compares the average of short and long-term fuel trim values. If either
value is within the thresholds, a pass is recorded. If either value is outside the thresholds, a rich or
lean fuel trim DTC will set.
Comprehensive Component Monitor Diagnostic
Comprehensive component monitoring diagnostics are required to monitor emissions-related input
and output powertrain components.
Input Components The PCM monitors the input components for circuit continuity and out-of-range
values. This includes performance checking. Performance checking refers to indicating a fault
when the signal from a sensor does not seem reasonable, such as a Throttle Position (TP) sensor
that indicates high throttle position at low engine loads or manifold Absolute Pressure (MAP)
Voltage. The input components may include, but are not limited to, the following sensors: ^
The Vehicle Speed (VSS) Sensor
^ The Mass Air Flow (MAF) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Crankshaft Position (CKP) Sensor
^ The Knock Sensor (KS)
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Camshaft Position (CMP) Sensor
^ The Manifold Absolute Pressure (MAP) Sensor
In addition to the circuit continuity and rationality check, the engine coolant temperature (ECT)
sensor is monitored for the sensors ability to achieve a steady state temperature to enable Closed
Loop fuel control.
Output Components Diagnose the output components for the proper response to PCM commands.
Components where functional monitoring is not feasible will be monitored for circuit continuity and
out-of-range values if applicable.
Output components to be monitored include, but are not limited to, the following circuits: ^
The Idle Air Control (IAC) Motor
^ The Evaporative Emission (EVAP) System
^ The electronic transmission controls
^ The A/C relay, if equipped
^ The VSS output
^ The Malfunction Indicator Lamp (MIL) Control
^ The cruise control enable, if equipped
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Powertrain Control Module (PCM) Programming (Off-board)
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(Off-board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: ^
DO NOT program a control module unless you are directed by a service procedure or you are
directed by a General Motors Corporation service bulletin. Programming a control module at any
other time will not permanently correct a customer's concern.
^ The Off-Board Programming is used in situations where a control module must be programmed
without having the vehicle present. The Off-Board Programming Adapter must be used to perform
the Off-Board Programming procedure. The adapter allows the control module to power up and
allows the Tech 2 to communicate with the control module.
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
Ensure that all connections are secure at the following locations: ^
The Off-Board Programming Adapter
^ The Tech 2
^ The control module
^ The Techline terminal
OFF-BOARD PROGRAMMING
1. Obtain the VIN of the vehicle for which the control module is being programmed. 2. With the
Techline terminal, select Service Programming. 3. Select Tech 2, Reprogram ECU, and Off-Board
Programming Adapter as the ECU location. 4. Connect the control module, Off-Board
Programming Adapter, and the Tech 2 as described on the Techline terminal. Ensure you use the
correct
harness connector from the Off-Board Programming Adapter kit.
5. With the Tech 2, select Service Programming Request Information function. The Tech 2
communicates with the control module and receives the
access code.
6. With the Tech 2, exit the Service Programming Request Information. 7. Disconnect the Tech 2
from the Off-Board Programming Adapter. 8. Connect the Tech 2 to the Techline terminal. 9. Turn
ON the Tech 2.
10. With the Techline terminal, enter the VIN of the vehicle that will be receiving the control module.
11. The Techline terminal will display the message, attaching to database. 12. Identify what type of
programming that you are performing. 13. Select the appropriate calibration file. 14. Ensure all
connections are secure. 15. The Techline terminal displays a summary screen that summarizes
your selections. After confirming you choices, the Techline terminal
automatically loads the calibration files to the Tech 2.
16. After the download is complete, turn OFF the Tech 2. 17. Disconnect the Tech 2 from the
Techline terminal. 18. Connect the Tech 2 to the Off-Board Programming Adapter. 19. With the
Tech 2, select Service Programming.
IMPORTANT: DO NOT turn OFF the Off-Board Programming Adapter if the programming
procedure is interrupted or unsuccessful. Ensure the control module and the Off-Board
Programming Adapter connections are secure and the Techline operating software is up to date.
Attempt to reprogram the control module. If the control module cannot be programmed, replace the
control module.
20. With the Tech 2, select Program. 21. After the download is complete, exit Service
Programming. 22. Turn OFF the Off-Board Programming Adapter.
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Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(On-Board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: DO NOT program a control module unless you are directed by a service procedure
or you are directed by a General Motors Corporation service bulletin. Programming a control
module at any other time will not permanently correct a customers concern.
Ensure the following conditions are met before programming a control module: ^
Vehicle system voltage There is no charging system concern. All charging system concerns must be repaired before
programming a control module.
- Battery voltage is greater than 12 volts but less than 16 volts. The battery must be charged before
programming the control module if the battery voltage is low.
- A battery charger is NOT connected to the vehicle's battery. Incorrect system voltage or voltage
fluctuations from a battery charger, may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicle's battery. ^
Twilight sentinel
^ Interior lights
^ Daytime running lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system. Refer to the Owners manual.
^ HVAC systems
^ Cooling System fans, etc.
^ The ignition is in the proper position. The scan tool prompts you to turn ON the ignition, with the
engine OFF. DO NOT change the position of the ignition switch during the programming procedure,
unless instructed to do so.
^ All tool connections are secure. RS-232
- The connection at the DLC is secure.
- Voltage supply circuits
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
REMOTE PROGRAMMING
1. Turn OFF the ignition. 2. Install the Tech 2 to the data link connector (DLC). 3. Turn ON the
ignition, with the engine OFF. 4. Turn OFF all vehicle accessories. 5. With the Tech 2, select
Service Programming. 6. Identify vehicle information as requested by the Tech 2. 7. Select the type
of module you are programming. 8. Select the type of programming to be performed. 9. Verify the
displayed VIN with the vehicle VIN. If the displayed VIN does not match the actual VIN, write down
the actual VIN and correct the
VIN at the Techline terminal.
10. When complete, Exit Service Programming. 11. Turn OFF the Tech 2 and disconnect the Tech
2 from the vehicle. 12. Turn OFF the ignition. 13. Connect the Tech 2 to the Techline terminal. 14.
Select Service Programming. 15. Select Tech 2 as the tool you are using. 16. Select the type of
programming to be performed. 17. Verify the displayed VIN with the vehicle VIN. Correct the VIN
as necessary. 18. Select the type of module you are programming. 19. Identify what type of
programming that you are performing.
^ Normal-This type of programming is for updating an existing calibration or programming a new
controller.
^ Vehicle configuration index (VCI)-This selection is used if the vehicle VIN is unavailable or not
recognized by the Techline terminal. Observe, you will need to contact the Techline Customer
Support center to use this option.
^ Reconfigure-This is to reconfigure a vehicle, such as tire size and axle ratio changes.
20. Select the appropriate calibration file. 21. Ensure all connections are secure. 22. Select Reprog
to initiate the download of the new calibration to the Tech 2. 23. After the download is complete,
turn OFF the Tech 2. 24. Disconnect the Tech 2 from the Techline terminal. 25. Install the Tech 2
to the data link connector (DLC). 26. Turn ON the Tech 2. 27. Turn ON the ignition, with the engine
OFF. 28. Select Service Programming.
IMPORTANT: DO NOT turn OFF the ignition if the programming procedure is interrupted or
unsuccessful. Ensure that all the PCM and DLC
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connections are secure and the Techline(TM) operating software is up to date. Attempt to
reprogram the control module. If the control module cannot be programmed, replace the control
module. Refer to Powertrain Control Module (PCM) Replacement.
29. Select Program. 30. After the download is complete, EXIT Service Programming. 31. Turn OFF
the ignition for 30 seconds. 32. Turn OFF the Tech 2. 33. If a control module is replaced the
following service procedures must be performed:
^ CKP System Variation Learn Procedure
^ Inspection/Maintenance (I/M) Complete System Set Procedure
^ Programming Theft Deterrent System Components
PROGRAMMING VERIFICATION
1. With a scan tool, clear the DTCs. 2. Attempt to start the engine. 3. Repeat the Service
Programming procedure if the engine does not start or operates poorly. Perform the following
procedures before programming
the PCM: ^
Ensure the control module and DLC connections are OK.
^ Ensure the Techline operating software is up to date.
^ Ensure the calibration part number is correct for the vehicle.
4. Attempt to program the control module. If the control module still cannot be programmed
properly, replace the control module. Refer to
Powertrain Control Module (PCM) Replacement. You must program the replacement control
module.
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Engine Control Module: Service and Repair Powertrain Control Module (PCM) Replacement
Service of the powertrain control module (PCM) should normally consist of either replacement of
the PCM or electrically erasable programmable read only memory (EEPROM) programming. If the
diagnostic procedures call for the PCM to be replaced, the PCM should be inspected first to see if
the correct part is being used. If the correct part is being used, remove the faulty PCM and install
the new service PCM.
IMPORTANT: To prevent internal PCM damage, the ignition must be OFF when disconnecting or
reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail,
PCM fuse, or jumper cables. ^
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM
module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are
installed correctly. The gaskets prevent contaminant intrusion into the PCM.
^ The replacement PCM must be programmed
Removal Procedure
1. Release the PCM cover mounting holes (1,5) away from the mounting tabs on the PCM
mounting bracket. 2. Release the PCM cover (8) from the mounting bracket. 3. Remove the PCM
cover.
NOTE: ^
Refer to PCM and ESD Notice in Service Precautions.
^ In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or
reconnecting the PCM connector.
4. Disconnect the PCM harness connectors (6). 5. Release the spring latch (2) from the PCM. 6.
Release the PCM mounting tabs (3) from the PCM. 7. Remove the PCM (4) from the engine
compartment.
Installation Procedure
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1. Install the PCM (4) to the PCM mounting bracket (7) ensuring that the mounting tabs (3) are
engaged. 2. Secure the spring latch (2) to the PCM.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Connect the PCM connectors (6) to the PCM (4).
Tighten Tighten the PCM connector end fasteners to 8 N.m (71 lb in).
4. Install the PCM cover (8) to the PCM mounting bracket (7), ensuring the mounting tabs on the
PCM mounting bracket are engaged into the
mounting holes in the PCM cover.
5. If a new PCM is being installed, program the PCM. See: Testing and Inspection/Programming
and Relearning
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Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
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Powertrain Control Module (PCM) Programming (Off-board) > Page 4509
Engine Control Module: Service and Repair Service Programming System (SPS)
The Service Programming System (SPS) allows a technician to program a control module through
the Data Link Connector (DLC). The information transfer circuit that is used at the DLC is the same
serial data circuit used by the scan tool for retrieving Diagnostic Trouble Codes (DTCs), displaying
data, clearing DTCs, etc. This procedure offers the ability to install software/calibrations matched to
a particular vehicle.
Most control modules have 2 types of memory. The software/calibrations reside in the flash
memory. The two types of memory are listed below:
^ Electrically Erasable Programmable Read Only Memory (EEPROM)
This type of memory allows selected portions of memory to be programmed while other portions
remain unchanged.
Certain learned values reside in the EEPROM, such as: ^
The Vehicle Identification Number (VIN)
^ The crankshaft variation learned position
^ The software/calibrations identification numbers
^ The control module security information
^ Flash Read Only Memory - Flash Memory
^ Flash memory has increased memory storage capacity. During programming, all information
within this type of memory is erased, and then replaced with entirely new information.
Service Programming Methods The 4 methods of programming a control module and the proper
tools for each method are as follows: ^
Remote Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle
^ Pass Thru Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle.
^ Off-Board Remote Programming, vehicle NOT available: The Tech 2 or other scan tool, Off-board Programming Adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
^ Off-Board Pass Thru Programming -
The Tech 2 or other scan tool, off-board programming adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
Before Programming A Control Module
IMPORTANT: DO NOT program an existing control module with the identical software/calibration
package. This procedure is not a short cut to correct a driveability condition. This is an ineffective
repair. A control module should only be programmed when the following occurs: ^
When a service procedure instructs you to replace the control module. The service part control
module does not contain operating software or calibrations.
^ General Motors Corporation releases an updated software/calibration package.
Ensure that the following conditions are met before programming a control module: ^
Vehicle system voltage: There are no charging system concerns. All charging system concerns must be repaired before
programming a control module.
- The battery voltage is greater than 12 volts but less than 16 volts. The battery must be fully
charged before programming the control module.
- A battery charger is NOT connected to the vehicles battery. Incorrect system voltage or voltage
fluctuations from a battery charger may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicles battery. Turn OFF or disable
systems such as: ^
Daytime Running Lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system.
^ Heating, Ventilation, And Air Conditioning (HVAC) systems
^ Engine cooling fans, etc
^ The ignition switch is in the proper position. The scan tool prompts you to turn ON the ignition,
with the engine OFF. DO NOT change the position of the ignition switch during the programming
procedure unless instructed to do so.
^ All tool connections are secure: The RS-232 cable
- The connection at the DLC
- The voltage supply circuits
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Powertrain Control Module (PCM) Programming (Off-board) > Page 4510
- The OBPA
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
^ If you are performing the pass-through programming procedure using a notebook computer
without the power cord, ensure that the internal battery is fully charged.
After Programming a Control Module The powertrain may operate slightly different after a control
module software/calibration update. Operating the powertrain through various driving conditions
allows the control module to re-learn certain values. The control module must re-learn the following
after a software/calibration update: ^
Fuel trim correction
^ Idle Air Control (IAC) learned position
^ Automatic transmission shift adapts
Other learned values only re-learn by performing a service procedure.
If a control module is replaced the following service procedures may need to be performed: ^
The crankshaft variation learn procedure
^ The engine oil life reset procedure
^ The idle learn procedure
^ The inspection/maintenance complete system set procedure
^ The vehicle theft deterrent password learn procedure
^ The Throttle Position (TP) sensor learn procedure
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Chevrolet Workshop Manuals > Powertrain Management > Relays and Modules - Powertrain Management > Relays and
Modules - Fuel Delivery and Air Induction > Fuel Pump Relay > Component Information > Locations > Fuel Pump Relay
Fuel Pump Relay: Locations Fuel Pump Relay
FUEL PUMP RELAY
Fuse Block - Underhood
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Page 4516
Locations View
The Fuel Pump (FP) Relay is located in the Underhood Fuse Block. The Underhood Fuse Block is
located at the left side of the engine compartment near the battery.
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Page 4517
Fuel Pump Relay: Locations Fuel Pump Relay Secondary - With Dual Tanks
SECONDARY FUEL PUMP RELAY (With Dual Tanks Only)
Locations View
The Secondary Fuel Pump (FP) Relay (1) is attached to the Underhood Fuse Block on bracket.
The Underhood Fuse Block is located at the left side of the engine compartment near the battery.
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Page 4518
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and Instructions
Fuel Pump Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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and Instructions > Page 4522
Electrical Symbols Part 2
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and Instructions > Page 4523
Electrical Symbols Part 3
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and Instructions > Page 4524
Electrical Symbols Part 4
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and Instructions > Page 4525
Fuel Pump Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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and Instructions > Page 4526
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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and Instructions > Page 4535
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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and Instructions > Page 4546
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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and Instructions > Page 4548
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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and Instructions > Page 4549
Various symbols are used in order to describe different service operations.
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and Instructions > Page 4550
Conversion - English/Metric
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and Instructions > Page 4551
Fuel Pump (FP) Relay-Secondary
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Ignition Relay: Locations
Locations View
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Fuse Block - Underhood
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Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTION
The ignition relay supplies battery positive voltage to the following components: ^
The fuel injectors
^ The ignition coils
^ The powertrain control module (PCM)
^ The throttle actuator control (TAC) module
DIAGNOSTIC AIDS
The following will occur if the ignition relay fails to close: ^
The engine cranks, but does not run.
^ Scan tool data will be available.
^ Instrument panel lights will illuminate.
TEST DESCRIPTION
Steps 1-5
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Steps 6-11
The numbers below refer to the step numbers on the diagnostic table. 2. This step is testing the
battery positive voltage circuit of the ignition relay. 3. This step is testing the ignition 1 positive
voltage circuit of the ignition relay. 4. This step is testing the coil ground circuit of the ignition relay.
5. This step isolates the circuits from the ignition relay. All of the circuits at the relay are good if the
test lamp illuminates.
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Switches - Computers and Control Systems > Accelerator Pedal Position Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Accelerator Pedal Position Sensor > Component Information > Locations >
Page 4564
Accelerator Pedal Position (APP) Sensor
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Page 4565
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Page 4566
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Locations View
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Information and Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Information and Instructions > Page 4574
Electrical Symbols Part 2
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Information and Instructions > Page 4575
Electrical Symbols Part 3
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Information and Instructions > Page 4576
Electrical Symbols Part 4
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Information and Instructions > Page 4577
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Information and Instructions > Page 4581
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Information and Instructions > Page 4582
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 4587
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 4589
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switches - Computers and Control Systems > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4594
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 4601
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 4602
Conversion - English/Metric
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Information and Instructions > Page 4603
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Switches - Computers and Control Systems > Camshaft Position Sensor > Component Information > Locations
Locations View
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Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 4631
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 4632
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Information and Instructions > Page 4633
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information and Instructions > Page 4634
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Information and Instructions > Page 4635
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information and Instructions > Page 4636
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 4637
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 4638
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 4639
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 4640
Conversion - English/Metric
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Information and Instructions > Page 4641
Camshaft Position (CMP) Sensor
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4642
Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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4643
Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Switches - Computers and Control Systems > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations
Locations View
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Switches - Computers and Control Systems > Coolant Temperature Sensor/Switch (For Computer) > Component
Information > Locations > Page 4647
Engine Coolant Temperature (ECT) Sensor
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Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
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1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
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Locations View
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Information and Instructions
Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information and Instructions > Page 4655
Electrical Symbols Part 1
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Information and Instructions > Page 4656
Electrical Symbols Part 2
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Information and Instructions > Page 4657
Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Information and Instructions > Page 4662
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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Information and Instructions > Page 4673
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4674
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4675
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4676
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Information and Instructions > Page 4677
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 4678
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Information and Instructions > Page 4679
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 4680
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information and Instructions > Page 4681
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 4682
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4683
Various symbols are used in order to describe different service operations.
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4684
Conversion - English/Metric
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Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4685
Crankshaft Position (CKP) Sensor
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4686
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Crankshaft Position Sensor > Component Information > Service and Repair >
CKP System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
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CKP System Variation Learn Procedure > Page 4689
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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CKP System Variation Learn Procedure > Page 4690
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
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CKP System Variation Learn Procedure > Page 4691
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Fuel Level Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Fuel Level Sensor > Component Information > Locations > Page 4695
Fuel Level Sensor: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
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Fuel Level Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations
Locations View
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Switches - Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page
4700
Fuel Tank Pressure (FTP) Sensor
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Switches - Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page
4701
Fuel Tank Pressure Sensor: Description and Operation
The FTP sensor measures the difference between the pressure or vacuum in the fuel tank and
outside air pressure. The control module provides a 5-volt reference and a ground to the FTP
sensor. The FTP sensor provides a signal voltage back to the control module that can vary
between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low
voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.
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4702
Fuel Tank Pressure Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel tank. 2. Remove the fuel pressure sensor (1).
INSTALLATION PROCEDURE
1. Install the fuel pressure sensor (1). 2. Install the fuel tank.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations > Page
4706
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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4707
Intake Air Temperature Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set > Page 4717
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins >
Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set > Page 4718
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set > Page 4724
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC
P0332 Set > Page 4725
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Page
4726
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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and Instructions > Page 4729
Electrical Symbols Part 1
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and Instructions > Page 4730
Electrical Symbols Part 2
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and Instructions > Page 4731
Electrical Symbols Part 3
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Switches - Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4732
Electrical Symbols Part 4
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and Instructions > Page 4733
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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and Instructions > Page 4734
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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and Instructions > Page 4736
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Knock Sensor (KS)
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Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
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Locations View
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Page 4766
Manifold Absolute Pressure (MAP) Sensor
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Manifold Pressure/Vacuum Sensor: Service and Repair
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield. 2. Disconnect the manifold absolute pressure (MAP) sensor
electrical connector.
3. Remove the MAP sensor (1) from the intake manifold.
INSTALLATION PROCEDURE
IMPORTANT: Lightly coat the MAP sensor seal with clean engine oil before installing the sensor.
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1. Install the MAP sensor (1). Push the MAP sensor down in order to engage the sensor into the
retainer.
2. Connect the MAP sensor electrical connector. 3. Install the engine sight shield.
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Engine Oil Level Switch
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Locations View
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Oxygen Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Oxygen Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4800
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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and Instructions > Page 4801
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4802
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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and Instructions > Page 4803
Equivalents - Decimal And Metric Part 1
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and Instructions > Page 4804
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4805
Various symbols are used in order to describe different service operations.
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Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4806
Conversion - English/Metric
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Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4807
Oxygen Sensor: Connector Views
Delphi
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Delphi)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Delphi)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4808
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Delphi)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Delphi)
Denso
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4809
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Denso)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Denso)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 4810
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Denso)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Denso)
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Page 4811
Oxygen Sensor: Description and Operation
HEATED OXYGEN SENSORS
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases. The PCM uses the
signal voltage from the fuel control HO2S in a Closed Loop in order to adjust the fuel injector pulse
width. While in a Closed Loop, the PCM can adjust fuel delivery in order to maintain an air to fuel
ratio which allows the best combination of emission control and driveability.
If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4814
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4815
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4816
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4817
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4818
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4819
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated
Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 4820
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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Locations View
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Information and Instructions
Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information and Instructions > Page 4826
Electrical Symbols Part 1
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Information and Instructions > Page 4827
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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Information and Instructions > Page 4828
Electrical Symbols Part 3
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Information and Instructions > Page 4829
Electrical Symbols Part 4
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Information and Instructions > Page 4830
Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Information and Instructions > Page 4831
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Information and Instructions > Page 4843
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 4844
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Information and Instructions > Page 4845
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Information and Instructions > Page 4846
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 4847
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4848
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4849
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Information and Instructions > Page 4850
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 4851
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information and Instructions > Page 4852
Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 4853
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 4854
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switches - Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4855
Conversion - English/Metric
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Information and Instructions > Page 4856
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
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Switches - Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information >
Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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Diagrams > 4L60-E > Page 4865
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Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Adjustments > 4L60-E > Page 4868
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
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Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Service and Repair > 4L60-E > Page 4872
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Locations View
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Switches - Fuel Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations >
Page 4878
Accelerator Pedal Position (APP) Sensor
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Page 4879
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Page 4880
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Locations View
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Information and Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Information and Instructions > Page 4888
Electrical Symbols Part 2
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Information and Instructions > Page 4889
Electrical Symbols Part 3
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Information and Instructions > Page 4890
Electrical Symbols Part 4
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Information and Instructions > Page 4891
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Information and Instructions > Page 4898
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information and Instructions > Page 4901
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 4903
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 4905
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 4908
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 4910
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 4912
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 4914
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 4915
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 4916
Conversion - English/Metric
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Information and Instructions > Page 4917
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Fuel Composition Sensor - W/L59 Only
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Flexible Fuel Sensor: Description and Operation
FUEL COMPOSITION SENSOR DESCRIPTION
The Fuel Composition Sensor (FCS), or flex fuel sensor (service parts term), measures the
ethanol-gasoline ratio of the fuel being used in a flexible fuel vehicle. Flexible fuel vehicles can be
operated with a blend of ethanol and gasoline, up to 85 percent ethanol. In order to adjust the
ignition timing and the fuel quantity to be injected, the engine management system requires
information about the percentage of ethanol in the fuel.
The FCS uses quick-connect style fuel connections, an incoming fuel connection, and an outgoing
fuel connection. The two connections have different diameters, to prevent incorrect attachment of
the fuel lines. All fuel passes through the fuel composition sensor before continuing on to the fuel
rail. The fuel composition sensor measures two different fuel related parameters, and sends an
electrical signal to the Powertrain Control Module (PCM) to indicate ethanol percentage, and fuel
temperature.
The fuel composition sensor has a three-wire electrical harness connector. The three wires provide
a ground circuit, a power source, and a signal output to the PCM. The power source is vehicle
system voltage, +12 volts), and the ground circuit connects to chassis ground. The signal circuit
carries both the ethanol percentage and fuel temperature within the same signal, on the same wire.
The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel
temp, and change an output signal accordingly. The electrical characteristic of the FCS signal is a
square-wave digital signal. The signal is both variable frequency and variable pulse width. The
frequency of the signal indicates the ethanol percentage, and the pulse width indicates the fuel
temperature. The PCM provides an internal pull-up to five volts on the signal circuit, and the FCS
pulls the 5 volts to ground in pulses. The output frequency is linear to the percentage of ethanol
content in the fuel. The normal range of operating frequency is between 50 and 150 Hertz, with 50
Hertz representing 0 percent ethanol, and 150 Hertz representing 100 percent ethanol. The normal
pulse width range of the digital pulses is between 1 and 5 milliseconds, with 1 millisecond
representing 40°C (-40°F), and 5 milliseconds representing 125°C (257°F).
The microprocessor inside the sensor is capable of a certain amount of self-diagnosis. An output
frequency of 170 Hertz indicates either that the fuel is contaminated or contains methanol (it should
not), or that an internal sensor electrical fault has been detected. Certain substances dissolved in
the fuel can cause the fuel to be contaminated, raising the output frequency to be higher than the
actual ethanol percentage should indicate. Examples of these substances include water, sodium
chloride (salt), and methanol.
It should be noted that it is likely that the FCS will indicate a slightly lower ethanol percentage than
what is advertised at the fueling station. This is not a fault of the sensor. The reason has to do with
government requirements for alcohol-based motor fuels. Government regulations require that
alcohol intended for use as motor fuel be DENATURED. This means that 100 percent pure ethanol
is first denatured with approximately 4% percent gasoline, before being mixed with anything else.
When an ethanol gasoline mixture is advertised as E85, the 85 percent ethanol was denatured
before being blended with gasoline, meaning an advertised E85 fuel contains only about 81
percent ethanol. The FCS measures the actual percentage of ethanol in the fuel.
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Flexible Fuel Sensor: Service and Repair
FUEL COMPOSITION SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Turn OFF the ignition. 2. Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure. 3.
Raise the vehicle. 4. Remove the fuel composition sensor fuel composition sensor (FCS)
attachment nuts (1).
5. Disconnect the FCS inlet and outlet pipes from the FCS.
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6. Disconnect the FCS electrical connector (1). 7. Remove the FCS and bracket assembly from the
frame rail.
8. Remove the FCS bolts and remove from the bracket.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the FCS to the bracket and install bolts.
Tighten Tighten bolts to 10 N.m (89 lb in).
2. Install FCS and bracket assembly to frame.
3. Install FCS bracket to frame nuts.
Tighten Tighten nuts (1) to 17 N.m (13 lb ft).
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4. Connect the FCS inlet and outlet pipes to the FCS.
5. Connect the FCS electrical connector (1). 6. Lower the vehicle. 7. Start the engine and check for
fuel leaks.
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Locations View
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Information and Instructions
Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Information and Instructions > Page 4934
Electrical Symbols Part 2
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Information and Instructions > Page 4935
Electrical Symbols Part 3
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Information and Instructions > Page 4936
Electrical Symbols Part 4
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Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Switches - Fuel Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions > Page 4953
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 4954
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Information and Instructions > Page 4956
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Information and Instructions > Page 4958
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Information and Instructions > Page 4960
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Information and Instructions > Page 4961
Various symbols are used in order to describe different service operations.
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Information and Instructions > Page 4962
Conversion - English/Metric
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Information and Instructions > Page 4963
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
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Locations View
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Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Instructions > Page 4974
Electrical Symbols Part 2
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Instructions > Page 4975
Electrical Symbols Part 3
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Instructions > Page 4976
Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Camshaft Position (CMP) Sensor
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Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Locations View
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Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5031
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5032
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5033
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5034
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5035
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5036
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5037
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5038
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5039
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5040
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5041
Crankshaft Position (CKP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Diagrams > Page 5042
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 5045
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 5046
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Crankshaft Position Sensor > Component Information > Service and Repair > CKP System
Variation Learn Procedure > Page 5047
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Ignition Switch > Ignition Switch Lock Cylinder > Component Information > Technical Service
Bulletins > Ignition Lock Cylinder - Revised Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5061
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for
Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5062
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
5068
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
5069
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Technical Service Bulletins > Page 5070
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Page 5074
Electrical Symbols Part 2
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Page 5075
Electrical Symbols Part 3
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Electrical Symbols Part 4
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Page 5077
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Page 5087
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Page 5089
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Knock Sensor (KS)
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Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Page 5105
Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Sensors and Switches - Powertrain Management > Sensors and
Switches - Ignition System > Knock Sensor > Component Information > Diagrams > Page 5106
1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > Specifications
Fuel Pressure: Specifications
Measure with the Key On Engine Off with the fuel pump commanded ON.
Vin (V,T,U)
Fuel Pressure (gasoline) .....................................................................................................................
................................................................. 55-62 psi
Vin (Z)
Fuel Pressure (ethanol) .......................................................................................................................
................................................................. 48-54 psi
These specifications are taken from the Fuel System Diagnosis. For complete testing of fuel
pressures and volume see Fuel System Diagnosis, See: Computers and Control Systems/Testing
and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal
Fuel Pressure: Testing and Inspection Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 5113
Fuel Pressure: Testing and Inspection Fuel System Diagnosis
SYSTEM DESCRIPTION
When you turn ON the ignition switch, the control module enables the fuel pump relay which
powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running
and the control module receives ignition reference pulses. If there are no ignition reference pulses,
the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the
ON position or if the engine stops.
The fuel tank stores the fuel supply. The electric fuel pump supplies fuel through an in-line fuel filter
to the fuel injection system. The pump provides fuel at a higher rate of flow than is needed by the
fuel injection system. The fuel pressure regulator maintains the correct fuel pressure to the fuel
injection system. A separate pipe returns unused fuel to the fuel tank.
TEST DESCRIPTION
Steps 1-2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 5114
Steps 3-7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 5115
Steps 8-13
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 5116
Steps 14-18
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 5117
Steps 19-25
The numbers below refer to the step numbers on the diagnostic table. 2. This step verifies that the
fuel pump is operating. 4. This step tests for an internal fuel leak. If the fuel pressure drops during
this test, then an internal loss of pressure is indicated. 6. This step tests the fuel pressure regulator.
The fuel pressure regulator is controlled by the engine vacuum. With the engine vacuum applied,
the
pressure should drop to the specified value.
9. This step inspects the fuel pressure regulator for a fuel leak from the vacuum port. If fuel leaks
from the fuel pressure regulator while the fuel
pump is commanded ON, replace the fuel pressure regulator.
10. This step tests for a loss of fuel pressure between the fuel feed pipe shut-off adapter and the
fuel pump. 11. This step tests for a leaking fuel injector or for a leaking fuel pressure regulator. If
the fuel pressure remains constant during this test, the fuel
injectors are not leaking fuel.
14. This step tests for a restricted fuel return pipe. If the fuel pressure is within the specified values,
there is a restriction in the fuel return pipe. 16. This step determines if the fuel pressure regulator or
the fuel pump is the cause of the low fuel pressure. If the pressure rises above the specified
value, the fuel pump is OK.
18. This step verifies that a circuit condition is not the cause of a fuel pressure concern. Thoroughly
inspect all fuel electrical circuits.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Idle Speed >
System Information > Specifications
Idle Speed: Specifications
Idle Speed ...........................................................................................................................................
.............................................................. 500-700 rpm
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Cleaner Restriction Indicator > Component Information > Description and Operation
Air Cleaner Restriction Indicator: Description and Operation
Air Cleaner Restriction Indicator
The air cleaner restriction indicator is located on the air cleaner assembly between the air filter and
the mass air flow (MAF) sensor.
If the area inside of the clear section is green, no air filter service is required. If the area inside the
clear section is orange and Change Air Filter appears, replace the air filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter
Element: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: Customer Interest Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter
Element: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 5133
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air
Filter Element: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: All Technical Service Bulletins Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air
Filter Element: > 04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 5139
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > Page 5140
Air Filter Element: Service and Repair
AIR CLEANER ELEMENT REPLACEMENT
REMOVAL PROCEDURE
1. Remove the intake duct (2). 2. Disconnect the electrical connector from the mass air flow/intake
air temperature (MAF/IAT) sensor.
3. Loosen the 4 fasteners (8) securing the air cleaner housing top cover (4). 4. Lift and rotate the
top cover (4) of the air cleaner housing to gain access to the air filter element. 5. Lift out the air filter
element (5). 6. Inspect the air filter element for dust, dirt, or water. Clean or replace the air filter
element if required.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Air Cleaner
Housing > Air Filter Element > Component Information > Technical Service Bulletins > Page 5141
1. Install the air filter element (5) into the air cleaner housing. 2. Rotate and install the top cover (4)
to the air cleaner housing (6). 3. Insert the fasteners (8) to secure the top cover.
4. Connect the MAF/IAT electrical connector. 5. Install the intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Filter > Fuel
Pressure Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Fuel Filter > Fuel
Pressure Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal > Page 5147
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Ignition Cable >
Component Information > Specifications
Ignition System Specifications
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Ignition Cable >
Component Information > Service and Repair > Spark Plug Wire Inspection
Ignition Cable: Service and Repair Spark Plug Wire Inspection
Spark plug wire integrity is vital for proper engine operation. A thorough inspection will be
necessary to accurately identify conditions that may affect engine operation. Inspect for the
following conditions:
^ Correct routing of the spark plug wires-Incorrect routing may cause cross-firing.
^ Any signs of cracks or splits in the wires.
^ Inspect each boot for the following conditions: Tearing
- Piercing
- Arcing
- Carbon tracking
- Corroded terminal
If corrosion, carbon tracking or arcing are indicated on a spark plug wire boot or on a terminal,
replace the wire and the component connected to the wire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Ignition Cable >
Component Information > Service and Repair > Spark Plug Wire Inspection > Page 5153
Ignition Cable: Service and Repair Spark Plug Wire Replacement
REMOVAL PROCEDURE
1. Disconnect the spark plug wire at each spark plug.
^ Twist each spark plug 1/2 turn.
^ Pull only on the boot in order to remove the wire from each spark plug.
2. Disconnect the spark plug wire from the ignition coil.
^ Twist each spark plug boot 1/2 turn.
^ Pull only on the boot in order to remove the wires from the ignition coil.
SPARK PLUG WIRE LENGTH V8
Spark Plug Wire Length V8
^ The Melco(R), square design, uses a spark plug wire (1) that is 145 mm (5.70 in) length cable
seal to cable seal.
^ The Delphi(R), round design uses a spark plug wire (2) that is 110 mm (4.30 in) length cable seal
to cable seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Ignition Cable >
Component Information > Service and Repair > Spark Plug Wire Inspection > Page 5154
Ignition Coils
^ There are 2 different manufacturers for the ignition coils, the Melco(R) (1) square design, and the
Delphi(R) (2) round design. These 2 coils use 2 different spark plug wire, and mounting brackets.
^ Melco(R), square design, coil mounting bracket (1).
^ Delphi(R), round design, coil mounting bracket (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Ignition Cable >
Component Information > Service and Repair > Spark Plug Wire Inspection > Page 5155
1. Install the spark plug wires at the ignition coil. 2. Install the spark plug wire to each spark plug. 3.
Inspect the wires for proper installation:
^ Push sideways on each boot in order to inspect the seating.
^ Reinstall any loose boot.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Technical Service Bulletins > Ignition System - New Spark Plugs & Gapping Info.
Spark Plug: Technical Service Bulletins Ignition System - New Spark Plugs & Gapping Info.
INFORMATION
Bulletin No.: 03-06-04-060B
Date: July 30 2008
Subject: Information on New Spark Plugs and Gapping
Models
Attention:
Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACOelco(R)
Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
Supercede:
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard
Corporate Bulletin Number 03-06-04-060A (Section 06 - Engine/Propulsion System).
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the different tip design the gap of the spark
plug has also changed.
^ The new spark plug P/N 12571164 with AC Delco P/N 41-985 is gapped to 1.01 mm (0.040 in)
when the spark plug is made.
Notice:
The spark plug gap is set during manufacturing and should not be changed or damage to the spark
plug may result. Any new spark plug found to not be properly gapped should not be used.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Technical Service Bulletins > Page 5160
Spark Plug: Specifications
This article has been updated with TSB #03-06-04-060B
INFORMATION ON NEW SPARK PLUGS AND GAPPING
SPARK PLUG GAP..............................................................................................................................
.................................................. 1.01 mm (0.040 in.)
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the
different tip design, the gap of the spark plug has also changed.
^ The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040
inches) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to
the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Technical Service Bulletins > Page 5161
Spark Plug: Application and ID
AC Plug Type ......................................................................................................................................
................................................................... 25171803
NGK Plug Type ....................................................................................................................................
................................................................. 12567759
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Service and Repair > Spark Plug Inspection
Spark Plug: Service and Repair Spark Plug Inspection
SPARK PLUG USAGE
^ Verify that the correct spark plug is installed. An incorrect spark plug causes driveability
conditions. Refer to Ignition System Specifications for the correct spark plug.
^ Ensure that the spark plug has the correct heat range. An incorrect heat range causes the
following conditions: Spark plug fouling-Colder plug
- Pre-ignition causing spark plug and/or engine damage-Hotter plug
SPARK PLUG INSPECTION
^ Inspect the terminal P05 (1) for damage. Inspect for a bent or broken terminal post (1).
- Test for a loose terminal post (1) by twisting and pulling the post. The terminal post (1) should
NOT move.
^ Inspect the insulator (2) for flashover or carbon tracking, soot. This is caused by the electrical
charge traveling across the insulator (2) between the terminal post (1) and ground. Inspect for the
following conditions: Inspect the spark plug boot for damage.
- Inspect the spark plug recess area of the cylinder head for moisture, such as oil, coolant, or
water. A spark plug boot that is saturated causes arcing to ground.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Service and Repair > Spark Plug Inspection > Page 5164
^ Inspect the insulator (2) for cracks. All or part of the electrical charge may arc through the crack
instead of the electrodes (3, 4).
^ Inspect for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to
Ignition System Specifications. An excessively wide electrode gap can prevent correct spark plug
operation.
- Inspect for the correct spark plug torque. Refer to Ignition System Specifications. Insufficient
torque can prevent correct spark plug operation. An over torqued spark plug, causes the insulator
(2) to crack.
- Inspect for signs of tracking that occurred near the insulator tip instead of the center electrode (4).
- Inspect for a broken or worn side electrode (3).
- Inspect for a broken, worn, or loose center electrode (4) by shaking the spark plug. ^
A rattling sound indicates internal damage.
^ A loose center electrode (4) reduces the spark intensity.
- Inspect for bridged electrodes (3, 4). Deposits on the electrodes (3, 4) reduce or eliminates the
gap.
- Inspect for worn or missing platinum pads on the electrodes (3, 4), if equipped.
- Inspect for excessive fouling.
^ Inspect the spark plug recess area of the cylinder head for debris. Dirty or damaged threads can
cause the spark plug not to seat correctly during installation.
SPARK PLUG VISUAL INSPECTION
^ Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal
combustion by-products from fuels with additives.
^ Carbon fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures ^
Leaking fuel injectors
^ Excessive fuel pressure
^ Restricted air filter element
^ Incorrect combustion
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Service and Repair > Spark Plug Inspection > Page 5165
- Reduced ignition system voltage output ^
Weak coils
^ Worn ignition wires
^ Incorrect spark plug gap
- Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that
normal combustion deposits may not burn off.
^ Deposit fouling-Oil, coolant, or additives that include substances such as silicone, very white
coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless
they form into a glazing over the electrode.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Spark Plug >
Component Information > Service and Repair > Spark Plug Inspection > Page 5166
Spark Plug: Service and Repair Spark Plug Replacement
REMOVAL PROCEDURE
1. Remove the spark plug wires. 2. Loosen each spark plug 1 or 2 turns. 3. Brush or air blast away
any dirt from around the spark plugs. 4. Remove the spark plugs 1 at a time. Place each plug in a
tray marked with the corresponding cylinder numbers.
INSTALLATION PROCEDURE
1. Properly position each spark plug washer. 2. Inspect each spark plug gap. Adjust each plug as
needed.
Specification Spark plug gap: 1.52 mm (0.060 in)
NOTE: Refer to Fastener Notice in Service Precautions.
3. Hand start the spark plugs in the corresponding cylinders. 4. Tighten the spark plugs.
Tighten ^
For used heads tighten the spark plugs to 15 N.m (11 lb ft).
^ For new aluminum heads tighten the spark plugs to 20 N.m (15 lb ft).
^ For new iron heads, tighten the spark plugs to 30 N.m (22 lb ft).
5. Install the spark plug wires.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Compression
Check > System Information > Specifications
Compression Check: Specifications
The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure
in any one cylinder is 1035 kPa (150 psi), the lowest allowable pressure for any other cylinder
would be 725 kPa (105 psi). (1035 x 70% = 725) (150 x 70% = 105).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Compression
Check > System Information > System Diagnosis > Engine Compression Test (Electronic Throttle)
Compression Check: Testing and Inspection Engine Compression Test (Electronic Throttle)
Engine Compression Test (Electronic Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Turn the ignition to the ON position. 6.
Depress the accelerator pedal to position the throttle plate wide open. 7. Start with the compression
gauge at zero and crank the engine through four compression strokes, four puffs. 8. Check the
compression for each cylinder. Record the readings. 9. If a cylinder has low compression, inject
approximately 15 ml. (1 tablespoon) of engine oil into the combustion chamber through the spark
plug
hole. Recheck the compression and record the reading.
10. The minimum compression in any one cylinder should not be less than 70 percent of the
highest cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Then compression builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Compression
Check > System Information > System Diagnosis > Engine Compression Test (Electronic Throttle) > Page 5172
Compression Check: Testing and Inspection Engine Compression Test (Mechanical Throttle)
Engine Compression Test (Mechanical Throttle)
1. Charge the battery if the battery is not fully charged. 2. Disable the ignition system. 3. Disable
the fuel injection system. 4. Remove all the spark plugs. 5. Block the throttle plate wide open. 6.
Start with the compression gauge at zero and crank the engine through four compression strokes,
four puffs. 7. Make the compression check for each cylinder. Record the reading. 8. If a cylinder
has low compression, inject approximately 15 ml. (1 tablespoon) of engine oil into the combustion
chamber through the spark plug
hole. Recheck the compression and record the reading.
9. The minimum compression in any one cylinder should not be less than 70 percent of the highest
cylinder. No cylinder should read less than 690
kPa (100 psi). For example, if the highest pressure in any one cylinder is 1035 kPa (150 psi), the
lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1035 x 70% = 725)
(150 x 70% = 105). Normal-Compression builds up quickly and evenly to the specified compression for each cylinder.
- Piston Rings Leaking-Compression is low on the first stroke. Compression then builds up with the
following strokes but does not reach normal. Compression improves considerably when you add
oil.
- Valves Leaking-Compression is low on the first stroke. Compression usually does not build up on
the following strokes. Compression does not improve much when you add oil.
- If two adjacent cylinders have lower than normal compression and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the
cylinders.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Tune-up and Engine Performance Checks > Valve Clearance >
System Information > Specifications
Valve Clearance: Specifications
The manufacturer indicates that this vehicle has hydraulic lifters or adjusters and therefore does
not require adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Accelerator Pedal Position
Sensor > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 5180
Accelerator Pedal Position (APP) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 5181
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 5182
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 5183
1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5189
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5190
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5191
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5192
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5193
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Component Information > Diagrams > Diagram Information and Instructions > Page 5194
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 5195
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5196
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5198
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Component Information > Diagrams > Diagram Information and Instructions > Page 5218
Conversion - English/Metric
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Component Information > Diagrams > Diagram Information and Instructions > Page 5219
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Intake Air Temperature
Sensor > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Intake Air Temperature
Sensor > Component Information > Locations > Page 5225
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Intake Air Temperature
Sensor > Component Information > Locations > Page 5226
Intake Air Temperature Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Body Control Module >
Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Body Control Module >
Component Information > Diagrams > Diagram Information and Instructions
Body Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Body Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Component Information > Diagrams > Diagram Information and Instructions > Page 5263
Body Control Module: Connector Views
Body Control Module Connector (BCM) - C1
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Body Control Module (BCM) - C2
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Body Control Module (BCM) - C3
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Body Control Module: Electrical Diagrams
Controlled/Monitored Subsystem References
Controlled/Monitored Subsystem References
Body Control Module Schematics: Controlled/Monitored Subsystem References
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Exterior Lighting Systems References
Exterior Lighting Systems References
Body Control Module Schematics: Exterior Lighting Systems References
Interior Lighting Systems References
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Interior Lighting Systems References
Body Control Module Schematics: Interior Lighting Systems References
Power, Ground and Serial Data
Power, Ground and Serial Data
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Body Control Module Schematics: Power, Ground And Serial Data
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Body Control Module >
Component Information > Service and Repair > Procedures
Body Control Module: Procedures
IMPORTANT: If any module is replaced, programming the module with the proper RPO
configurations must be done prior to performing the Passlock Learn procedure.
1. The BCM must be programmed with the proper RPO configurations. The BCM stores the
information regarding the vehicle options. If the BCM is
not properly configured with the correct RPO codes the BCM will not control the features properly.
Ensure that the following conditions exist in order to prepare for BCM programming: ^
The battery is fully charged.
^ The ignition switch is in the RUN position.
^ The DLC is accessible.
^ All disconnected modules and devices are reconnected before programming.
2. Follow the SPS instructions on the Techline Terminal and scan tool to program the BCM. 3. If
the BCM fails to accept the program, perform the following steps:
^ Inspect all BCM connections.
^ Verify that the SPS Techline Terminal and scan tool have the latest software version.
Passlock Learn Procedures Refer to the Theft Deterrent sub-system for the appropriate learn
procedure.
IMPORTANT: After programming, perform the following to avoid future misdiagnosis: 1. Turn the
ignition OFF for 10 seconds. 2. Connect the scan tool to the data link connector. 3. Turn the ignition
ON with the engine OFF. 4. Use the scan tool in order to retrieve History DTCs from all modules. 5.
Clear all history DTCs.
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Body Control Module: Removal and Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
1. Disconnect the negative battery cable(s). 2. Remove the knee bolster.
3. Disconnect the brown connector. 4. Disconnect all other connectors (1). 5. Remove the BCM
from the sliding bracket.
INSTALLATION PROCEDURE
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1. Slide the BCM onto the bracket. 2. Connect all the connectors (1) except the brown connector. 3.
Connect the brown connector.
4. Install the knee bolster. 5. Connect the negative battery cable(s). 6. Reprogram the BCM.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Camshaft Position Sensor >
Component Information > Locations
Locations View
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Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Camshaft Position (CMP) Sensor
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Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Coolant Temperature
Sensor/Switch (For Computer) > Component Information > Locations
Locations View
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Engine Coolant Temperature (ECT) Sensor
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Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
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1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Locations
Locations View
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Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5348
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5349
Equivalents - Decimal And Metric Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5350
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5351
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5352
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5353
Crankshaft Position (CKP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Diagrams > Page 5354
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Service and Repair > CKP System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Service and Repair > CKP System Variation Learn Procedure > Page 5357
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Service and Repair > CKP System Variation Learn Procedure > Page 5358
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Crankshaft Position Sensor >
Component Information > Service and Repair > CKP System Variation Learn Procedure > Page 5359
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Data Link Connector >
Component Information > Locations > Data Link Connector (DLC)
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Data Link Connector >
Component Information > Locations > Data Link Connector (DLC) > Page 5364
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Data Link Connector >
Component Information > Locations > Page 5365
Data Link Connector: Diagrams
Splice Pack SP205
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Data Link Connector >
Component Information > Locations > Page 5366
Data Link Connector (DLC)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Data Link Connector >
Component Information > Locations > Page 5367
Data Link Connector: Service and Repair
REMOVAL PROCEDURE
1. Remove the bolt from the data link connector. 2. Remove the data link connector from the
instrument panel.
INSTALLATION PROCEDURE
1. Install the data link connector to the instrument panel.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the data link connector bolt.
Tighten Tighten the bolt to 6 N.m (53 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Actuator >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Actuator >
Component Information > Locations > Page 5371
Throttle Actuator Control (TAC) Motor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations
Electronic Throttle Control Module: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations > Page 5375
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations > Page 5376
Electronic Throttle Control Module: Diagrams
Throttle Actuator Control (TAC) Module Connector C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations > Page 5377
Throttle Actuator Control (TAC) Module Connector C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations > Page 5378
Electronic Throttle Control Module: Description and Operation
THROTTLE ACTUATOR CONTROL (TAC) MODULE
Throttle Actuator Control (TAC) Module
The TAC module is the control center for the electronic throttle system. The TAC module and the
powertrain control module (PCM) communicate via a dedicated redundant serial data circuit. The
TAC module and the PCM monitor the commanded throttle position and compare the commanded
position to the actual throttle position. This is accomplished by monitoring the APP and the TP
sensor. These 2 values must be within a calibrated value of each other. The TAC module also
monitors each individual circuit of the TP sensor and the APP to verify proper operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Electronic Throttle Control
Module > Component Information > Locations > Page 5379
Electronic Throttle Control Module: Service and Repair
THROTTLE ACTUATOR CONTROL (TAC) MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Release the retainer tab from the left side of the throttle actuator control (TAC) module. 2. Slowly
slide the TAC module out of the retaining bracket. 3. Disconnect the TAC module connectors from
the TAC module.
INSTALLATION PROCEDURE
1. Connect the TAC module connectors to the TAC module. 2. Slide the TAC module into the TAC
module bracket. 3. Push the TAC module towards the bracket in order to snap the TAC module into
the bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls MIL ON/Misfire/Misfire DTC's Set
Engine Control Module: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls MIL ON/Misfire/Misfire DTC's Set > Page 5388
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Engine Control Module: >
04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Engine Control Module: >
04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket Accessory Usage > Page 5394
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Engine Control Module: >
06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Engine Control Module: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire
DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Engine Control Module: >
06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set > Page 5399
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Engine Control Module: >
04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
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results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
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Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
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Engine Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Engine Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 5423
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 5438
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Engine Control Module: Connector Views
Powertrain Control Module (PCM) C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Powertrain Control Module (PCM) C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Powertrain Control Module (PCM) C1 Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Diagrams > Diagram Information and Instructions > Page 5442
Powertrain Control Module (PCM) C2 Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Diagrams > Diagram Information and Instructions > Page 5443
Powertrain Control Module (PCM) C2 Part 2
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Diagrams > Diagram Information and Instructions > Page 5444
Powertrain Control Module (PCM) C2 Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Description and Operation > Electronic Ignition (EI) System Description
Engine Control Module: Description and Operation Electronic Ignition (EI) System Description
POWERTRAIN CONTROL MODULE (PCM)
The PCM controls all ignition system functions, and constantly corrects the basic spark timing. The
PCM monitors information from various sensor inputs that include the following:
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Mass Airflow (MAF) sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Vehicle Speed Sensor (VSS)
^ The transmission gear position or range information sensors
^ The Engine Knock Sensors (KS)
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Description and Operation > Electronic Ignition (EI) System Description > Page 5447
Engine Control Module: Description and Operation Powertrain Control Module (PCM) Description
General Information
The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while
maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ The fuel control
^ The Ignition Control (IC)
^ The Knock Sensor (KS) system
^ The automatic transmission shift functions
^ The manual transmission
^ The cruise control enable, if equipped
^ The generator
^ The evaporative emissions (EVAP) purge
^ The A/C clutch control, if equipped
^ The secondary air injection (AIR), if equipped
^ The Exhaust Gas Recirculation (EGR)
PCM Function
The PCM supplies a buffered voltage to various sensors and switches. The PCM controls most
components with electronic switches which complete a ground circuit when turned ON.
Powertrain Control Module
Powertrain Control Module
The Powertrain Control Module (PCM) is located in the engine compartment. The PCM is the
control center of the vehicle. The PCM controls the following:
^ The fuel metering system
^ The transmission shifting
^ The ignition timing
^ The on-board diagnostics for powertrain functions
The PCM constantly monitors the information from various sensors and controls the systems that
affect vehicle performance and emissions. The PCM also performs the diagnostic functions for
those systems. The PCM can recognize operational problems and alert the driver through the
Malfunction Indicator Lamp (MIL) when a malfunction has occurred. When a malfunction is
detected, the PCM stores a Diagnostic Trouble Code (DTC) which helps to identify problem areas.
This is done to aid the technician in making repairs.
The PCM supplies either 5.0 or 12.0 volts to power various sensors and switches. This is done
through resistances in the PCM. The resistance is so high in value that a test lamp does not
illuminate when connected to the circuit. In some cases, even an ordinary shop voltmeter does not
give an accurate reading because the voltmeters resistance is too low. Therefore, a DMM with a
minimum of 10 megaohms input impedance is required to ensure accurate voltage readings.
The PCM controls output circuits such as the fuel injectors, the Idle Air Control (IAC), the cooling
fan relays, etc. by controlling the ground or the power feed circuit through transistors or a device
called an output driver module.
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Torque Management
Torque management is a function of the PCM that reduces engine power under certain conditions.
Torque management is performed for the following reasons:
1. To prevent over-stressing the powertrain and driveline components 2. To prevent damage to the
vehicle during certain abusive maneuvers 3. To reduce engine speed when the IAC is out of the
normal operating range
The PCM monitors the following sensors and engine parameters in order to calculate engine output
torque:
^ The air/fuel ratio
^ The Mass Air Flow (MAF) sensor
^ The Manifold Absolute Pressure (MAP) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The spark advance
^ The engine speed
^ The Engine Coolant Temperature (ECT) Sensor
^ The A/C clutch status
The PCM monitors the torque converter status, the transmission gear ratio, and the engine speed
in order to determine if torque reduction is required. The PCM retards the spark as appropriate to
reduce engine torque output if torque reduction is required. The PCM also shuts OFF the fuel to
certain injectors in order to reduce the engine power in the case of an abusive maneuver.
The following are instances when engine power reduction is likely to be experienced:
^ During transmission upshifts and downshifts
^ During heavy acceleration from a standing start
^ When the clutch pedal is released too quick under a heavy load, 6.0L only
^ When one set of drive axles looses traction while the other set of drive axles are not moving, 4
Wheel Drive only and in 4WD low
^ If the IAC is out of the normal operating range, except 6.0L
^ When the driver is performing harsh or abusive maneuvers such as shifting into gear at high
throttle angles or shifting the transmission from reverse to drive to create a rocking motion
The driver is unlikely to notice the torque management actions in the first 2 instances. The engine
power output is moderate at full throttle in the other cases.
The PCM calculates the amount of spark retard necessary to reduce the engine power by the
desired amount. The PCM disables the fuel injectors for cylinders 1, 4, 6, and 7 in the case of an
abusive maneuver.
Basic Knowledge Required
Without a basic knowledge of electricity, you will have difficulty using the diagnostic procedures.
You should understand the basic theory of electricity and know the meaning of voltage-volts,
current-amps, and resistance-ohms. You should understand what happens in a circuit with an open
or a shorted wire. You should be able to read and understand a wiring diagram.
PCM Service Precautions
The PCM is designed to withstand normal current draws associated with vehicle operations. Avoid
overloading any circuit. When testing for opens or shorts, do not ground any of the PCM circuits
unless instructed. When testing for opens or shorts, do not apply voltage to any of the PCM circuits
unless instructed. Only test these circuits with a DMM while the PCM connectors remain
connected.
Engine Controls Information
The driveability and emissions information describes the function and operation of the powertrain
control module (PCM).
The engine controls Information contains the following:
^ Component locations
^ Wiring diagrams
^ PCM terminal end view and terminal definitions
^ Diagnostic System Check-Computers and Controls Systems
^ Diagnostic trouble code (DTC) tables
The component system includes the following items:
^ Component and circuit description
^ On-vehicle service for each sub-system
^ Functional checks and diagnostic tables
The DTCs also contain diagnostic support information containing circuit diagrams, circuit or system
information, and helpful diagnostic information.
System Status and Drive Cycle For Inspection/Maintenance
The System Status selection is included in the scan tool System Info menu.
Several states require that the I/M (OBD II system) pass on-board tests for the major diagnostics
prior to having a vehicle emission inspection. This is
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Component Information > Description and Operation > Electronic Ignition (EI) System Description > Page 5449
also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the System Status, complete or not complete, in
order to verify that the vehicle meets the criteria to comply with local area requirements. Using the
System Status display, any of the following systems or combination of systems may be monitored
for I/M Readiness:
^ The catalyst
^ The Evaporative Emission (EVAP) system
^ The Heated Oxygen Sensors (HO2S)
^ The HO2S heater
^ The Exhaust Gas Recirculation (EGR) system
^ The secondary air injection (AIR) system
IMPORTANT: The System Status display indicates only whether or not the test has been
completed. The System Status display does not necessarily mean that the test has passed. If a
Failed Last Test indication is present for a DTC associated with one of the above systems,
diagnosis and repair is necessary in order to meet the I/M requirement. Verify that the vehicle
passes all of the diagnostic tests associated with the displayed System Status prior to returning the
vehicle to the customer. Refer to the Typical Drive Cycle table, more than one drive cycle may be
needed, to use as a guide to complete the I/M System Status tests.
Typical Drive Cycle
Following a DTC info clear, System Status clears for one or all of these systems. Following a
battery disconnect or a PCM replacement, all System Status information clears.
Primary System Based Diagnostics
There are primary system-based diagnostics which evaluate the system operation and their effect
on vehicle emissions. The primary system-based diagnostics are listed below, with a brief
description of the diagnostic functionality.
Oxygen Sensor Diagnosis
Diagnose the fuel control heated oxygen sensors (HO2S) for the following conditions:
^ Heater performance, heater current monitor
^ Response switches, number or switches R/L or L/R
^ Response time, time to switch R/L or L/R
^ Inactive signal, output steady at bias voltage - approximately 450 mV
^ Signal fixed high
^ Signal fixed low
Diagnose the catalyst monitor HO2S for the following functions:
^ Heater performance, heater current monitor
^ Signal fixed low
^ Signal fixed high
^ Inactive sensor
Heated Oxygen Sensors
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases.
The PCM uses the signal voltage from the fuel control HO2S in a Closed Loop in order to adjust
the fuel injector pulse width. While in a Closed Loop, the PCM can adjust fuel delivery in order to
maintain an air to fuel ratio which allows the best combination of emission control and driveability.
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If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Catalyst Monitor Heated Oxygen Sensors
In order to control emissions of HydroCarbons (HC), Carbon Monoxide (CO), and Oxides Of
Nitrogen (NOx), the system uses a TWC. The catalyst promotes a chemical reaction which oxidizes
the HC and CO present in the exhaust gas, converting the HC and CO into harmless water vapor
and carbon dioxide. The catalyst also converts NOx to nitrogen. Catalyst monitor HO2S,
post-catalyst HO2S, are always located downstream of the catalytic converter.
The PCM has the ability to monitor this process using the post catalyst HO2S. The pre-sensors
produce an output signal which indicates the amount of oxygen present in the exhaust gas entering
the TWC. The post sensor produces an output signal which indicates the oxygen storage capacity
of the catalyst. This in turn indicates the catalysts ability to convert exhaust gases efficiently. If the
catalyst is operating efficiently, the pre-HO2S signal is far more active than that produced by the
post-HO2S.
In addition to catalyst monitoring, the post-HO2S has a limited role in controlling fuel delivery. If the
post-HO2S signal indicates a high or low oxygen content for an extended period of time while in a
Closed Loop, the PCM adjusts the fuel delivery slightly in order to compensate.
Catalyst Monitor Diagnostic Operation
The catalyst monitor diagnostic measures oxygen storage capacity of the catalyst converter. In
order to do this, the HO2S are installed before and after the TWC. Voltage variations between the
sensors allow the PCM to determine the catalyst emission performance.
As a catalyst becomes less effective in promoting chemical reactions, the catalysts capacity to
store and release oxygen generally degrades. The catalyst monitor diagnostic is based on a
correlation between conversion efficiency and oxygen storage capacity.
A good catalyst, e.g. 95 percent hydrocarbon conversion efficiency, shows a relatively flat output
voltage on the post-catalyst HO2S. A degraded catalyst, 65 percent hydrocarbon conversion,
shows a greatly increased activity in output voltage from the post catalyst HO2S.
The post-catalyst HO2S is used to measure the oxygen storage and release capacity of the
catalyst. A high oxygen storage capacity indicates a good catalyst. Low oxygen storage capacity
indicates a failing catalyst. The TWC and the HO2S must be at operating temperature in order to
achieve correct oxygen sensor voltages like those shown in the post-catalyst HO2S outputs
graphic.
The catalyst monitor diagnostic is sensitive to the following conditions:
^ Exhaust leaks
^ HO2S contamination
^ Alternative fuels
Exhaust system leaks may cause the following:
^ Prevent a degraded catalyst from failing the diagnostic
^ Cause a false failure for a normally functioning catalyst
^ Prevent the diagnostic from running
Some of the contaminants that may be encountered are phosphorus, lead, silica, and sulfur. The
presence of these contaminants prevent the TWC diagnostic from functioning properly.
Three-Way Catalyst Oxygen Storage Capacity
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Component Information > Description and Operation > Electronic Ignition (EI) System Description > Page 5451
Three-Way Catalyst Oxygen Storage Capacity
The PCM must monitor the TWC system for efficiency. In order to accomplish this, the PCM
monitors the pre-catalyst and post-catalyst HO2S. When the TWC is operating properly, the
post-catalyst (2) HO2S shows significantly less activity than the pre-catalyst (1) HO2S. The TWC
stores oxygen during the normal reduction and oxidation process. The TWC releases oxygen
during the normal reduction and oxidation process. The PCM calculates the oxygen storage
capacity using the difference between the pre-catalyst and post-catalyst HO2S voltage levels.
Whenever the sensor activity of the post-catalyst (2) HO2S nears the sensor activity of the
pre-catalyst (1) HO2S, the catalysts efficiency is degraded. Aftermarket HO2S characteristics may
be different from the original equipment manufacturer sensor. This may lead to a false pass or a
false fail of the catalyst monitor diagnostic. Similarly, if an aftermarket catalyst does not contain the
same amount of precious metal content as the original part, the correlation between oxygen
storage and conversion efficiency may be altered enough to set a false DTC.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft rotational velocity, aka reference period,
variations. The PCM determines crankshaft rotational velocity using the Crankshaft Position (CKP)
Sensor and Camshaft Position (CMP) Sensor. When a cylinder misfires, the crankshaft slows down
momentarily. By monitoring the crankshaft and CMP sensor signals, the PCM can calculate when a
misfire occurs.
For a non-catalyst damaging misfire, the diagnostic is required to monitor a misfire present for
between 1,000-3,200 engine revolutions.
For catalyst damage misfire, the diagnostic responds to the misfire within 200 engine revolutions
Rough roads may cause false misfire detection. A rough road applies sudden torque variations to
the drive wheels and drivetrain. This torque can intermittently decrease the crankshaft rotational
velocity. The Antilock Braking (ABS) System detects uneven speed between the vehicles wheels
and sends data via the serial data bus to the PCM to disable the misfire monitor until the rough
road is no longer detected.
On automatic transmission equipped vehicles, the Torque Converter Clutch (TCC) disables
whenever a misfire is detected. Disabling the TCC isolates the engine from the rest of the drive line
and minimizes the affect of the drive wheel inputs on crankshaft rotation.
When the TCC has disabled as a result of misfire detection, the TCC is re-enabled after
approximately 3,200 engine revolutions if no misfire is detected. The TCC remains disabled
whenever the misfire is detected, with or without a DTC set. This allows the misfire diagnostic to
reevaluate the system.
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Component Information > Description and Operation > Electronic Ignition (EI) System Description > Page 5452
Whenever a cylinder misfires, the misfire diagnostic counts the misfire and notes the crankshaft
position at the time the misfire occurred.
A current and a history misfire counter is maintained for each cylinder. The misfire current
counters, Misfire Cur #1-8, indicate the number of firing events out of the last 200 cylinder firing
events which were misfires. The misfire current counters displays real time data without a misfire
DTC stored. The misfire history counters, Misfire Hist #1-8, indicate the total number of cylinder
firing events which were misfires. The misfire history counters display 0 until the misfire diagnostic
has failed and a DTC P0300 is set. Once the misfire DTC sets, the misfire history counters will be
updated every 200 cylinder firing events. The Misfire counters graphic illustrates how these misfire
counters are maintained.
When crankshaft rotation is erratic, the PCM detects a misfire condition. Because of this erratic
condition, the data that is collected by the diagnostic can sometimes incorrectly identify which
cylinder is misfiring. The Misfire Counters graphic shows there are misfires counted from more than
one cylinder. Cylinder #1 has the majority of counted misfires. In this case, the misfire counters
would identify cylinder #1 as the misfiring cylinder. The misfires in the other counters were just
background noise caused by the erratic rotation of the crankshaft. If the number of accumulated
misfires is sufficient for the diagnostic to identify a true misfire, the diagnostic will set DTC
P0300-Misfire Detected. The illustration depicts an accumulation in the history buffers.
If two cylinders in sequential tiring order are both misfiring, the first misfiring cylinder will
accumulate misfires in the cylinder buffer, but the second misfiring cylinder will not. This is because
the PCM compares a misfiring cylinder with the cylinder 90 degrees prior to that cylinder in the
firing order. Therefore the PCM would be comparing crankshaft speed of the second misfiring
cylinder to an already suspect cylinder. The PCM however, will be able to detect both misfiring
cylinders after the engine exceeds 2,000 RPM. This is because the PCM then starts to compare
misfires to the opposing cylinder rather than the previous cylinder in the firing order.
Use Techline equipment to monitor the misfire counter data on applicable vehicles. Knowing which
specific cylinders misfire can lead to the root cause. Using the information in the misfire counters
identifies which cylinders are misfiring. If the counters indicate cylinders number 1 and 4 misfired,
look for a circuit or component common to both cylinders.
The misfire diagnostic may indicate a fault due to a temporary fault not necessarily caused by a
vehicle emission system malfunction. Examples include the following items:
^ Contaminated fuel
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^ Running out of fuel
^ Fuel fouled spark plugs
^ Basic engine fault
Fuel Trim System Operation
The fuel trim system monitors the averages of short-term and long-term fuel trim values. If these
fuel trim values stay at the individual limits for a calibrated period of time, a malfunction is indicated.
The fuel trim diagnostic compares the average of short and long-term fuel trim values. If either
value is within the thresholds, a pass is recorded. If either value is outside the thresholds, a rich or
lean fuel trim DTC will set.
Comprehensive Component Monitor Diagnostic
Comprehensive component monitoring diagnostics are required to monitor emissions-related input
and output powertrain components.
Input Components The PCM monitors the input components for circuit continuity and out-of-range
values. This includes performance checking. Performance checking refers to indicating a fault
when the signal from a sensor does not seem reasonable, such as a Throttle Position (TP) sensor
that indicates high throttle position at low engine loads or manifold Absolute Pressure (MAP)
Voltage. The input components may include, but are not limited to, the following sensors: ^
The Vehicle Speed (VSS) Sensor
^ The Mass Air Flow (MAF) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Crankshaft Position (CKP) Sensor
^ The Knock Sensor (KS)
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Camshaft Position (CMP) Sensor
^ The Manifold Absolute Pressure (MAP) Sensor
In addition to the circuit continuity and rationality check, the engine coolant temperature (ECT)
sensor is monitored for the sensors ability to achieve a steady state temperature to enable Closed
Loop fuel control.
Output Components Diagnose the output components for the proper response to PCM commands.
Components where functional monitoring is not feasible will be monitored for circuit continuity and
out-of-range values if applicable.
Output components to be monitored include, but are not limited to, the following circuits: ^
The Idle Air Control (IAC) Motor
^ The Evaporative Emission (EVAP) System
^ The electronic transmission controls
^ The A/C relay, if equipped
^ The VSS output
^ The Malfunction Indicator Lamp (MIL) Control
^ The cruise control enable, if equipped
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Service and Repair > Powertrain Control Module (PCM) Programming (Off-board)
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(Off-board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: ^
DO NOT program a control module unless you are directed by a service procedure or you are
directed by a General Motors Corporation service bulletin. Programming a control module at any
other time will not permanently correct a customer's concern.
^ The Off-Board Programming is used in situations where a control module must be programmed
without having the vehicle present. The Off-Board Programming Adapter must be used to perform
the Off-Board Programming procedure. The adapter allows the control module to power up and
allows the Tech 2 to communicate with the control module.
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
Ensure that all connections are secure at the following locations: ^
The Off-Board Programming Adapter
^ The Tech 2
^ The control module
^ The Techline terminal
OFF-BOARD PROGRAMMING
1. Obtain the VIN of the vehicle for which the control module is being programmed. 2. With the
Techline terminal, select Service Programming. 3. Select Tech 2, Reprogram ECU, and Off-Board
Programming Adapter as the ECU location. 4. Connect the control module, Off-Board
Programming Adapter, and the Tech 2 as described on the Techline terminal. Ensure you use the
correct
harness connector from the Off-Board Programming Adapter kit.
5. With the Tech 2, select Service Programming Request Information function. The Tech 2
communicates with the control module and receives the
access code.
6. With the Tech 2, exit the Service Programming Request Information. 7. Disconnect the Tech 2
from the Off-Board Programming Adapter. 8. Connect the Tech 2 to the Techline terminal. 9. Turn
ON the Tech 2.
10. With the Techline terminal, enter the VIN of the vehicle that will be receiving the control module.
11. The Techline terminal will display the message, attaching to database. 12. Identify what type of
programming that you are performing. 13. Select the appropriate calibration file. 14. Ensure all
connections are secure. 15. The Techline terminal displays a summary screen that summarizes
your selections. After confirming you choices, the Techline terminal
automatically loads the calibration files to the Tech 2.
16. After the download is complete, turn OFF the Tech 2. 17. Disconnect the Tech 2 from the
Techline terminal. 18. Connect the Tech 2 to the Off-Board Programming Adapter. 19. With the
Tech 2, select Service Programming.
IMPORTANT: DO NOT turn OFF the Off-Board Programming Adapter if the programming
procedure is interrupted or unsuccessful. Ensure the control module and the Off-Board
Programming Adapter connections are secure and the Techline operating software is up to date.
Attempt to reprogram the control module. If the control module cannot be programmed, replace the
control module.
20. With the Tech 2, select Program. 21. After the download is complete, exit Service
Programming. 22. Turn OFF the Off-Board Programming Adapter.
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Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(On-Board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: DO NOT program a control module unless you are directed by a service procedure
or you are directed by a General Motors Corporation service bulletin. Programming a control
module at any other time will not permanently correct a customers concern.
Ensure the following conditions are met before programming a control module: ^
Vehicle system voltage There is no charging system concern. All charging system concerns must be repaired before
programming a control module.
- Battery voltage is greater than 12 volts but less than 16 volts. The battery must be charged before
programming the control module if the battery voltage is low.
- A battery charger is NOT connected to the vehicle's battery. Incorrect system voltage or voltage
fluctuations from a battery charger, may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicle's battery. ^
Twilight sentinel
^ Interior lights
^ Daytime running lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system. Refer to the Owners manual.
^ HVAC systems
^ Cooling System fans, etc.
^ The ignition is in the proper position. The scan tool prompts you to turn ON the ignition, with the
engine OFF. DO NOT change the position of the ignition switch during the programming procedure,
unless instructed to do so.
^ All tool connections are secure. RS-232
- The connection at the DLC is secure.
- Voltage supply circuits
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
REMOTE PROGRAMMING
1. Turn OFF the ignition. 2. Install the Tech 2 to the data link connector (DLC). 3. Turn ON the
ignition, with the engine OFF. 4. Turn OFF all vehicle accessories. 5. With the Tech 2, select
Service Programming. 6. Identify vehicle information as requested by the Tech 2. 7. Select the type
of module you are programming. 8. Select the type of programming to be performed. 9. Verify the
displayed VIN with the vehicle VIN. If the displayed VIN does not match the actual VIN, write down
the actual VIN and correct the
VIN at the Techline terminal.
10. When complete, Exit Service Programming. 11. Turn OFF the Tech 2 and disconnect the Tech
2 from the vehicle. 12. Turn OFF the ignition. 13. Connect the Tech 2 to the Techline terminal. 14.
Select Service Programming. 15. Select Tech 2 as the tool you are using. 16. Select the type of
programming to be performed. 17. Verify the displayed VIN with the vehicle VIN. Correct the VIN
as necessary. 18. Select the type of module you are programming. 19. Identify what type of
programming that you are performing.
^ Normal-This type of programming is for updating an existing calibration or programming a new
controller.
^ Vehicle configuration index (VCI)-This selection is used if the vehicle VIN is unavailable or not
recognized by the Techline terminal. Observe, you will need to contact the Techline Customer
Support center to use this option.
^ Reconfigure-This is to reconfigure a vehicle, such as tire size and axle ratio changes.
20. Select the appropriate calibration file. 21. Ensure all connections are secure. 22. Select Reprog
to initiate the download of the new calibration to the Tech 2. 23. After the download is complete,
turn OFF the Tech 2. 24. Disconnect the Tech 2 from the Techline terminal. 25. Install the Tech 2
to the data link connector (DLC). 26. Turn ON the Tech 2. 27. Turn ON the ignition, with the engine
OFF. 28. Select Service Programming.
IMPORTANT: DO NOT turn OFF the ignition if the programming procedure is interrupted or
unsuccessful. Ensure that all the PCM and DLC
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connections are secure and the Techline(TM) operating software is up to date. Attempt to
reprogram the control module. If the control module cannot be programmed, replace the control
module. Refer to Powertrain Control Module (PCM) Replacement.
29. Select Program. 30. After the download is complete, EXIT Service Programming. 31. Turn OFF
the ignition for 30 seconds. 32. Turn OFF the Tech 2. 33. If a control module is replaced the
following service procedures must be performed:
^ CKP System Variation Learn Procedure
^ Inspection/Maintenance (I/M) Complete System Set Procedure
^ Programming Theft Deterrent System Components
PROGRAMMING VERIFICATION
1. With a scan tool, clear the DTCs. 2. Attempt to start the engine. 3. Repeat the Service
Programming procedure if the engine does not start or operates poorly. Perform the following
procedures before programming
the PCM: ^
Ensure the control module and DLC connections are OK.
^ Ensure the Techline operating software is up to date.
^ Ensure the calibration part number is correct for the vehicle.
4. Attempt to program the control module. If the control module still cannot be programmed
properly, replace the control module. Refer to
Powertrain Control Module (PCM) Replacement. You must program the replacement control
module.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Service and Repair > Powertrain Control Module (PCM) Programming (Off-board) > Page 5458
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Replacement
Service of the powertrain control module (PCM) should normally consist of either replacement of
the PCM or electrically erasable programmable read only memory (EEPROM) programming. If the
diagnostic procedures call for the PCM to be replaced, the PCM should be inspected first to see if
the correct part is being used. If the correct part is being used, remove the faulty PCM and install
the new service PCM.
IMPORTANT: To prevent internal PCM damage, the ignition must be OFF when disconnecting or
reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail,
PCM fuse, or jumper cables. ^
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM
module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are
installed correctly. The gaskets prevent contaminant intrusion into the PCM.
^ The replacement PCM must be programmed
Removal Procedure
1. Release the PCM cover mounting holes (1,5) away from the mounting tabs on the PCM
mounting bracket. 2. Release the PCM cover (8) from the mounting bracket. 3. Remove the PCM
cover.
NOTE: ^
Refer to PCM and ESD Notice in Service Precautions.
^ In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or
reconnecting the PCM connector.
4. Disconnect the PCM harness connectors (6). 5. Release the spring latch (2) from the PCM. 6.
Release the PCM mounting tabs (3) from the PCM. 7. Remove the PCM (4) from the engine
compartment.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Service and Repair > Powertrain Control Module (PCM) Programming (Off-board) > Page 5459
1. Install the PCM (4) to the PCM mounting bracket (7) ensuring that the mounting tabs (3) are
engaged. 2. Secure the spring latch (2) to the PCM.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Connect the PCM connectors (6) to the PCM (4).
Tighten Tighten the PCM connector end fasteners to 8 N.m (71 lb in).
4. Install the PCM cover (8) to the PCM mounting bracket (7), ensuring the mounting tabs on the
PCM mounting bracket are engaged into the
mounting holes in the PCM cover.
5. If a new PCM is being installed, program the PCM. See: Testing and Inspection/Programming
and Relearning
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Service and Repair > Powertrain Control Module (PCM) Programming (Off-board) > Page 5460
Engine Control Module: Service and Repair Service Programming System (SPS)
The Service Programming System (SPS) allows a technician to program a control module through
the Data Link Connector (DLC). The information transfer circuit that is used at the DLC is the same
serial data circuit used by the scan tool for retrieving Diagnostic Trouble Codes (DTCs), displaying
data, clearing DTCs, etc. This procedure offers the ability to install software/calibrations matched to
a particular vehicle.
Most control modules have 2 types of memory. The software/calibrations reside in the flash
memory. The two types of memory are listed below:
^ Electrically Erasable Programmable Read Only Memory (EEPROM)
This type of memory allows selected portions of memory to be programmed while other portions
remain unchanged.
Certain learned values reside in the EEPROM, such as: ^
The Vehicle Identification Number (VIN)
^ The crankshaft variation learned position
^ The software/calibrations identification numbers
^ The control module security information
^ Flash Read Only Memory - Flash Memory
^ Flash memory has increased memory storage capacity. During programming, all information
within this type of memory is erased, and then replaced with entirely new information.
Service Programming Methods The 4 methods of programming a control module and the proper
tools for each method are as follows: ^
Remote Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle
^ Pass Thru Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle.
^ Off-Board Remote Programming, vehicle NOT available: The Tech 2 or other scan tool, Off-board Programming Adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
^ Off-Board Pass Thru Programming -
The Tech 2 or other scan tool, off-board programming adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
Before Programming A Control Module
IMPORTANT: DO NOT program an existing control module with the identical software/calibration
package. This procedure is not a short cut to correct a driveability condition. This is an ineffective
repair. A control module should only be programmed when the following occurs: ^
When a service procedure instructs you to replace the control module. The service part control
module does not contain operating software or calibrations.
^ General Motors Corporation releases an updated software/calibration package.
Ensure that the following conditions are met before programming a control module: ^
Vehicle system voltage: There are no charging system concerns. All charging system concerns must be repaired before
programming a control module.
- The battery voltage is greater than 12 volts but less than 16 volts. The battery must be fully
charged before programming the control module.
- A battery charger is NOT connected to the vehicles battery. Incorrect system voltage or voltage
fluctuations from a battery charger may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicles battery. Turn OFF or disable
systems such as: ^
Daytime Running Lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system.
^ Heating, Ventilation, And Air Conditioning (HVAC) systems
^ Engine cooling fans, etc
^ The ignition switch is in the proper position. The scan tool prompts you to turn ON the ignition,
with the engine OFF. DO NOT change the position of the ignition switch during the programming
procedure unless instructed to do so.
^ All tool connections are secure: The RS-232 cable
- The connection at the DLC
- The voltage supply circuits
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Engine Control Module >
Component Information > Service and Repair > Powertrain Control Module (PCM) Programming (Off-board) > Page 5461
- The OBPA
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
^ If you are performing the pass-through programming procedure using a notebook computer
without the power cord, ensure that the internal battery is fully charged.
After Programming a Control Module The powertrain may operate slightly different after a control
module software/calibration update. Operating the powertrain through various driving conditions
allows the control module to re-learn certain values. The control module must re-learn the following
after a software/calibration update: ^
Fuel trim correction
^ Idle Air Control (IAC) learned position
^ Automatic transmission shift adapts
Other learned values only re-learn by performing a service procedure.
If a control module is replaced the following service procedures may need to be performed: ^
The crankshaft variation learn procedure
^ The engine oil life reset procedure
^ The idle learn procedure
^ The inspection/maintenance complete system set procedure
^ The vehicle theft deterrent password learn procedure
^ The Throttle Position (TP) sensor learn procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Level Sensor >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Level Sensor >
Component Information > Locations > Page 5465
Fuel Level Sensor: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Level Sensor >
Component Information > Locations > Page 5466
Fuel Level Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Tank Pressure Sensor
> Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Tank Pressure Sensor
> Component Information > Locations > Page 5470
Fuel Tank Pressure (FTP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Tank Pressure Sensor
> Component Information > Locations > Page 5471
Fuel Tank Pressure Sensor: Description and Operation
The FTP sensor measures the difference between the pressure or vacuum in the fuel tank and
outside air pressure. The control module provides a 5-volt reference and a ground to the FTP
sensor. The FTP sensor provides a signal voltage back to the control module that can vary
between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low
voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Fuel Tank Pressure Sensor
> Component Information > Locations > Page 5472
Fuel Tank Pressure Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel tank. 2. Remove the fuel pressure sensor (1).
INSTALLATION PROCEDURE
1. Install the fuel pressure sensor (1). 2. Install the fuel tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5476
Idle Air Control (IAC) Valve
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5477
Idle Speed/Throttle Actuator - Electronic: Testing and Inspection
CIRCUIT DESCRIPTION
The engine idle speed is controlled by the idle air control (IAC) valve. The IAC valve is on the
throttle body. The IAC valve pintle moves in and out of an idle air passage bore to control air flow
around the throttle plate. The valve consists of a movable pintle, driven by a gear attached to a two
phase bi-polar permanent magnet electric motor called a stepper motor. The stepper motor is
capable of highly accurate rotation, or of movement, called steps. The stepper motor has two
separate windings that are called coils. Each coil is fed by two circuits from the powertrain control
module (PCM). When the PCM changes polarity of a coil, the stepper motor moves one step. The
PCM uses a predetermined number of counts to determine the IAC pintle position. Observe IAC
counts with a scan tool. The IAC counts will increment up or down as the PCM attempts to change
the IAC valve pintle position. An IAC Reset will occur when the ignition key is turned OFF. First, the
PCM will seat the IAC pintle in the idle air passage bore. Second, the PCM will retract the pintle a
predetermined number of counts to allow for efficient engine start-up. If the engine idle speed is out
of range for a calibrated period of time, an idle speed diagnostic trouble code (DTC) may set.
DIAGNOSTIC AIDS
Inspect for the following conditions: ^
A skewed high throttle position (TP) sensor
^ Restricted air intake system
^ Objects blocking the IAC passage or throttle bore
^ The correct positive crankcase ventilation (PCV) valve
^ A properly installed PCV valve
^ Proper operation of the PCV valve
^ Proper operation and installation of all air intake components
^ Proper installation and operation of the mass air flow (MAF) sensor, if equipped
^ Evidence of damage or tampering of the following components: The throttle stop screw
- The throttle plate
- The throttle shaft
- The throttle linkage
- The cruise control linkage-if equipped
^ Excess deposits in the IAC passage or on the IAC pintle
^ Excess deposits in the throttle bore or on the throttle plate
^ Vacuum leaks
^ Excess load on engine, such as energy-draining conditions of the transmission, power steering,
or alternator
^ A high or unstable idle condition-This condition could be caused by a non-IAC system problem
that can not be overcome by the IAC valve. Refer to Symptoms - Computers and Controls
Systems. See: Testing and Inspection/Symptom Related Diagnostic Procedures
^ A low or unstable idle condition-This condition could be caused by a non-IAC system problem
that can not be overcome by the IAC valve. Refer to Symptoms - Computers and Controls
Systems. See: Testing and Inspection/Symptom Related Diagnostic Procedures
^ An intermittent condition-If the condition is intermittent, refer to Intermittent Conditions. See:
Testing and Inspection/Initial Inspection and Diagnostic Overview/Intermittent Conditions
TEST DESCRIPTION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5478
Steps 1-6
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5479
Steps 7-11
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5480
Steps 12-19
The numbers below refer to the step numbers on the diagnostic table. 5. This test will determine
the ability of the PCM and IAC valve circuits to control the IAC valve. 7. This test will determine the
ability of the PCM to provide the IAC valve circuits with a ground. On a normally operating system,
the test lamp
should not flash while the IAC counts are incrementing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5481
Idle Speed/Throttle Actuator - Electronic: Service and Repair
IDLE AIR CONTROL (IAC) VALVE REPLACEMENT
REMOVAL PROCEDURE
1. Disconnect the idle air control (IAC) valve electrical connector
2. Remove the IAC valve attaching screws (4). 3. Remove the IAC valve (3). 4. Remove the IAC
valve O-ring seal (2).
NOTE: ^
Do Not push or pull on the IAC valve pintle on IAC valves that have been in service. The force
required to move the pintle may damage the threads on the worm drive.
^ Do Not soak the IAC valve in any liquid cleaner or solvent, as damage may result.
5. Clean the IAC valve O-ring sealing surface, the pintle valve seat, and the air passage.
^ Clean the IAC valve using GM cleaner P/N 1052626 or GM X-66A. Use a shop towel or parts
brush to remove heavy deposits.
^ If the air passage has heavy deposits, remove the throttle body for complete cleaning.
^ Shiny spots on the pintle or seat are normal and do not indicate misalignment or a bent pintle
shaft.
6. Inspect the IAC valve O-ring for cuts, cracks, or distortion. Replace the O-ring if the O-ring is
damaged.
INSTALLATION PROCEDURE
IMPORTANT: If installing a new IAC valve, be sure to replace the IAC valve with an identical part.
The pintle shape of the IAC valve and the diameter of the IAC valve are designed for the specific
application.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Idle Speed/Throttle Actuator
- Electronic > Component Information > Locations > Page 5482
1. Measure the distance between the tip of the IAC valve pintle and the mounting surface (1). If the
distance is more than 28 mm (1.1 in) use finger
pressure to slowly retract the pintle. The force required to retract the pintle of a new valve does not
cause damage to the valve.
2. Lubricate the IAC valve O-ring (2) with clean engine oil. 3. Install the IAC valve O-ring (2) on the
IAC valve (3). 4. Install the IAC valve (3). 5. Apply LOCTITE 262 to the IAC valve attaching screw
threads if necessary.
NOTE: Refer to the Fastener Notice in Service Precautions.
6. Install the IAC valve attaching screws (4).
Tighten Tighten the screws to 3 N.m (27 lb in).
7. Connect the IAC valve electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Locations > Data Link Connector (DLC)
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Locations > Data Link Connector (DLC) > Page 5487
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Locations > Page 5488
Information Bus: Diagrams
Splice Pack SP205
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Locations > Page 5489
Data Link Connector (DLC)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Description and Operation > Data Link Communications
Information Bus: Description and Operation Data Link Communications
DATA LINK COMMUNICATIONS CIRCUIT DESCRIPTION AND OPERATION
The Class 2 serial data link allows modules to transmit, receive, or exchange data between each
other: ^
HVAC Control Module (HCM)
^ Rear Wheel Steering Module (RWS)
^ Suspension Control Module (SCM)
^ Active Transfer Case (ATC)
^ Electronic Brake Control Module (EBCM)
^ Powertrain Control Module (PCM)
^ Transmission Control Module (TCM)
^ OnStar(R) Module (ONS)
^ Body Control Module (BCM)
^ Instrument Panel Cluster (IPC)
^ Driver Information Center (DIC)
^ Mirror Memory Module (MMM)
^ Memory Seat Module (MSM)
^ Inflatable Restraint Sensing And Diagnostic Module (SDM)
CIRCUIT DESCRIPTION
Modules connected to the class 2 serial data circuit monitor for serial data communications during
normal vehicle operation. Operating information and commands are exchanged among the
modules. In addition to this, Node Alive messages are transmitted by each module on the class 2
serial data circuit about once every 2 seconds. When the module detects the class 2 serial data
circuit shorted, the setting of all other class 2 serial communication DTCs is inhibited and a U1300,
U1301, or a U1305 DTC will set.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Description and Operation > Data Link Communications > Page 5492
Information Bus: Description and Operation General Description
DATA LINK COMMUNICATIONS CIRCUIT DESCRIPTION AND OPERATION
The Class 2 serial data link allows modules to transmit, receive, or exchange data between each
other: ^
HVAC Control Module (HCM)
^ Rear Wheel Steering Module (RWS)
^ Suspension Control Module (SCM)
^ Active Transfer Case (ATC)
^ Electronic Brake Control Module (EBCM)
^ Powertrain Control Module (PCM)
^ Transmission Control Module (TCM)
^ OnStar(R) Module (ONS)
^ Body Control Module (BCM)
^ Instrument Panel Cluster (IPC)
^ Driver Information Center (DIC)
^ Mirror Memory Module (MMM)
^ Memory Seat Module (MSM)
^ Inflatable Restraint Sensing And Diagnostic Module (SDM)
CIRCUIT DESCRIPTION
Modules connected to the class 2 serial data circuit monitor for serial data communications during
normal vehicle operation. Operating information and commands are exchanged among the
modules. In addition to this, Node Alive messages are transmitted by each module on the class 2
serial data circuit about once every 2 seconds. When the module detects the class 2 serial data
circuit shorted, the setting of all other class 2 serial communication DTCs is inhibited and a U1300,
U1301, or a U1305 DTC will set.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview
Information Bus: Initial Inspection and Diagnostic Overview
Begin the diagnosis of the Data Link Communications by performing the Diagnostic System Check
for the system in which the customer concern is apparent.
The Diagnostic System Check will direct you to the correct procedure within the Data Link
Communications when a communication malfunction is present.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 5495
Information Bus: Symptom Related Diagnostic Procedures
A Symptoms - Data Link Communications
IMPORTANT: The following steps must be completed before using the symptom tables:
1. Perform the Diagnostic System Check for the subsystem exhibiting the symptoms. The
subsystem diagnostic system check will identify where to
begin diagnosis of the data link communication system.
2. Review the system operation in order to familiarize yourself with the system functions. Refer to
Data Link Communications Description and
Operation.
Visual/Physical Inspection ^
Inspect for aftermarket devices that could affect the operation of the serial data communications
systems. Refer to Checking Aftermarket Accessories in Diagnostic Aids.
^ Inspect the easily accessible systems or visible system components for obvious damage or
conditions that could cause the symptom.
Intermittent Faulty electrical connections or wiring may be the cause of intermittent conditions.
Refer to Testing for Intermittent and Poor Connections in Diagnostic Aids.
Symptom List Refer to a symptom diagnostic procedure from the following list in order to diagnose
the symptom: ^
Scan Tool Does Not Power Up
^ Scan Tool Does Not Communicate with Class 2 Device
Scan Tool Does Not Communicate With Class 2 Device
CIRCUIT DESCRIPTION
Modules connected to the class 2 serial data circuit monitor for serial data communications during
normal vehicle operation. Operating information and commands are exchanged among the
modules. Connecting a scan tool to the DLC allows communication with the modules for diagnostic
purposes. DTCs may be set due to this symptom and during this diagnostic procedure. Complete
the diagnostic procedure in order to ensure all the DTCs are diagnosed and cleared from memory.
DIAGNOSTIC AIDS
^ The BCM detects that the ignition is ON and sends the appropriate power mode message to the
other modules. Therefore, the BCM must be connected to the DLC for any other module to
communicate with the scan tool.
^ When the class 2 serial data circuit: ^
is shorted to ground
^ is shorted to voltage
The following DTCs may set: ^
U1300
^ U1301
^ U1305
TEST DESCRIPTION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 5496
Steps 1-4
Steps 5-10
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 5497
Steps 11-18
The numbers below refer to the step numbers on the diagnostic table. 2. A partial loss of
communication in the class 2 serial data circuit uses a different procedure than a total loss of
communication of the class 2 serial
data circuit.
4. The following DTCs may be retrieved with a history status. These DTCs are not the cause of the
present condition.
^ U1300
^ U1301
^ U1305
6. A State of Health DTC with a history status may be present along with a U1000 or U1255 with a
current status. This indicates that the malfunction
occurred when the ignition was on.
10. Normal class 2 serial data communication cannot take place until the power mode master
(PMM) module sends the appropriate power mode
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Information Bus >
Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 5498
message. If the PMM does not send a wake-up message, other modules on the class 2 serial data
circuit may not communicate.
15. If there are no current DTCs that begin with the letter "U", the communication concern has been
repaired. 16. The communication concern may have prevented diagnosis of the customer
complaint.
Scan Tool Does Not Power Up
CIRCUIT DESCRIPTION
The data link connector (DLC) is a standardized 16 cavity connector. Connector design and
location is dictated by an industry wide standard, and is required to provide the following: ^
Scan tool power battery positive voltage at terminal 16.
^ Scan tool power ground at terminal 4.
^ Common signal ground at terminal 5.
The scan tool will power up with the ignition off. Some modules however, will not communicate
unless the ignition is on and the power mode master (PMM) module sends the appropriate power
mode message.
TEST DESCRIPTION
Steps 1-4
The number below refers to the step number on the diagnostic table. 4. If the battery positive
voltage and ground circuits of the DLC are functioning properly. The malfunction must be due to
the scan tool.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5507
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5508
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 >
Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 >
Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5514
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 >
Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 5515
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Technical Service Bulletins > Page 5516
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information > Diagrams > Diagram Information and Instructions > Page 5519
Electrical Symbols Part 1
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Information > Diagrams > Diagram Information and Instructions > Page 5520
Electrical Symbols Part 2
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Electrical Symbols Part 3
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Information > Diagrams > Diagram Information and Instructions > Page 5522
Electrical Symbols Part 4
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Information > Diagrams > Diagram Information and Instructions > Page 5523
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Information > Diagrams > Diagram Information and Instructions > Page 5524
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Information > Diagrams > Diagram Information and Instructions > Page 5525
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Information > Diagrams > Diagram Information and Instructions > Page 5526
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5529
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5531
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information > Diagrams > Diagram Information and Instructions > Page 5532
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5533
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5534
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5535
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5537
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5540
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5541
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5542
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5543
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5545
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5546
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5547
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5548
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 5549
Knock Sensor (KS)
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
Information > Diagrams > Page 5550
Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Knock Sensor > Component
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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Information > Diagrams > Page 5552
1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Malfunction Indicator Lamp >
Component Information > Testing and Inspection > Malfunction Indicator Lamp (MIL) Always On
Malfunction Indicator Lamp: Testing and Inspection Malfunction Indicator Lamp (MIL) Always On
CIRCUIT DESCRIPTION
Battery positive voltage is supplied directly to the malfunction indicator lamp (MIL). The powertrain
control module (PCM) turns the MIL ON by grounding the MIL control circuit.
MIL OPERATION
The MIL is located on the instrument panel (IP).
MIL FUNCTION
^ The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for
service as soon as possible.
^ The MIL illuminates during a bulb test and a system test.
^ A DTC will be stored if a MIL is requested by the diagnostic.
MIL ILLUMINATION
^ The MIL will illuminate with ignition switch ON and the engine not running.
^ The MIL will turn OFF when the engine is started.
^ The MIL will remain ON if the self-diagnostic system has detected a malfunction.
^ The MIL may turn OFF if the malfunction is not present.
^ If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so long as the
ignition switch is ON.
^ If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition
switch is cycled OFF, then ON.
DIAGNOSTIC AIDS
If the problem is intermittent, refer to Intermittent Conditions. See: Testing and Inspection/Initial
Inspection and Diagnostic Overview/Intermittent Conditions
TEST DESCRIPTION
Steps 1-6
The number below refers to the step numbers on the diagnostic table. 2. The step determines if the
condition is with the MIL control circuit or the PCM.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Malfunction Indicator Lamp >
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Malfunction Indicator Lamp: Testing and Inspection Malfunction Indicator Lamp (MIL) Inoperative
CIRCUIT DESCRIPTION
Battery positive voltage is supplied directly to the malfunction indicator lamp (MIL). The powertrain
control module (PCM) turns the MIL ON by grounding the MIL control circuit. There should be a
steady MIL with the ignition ON and the engine OFF.
MIL OPERATION
The MIL is located on the instrument panel (IP).
MIL FUNCTION
^ The MIL informs the driver that a malfunction has occurred and the vehicle should be taken in for
service as soon as possible.
^ The MIL illuminates during a bulb test and a system test.
^ A DTC will be stored if a MIL is requested by the diagnostic.
MIL ILLUMINATION
^ The MIL will illuminate with ignition switch ON and the engine not running.
^ The MIL will turn OFF when the engine is started.
^ The MIL will remain ON if the self-diagnostic system has detected a malfunction.
^ The MIL may turn OFF if the malfunction is not present.
^ If the MIL is illuminated and then the engine stalls, the MIL will remain illuminated so long as the
ignition switch is ON.
^ If the MIL is not illuminated and the engine stalls, the MIL will not illuminate until the ignition
switch is cycled OFF, then ON.
DIAGNOSTIC AIDS
If the problem is intermittent, refer to Intermittent Conditions. See: Testing and Inspection/Initial
Inspection and Diagnostic Overview/Intermittent Conditions
TEST DESCRIPTION
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Steps 1-14
The numbers below refer to the step numbers on the diagnostic table. 3. This step determines if the
condition is with the MIL control circuit or the PCM. 4. This step determines if a voltage is being
applied to the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Manifold Pressure/Vacuum
Sensor > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Manifold Pressure/Vacuum
Sensor > Component Information > Locations > Page 5562
Manifold Absolute Pressure (MAP) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Manifold Pressure/Vacuum
Sensor > Component Information > Locations > Page 5563
Manifold Pressure/Vacuum Sensor: Service and Repair
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield. 2. Disconnect the manifold absolute pressure (MAP) sensor
electrical connector.
3. Remove the MAP sensor (1) from the intake manifold.
INSTALLATION PROCEDURE
IMPORTANT: Lightly coat the MAP sensor seal with clean engine oil before installing the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Sensor > Component Information > Locations > Page 5564
1. Install the MAP sensor (1). Push the MAP sensor down in order to engage the sensor into the
retainer.
2. Connect the MAP sensor electrical connector. 3. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oil Level Sensor For ECM >
Component Information > Diagrams
Engine Oil Level Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions
Oxygen Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 5573
Electrical Symbols Part 1
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Component Information > Diagrams > Diagram Information and Instructions > Page 5574
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5575
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5576
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5577
Oxygen Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Component Information > Diagrams > Diagram Information and Instructions > Page 5578
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Component Information > Diagrams > Diagram Information and Instructions > Page 5588
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5589
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5596
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5597
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5598
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5599
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5600
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5601
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5602
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5603
Oxygen Sensor: Connector Views
Delphi
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Delphi)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Delphi)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5604
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Delphi)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Delphi)
Denso
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5605
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Denso)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Denso)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 5606
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Denso)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Denso)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Diagrams > Page 5607
Oxygen Sensor: Description and Operation
HEATED OXYGEN SENSORS
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases. The PCM uses the
signal voltage from the fuel control HO2S in a Closed Loop in order to adjust the fuel injector pulse
width. While in a Closed Loop, the PCM can adjust fuel delivery in order to maintain an air to fuel
ratio which allows the best combination of emission control and driveability.
If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5610
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5611
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5612
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5613
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5614
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5615
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Oxygen Sensor >
Component Information > Service and Repair > Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page
5616
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions
Body Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5623
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5624
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5625
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5626
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5627
Body Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5628
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5629
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Instructions > Page 5641
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Instructions > Page 5642
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Instructions > Page 5643
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Instructions > Page 5644
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Instructions > Page 5645
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5646
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5647
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Instructions > Page 5648
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Instructions > Page 5649
Equivalents - Decimal And Metric Part 1
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Instructions > Page 5650
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5651
Various symbols are used in order to describe different service operations.
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Instructions > Page 5652
Conversion - English/Metric
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5653
Body Control Module: Connector Views
Body Control Module Connector (BCM) - C1
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5654
Body Control Module (BCM) - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5655
Body Control Module (BCM) - C3
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5656
Body Control Module: Electrical Diagrams
Controlled/Monitored Subsystem References
Controlled/Monitored Subsystem References
Body Control Module Schematics: Controlled/Monitored Subsystem References
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5657
Exterior Lighting Systems References
Exterior Lighting Systems References
Body Control Module Schematics: Exterior Lighting Systems References
Interior Lighting Systems References
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Diagrams > Diagram Information and
Instructions > Page 5658
Interior Lighting Systems References
Body Control Module Schematics: Interior Lighting Systems References
Power, Ground and Serial Data
Power, Ground and Serial Data
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Instructions > Page 5659
Body Control Module Schematics: Power, Ground And Serial Data
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Body Control Module > Component Information > Service and Repair > Procedures
Body Control Module: Procedures
IMPORTANT: If any module is replaced, programming the module with the proper RPO
configurations must be done prior to performing the Passlock Learn procedure.
1. The BCM must be programmed with the proper RPO configurations. The BCM stores the
information regarding the vehicle options. If the BCM is
not properly configured with the correct RPO codes the BCM will not control the features properly.
Ensure that the following conditions exist in order to prepare for BCM programming: ^
The battery is fully charged.
^ The ignition switch is in the RUN position.
^ The DLC is accessible.
^ All disconnected modules and devices are reconnected before programming.
2. Follow the SPS instructions on the Techline Terminal and scan tool to program the BCM. 3. If
the BCM fails to accept the program, perform the following steps:
^ Inspect all BCM connections.
^ Verify that the SPS Techline Terminal and scan tool have the latest software version.
Passlock Learn Procedures Refer to the Theft Deterrent sub-system for the appropriate learn
procedure.
IMPORTANT: After programming, perform the following to avoid future misdiagnosis: 1. Turn the
ignition OFF for 10 seconds. 2. Connect the scan tool to the data link connector. 3. Turn the ignition
ON with the engine OFF. 4. Use the scan tool in order to retrieve History DTCs from all modules. 5.
Clear all history DTCs.
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Page 5662
Body Control Module: Removal and Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Cautions and Notices.
1. Disconnect the negative battery cable(s). 2. Remove the knee bolster.
3. Disconnect the brown connector. 4. Disconnect all other connectors (1). 5. Remove the BCM
from the sliding bracket.
INSTALLATION PROCEDURE
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Page 5663
1. Slide the BCM onto the bracket. 2. Connect all the connectors (1) except the brown connector. 3.
Connect the brown connector.
4. Install the knee bolster. 5. Connect the negative battery cable(s). 6. Reprogram the BCM.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Electronic Throttle Control Module > Component Information > Locations
Electronic Throttle Control Module: Locations
Locations View
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Locations View
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Electronic Throttle Control Module: Diagrams
Throttle Actuator Control (TAC) Module Connector C1
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Throttle Actuator Control (TAC) Module Connector C2
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Electronic Throttle Control Module: Description and Operation
THROTTLE ACTUATOR CONTROL (TAC) MODULE
Throttle Actuator Control (TAC) Module
The TAC module is the control center for the electronic throttle system. The TAC module and the
powertrain control module (PCM) communicate via a dedicated redundant serial data circuit. The
TAC module and the PCM monitor the commanded throttle position and compare the commanded
position to the actual throttle position. This is accomplished by monitoring the APP and the TP
sensor. These 2 values must be within a calibrated value of each other. The TAC module also
monitors each individual circuit of the TP sensor and the APP to verify proper operation.
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Electronic Throttle Control Module: Service and Repair
THROTTLE ACTUATOR CONTROL (TAC) MODULE REPLACEMENT
REMOVAL PROCEDURE
1. Release the retainer tab from the left side of the throttle actuator control (TAC) module. 2. Slowly
slide the TAC module out of the retaining bracket. 3. Disconnect the TAC module connectors from
the TAC module.
INSTALLATION PROCEDURE
1. Connect the TAC module connectors to the TAC module. 2. Slide the TAC module into the TAC
module bracket. 3. Push the TAC module towards the bracket in order to snap the TAC module into
the bracket.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins >
Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Engine Control Module: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins >
Customer Interest: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL ON/Misfire/Misfire DTC's Set > Page 5680
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket
Accessory Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket
Accessory Usage > Page 5686
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set
Engine Control Module: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire
DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
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Technical Service Bulletins for Engine Control Module: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set > Page 5691
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
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Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket Accessory
Usage
Engine Control Module: All Technical Service Bulletins Engine Controls - Aftermarket Accessory
Usage
INFORMATION
Bulletin No.: 04-06-04-054B
Date: November 18, 2010
Subject: Info - Non-GM Parts and Accessories (Aftermarket)
Models:
2011 and Prior GM Passenger Cars and Trucks
Supercede: This bulletin is being revised to add model years and update to the new U.S. Fixed
Operation Manager (FOM) and Canada Warranty Manager (WM) names. Please discard Corporate
Bulletin Number 04-06-04-054A (Section 06 - Engine/Propulsion System).
The recent rise and expansion of companies selling non-GM parts and accessories has made it
necessary to issue this reminder to dealers regarding GM's policy on the use and installation of
these aftermarket components.
When a dealer is performing a repair under the New Vehicle Limited Warranty, they are required to
use only genuine GM or GM-approved parts and accessories. This applies to all warranty repairs,
special policy repairs or any repairs paid for by GM. Parts and accessories advertised as being "the
same" as parts manufactured by GM, but not sold through GM, do not qualify for use in warranty
repairs, special policy repairs or any repairs paid for by GM.
During a warranty repair, if a GM original equipment part is not available through GM Customer
Care and Aftersales (GM CC&A;), ACDelco(R) distributors, other GM dealers or approved sources,
the dealer is to obtain comparable, non-GM parts and clearly indicate, in detail, on the repair order
the circumstances surrounding why non-GM parts were used. The dealer must give customers
written notice, prior to the sale or service, that such parts or accessories are not marketed or
warranted by General Motors.
It should also be noted that dealers modifying new vehicles and installing equipment, parts and
accessories obtained from sources not authorized by GM are responsible for complying with the
National Traffic and Motor Vehicle Safety Act. Certain non-approved parts or assemblies, installed
by the dealer or its agent not authorized by GM, may result in a change to the vehicle's design
characteristics and may affect the vehicle's ability to conform to federal law. Dealers must fully
understand that non-GM approved parts may not have been validated, tested or certified for use.
This puts the dealer at risk for potential liability in the event of a part or vehicle failure. If a GM part
failure occurs as the result of the installation or use of a non-GM approved part, the warranty will
not be honored.
A good example of non-authorized modification of vehicles is the result of an ever increasing
supply of aftermarket devices available to the customer, which claim to increase the horsepower
and torque of the Duramax(TM) Diesel Engines. These include the addition of, but are not limited to
one or more of the following modifications:
- Propane injection
- Nitrous oxide injection
- Additional modules (black boxes) that connect to the vehicle wiring systems
- Revised engine calibrations downloaded for the engine control module
- Calibration modules which connect to the vehicle diagnostic connector
- Modification to the engine turbocharger waste gate
Although the installation of these devices, or modification of vehicle components, can increase
engine horsepower and torque, they may also negatively affect the engine emissions, reliability
and/or durability. In addition, other powertrain components, such as transmissions, universal joints,
drive shafts, and front/rear axle components, can be stressed beyond design safety limits by the
installation of these devices.
General Motors does not support or endorse the use of devices or modifications that, when
installed, increase the engine horsepower and torque. It is because of these unknown stresses,
and the potential to alter reliability, durability and emissions performance, that GM has adopted a
policy that prevents any UNAUTHORIZED dealer warranty claim submissions to any remaining
warranty coverage, to the powertrain and driveline components whenever the presence of a
non-GM (aftermarket) calibration is confirmed - even if the non-GM control module calibration is
subsequently removed. Refer to the latest version of Bulletin 09-06-04-026 (V8 Gas Engines) or
06-06-01-007 (Duramax(TM) Diesel Engines) for more information on dealer requirements for
calibration verification.
These same policies apply as they relate to the use of non-GM accessories. Damage or failure
from the use or installation of a non-GM accessory will not be covered under warranty. Failure
resulting from the alteration or modification of the vehicle, including the cutting, welding or
disconnecting of the vehicle's original equipment parts and components will void the warranty.
Additionally, dealers will NOT be reimbursed or compensated by GM in the event of any legal
inquiry at either the local, state or federal level that
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Technical Service Bulletins > All
Other Service Bulletins for Engine Control Module: > 04-06-04-054B > Nov > 10 > Engine Controls - Aftermarket Accessory
Usage > Page 5697
results from the alteration or modification of a vehicle using non-GM approved parts or accessories.
Dealers should be especially cautious of accessory companies that claim the installation of their
product will not void the factory warranty. Many times these companies have even given direction
on how to quickly disassemble the accessory in an attempt to preclude the manufacturer from
finding out that is has been installed.
Any suspect repairs should be reviewed by the Fixed Operations Manager (FOM), and in Canada
by the Warranty Manager (WM) for appropriate repair direction. If it is decided that a goodwill repair
is to be made on the vehicle, even with the installation of such non-GM approved components, the
customer is to be made aware of General Motors position on this issue and is to sign the
appropriate goodwill documentation required by General Motors.
It is imperative for dealers to understand that by installing such devices, they are jeopardizing not
only the warranty coverage, but also the performance and reliability of the customer's vehicle.
Disclaimer
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5698
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Diagrams > Diagram Information
and Instructions
Engine Control Module: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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and Instructions > Page 5701
Electrical Symbols Part 1
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and Instructions > Page 5702
Electrical Symbols Part 2
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and Instructions > Page 5703
Electrical Symbols Part 3
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and Instructions > Page 5704
Electrical Symbols Part 4
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and Instructions > Page 5705
Engine Control Module: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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and Instructions > Page 5706
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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and Instructions > Page 5709
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Engine Control Module: Connector Views
Powertrain Control Module (PCM) C1 Part 1
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Powertrain Control Module (PCM) C1 Part 2
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Powertrain Control Module (PCM) C1 Part 3
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Powertrain Control Module (PCM) C2 Part 1
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Powertrain Control Module (PCM) C2 Part 2
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Powertrain Control Module (PCM) C2 Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Relays and Modules Computers and Control Systems > Engine Control Module > Component Information > Description and Operation >
Electronic Ignition (EI) System Description
Engine Control Module: Description and Operation Electronic Ignition (EI) System Description
POWERTRAIN CONTROL MODULE (PCM)
The PCM controls all ignition system functions, and constantly corrects the basic spark timing. The
PCM monitors information from various sensor inputs that include the following:
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Mass Airflow (MAF) sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Vehicle Speed Sensor (VSS)
^ The transmission gear position or range information sensors
^ The Engine Knock Sensors (KS)
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Electronic Ignition (EI) System Description > Page 5739
Engine Control Module: Description and Operation Powertrain Control Module (PCM) Description
General Information
The Powertrain Control Module (PCM) is designed to maintain exhaust emission levels while
maintaining excellent driveability and fuel efficiency. The PCM controls the following operations:
^ The fuel control
^ The Ignition Control (IC)
^ The Knock Sensor (KS) system
^ The automatic transmission shift functions
^ The manual transmission
^ The cruise control enable, if equipped
^ The generator
^ The evaporative emissions (EVAP) purge
^ The A/C clutch control, if equipped
^ The secondary air injection (AIR), if equipped
^ The Exhaust Gas Recirculation (EGR)
PCM Function
The PCM supplies a buffered voltage to various sensors and switches. The PCM controls most
components with electronic switches which complete a ground circuit when turned ON.
Powertrain Control Module
Powertrain Control Module
The Powertrain Control Module (PCM) is located in the engine compartment. The PCM is the
control center of the vehicle. The PCM controls the following:
^ The fuel metering system
^ The transmission shifting
^ The ignition timing
^ The on-board diagnostics for powertrain functions
The PCM constantly monitors the information from various sensors and controls the systems that
affect vehicle performance and emissions. The PCM also performs the diagnostic functions for
those systems. The PCM can recognize operational problems and alert the driver through the
Malfunction Indicator Lamp (MIL) when a malfunction has occurred. When a malfunction is
detected, the PCM stores a Diagnostic Trouble Code (DTC) which helps to identify problem areas.
This is done to aid the technician in making repairs.
The PCM supplies either 5.0 or 12.0 volts to power various sensors and switches. This is done
through resistances in the PCM. The resistance is so high in value that a test lamp does not
illuminate when connected to the circuit. In some cases, even an ordinary shop voltmeter does not
give an accurate reading because the voltmeters resistance is too low. Therefore, a DMM with a
minimum of 10 megaohms input impedance is required to ensure accurate voltage readings.
The PCM controls output circuits such as the fuel injectors, the Idle Air Control (IAC), the cooling
fan relays, etc. by controlling the ground or the power feed circuit through transistors or a device
called an output driver module.
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Electronic Ignition (EI) System Description > Page 5740
Torque Management
Torque management is a function of the PCM that reduces engine power under certain conditions.
Torque management is performed for the following reasons:
1. To prevent over-stressing the powertrain and driveline components 2. To prevent damage to the
vehicle during certain abusive maneuvers 3. To reduce engine speed when the IAC is out of the
normal operating range
The PCM monitors the following sensors and engine parameters in order to calculate engine output
torque:
^ The air/fuel ratio
^ The Mass Air Flow (MAF) sensor
^ The Manifold Absolute Pressure (MAP) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The spark advance
^ The engine speed
^ The Engine Coolant Temperature (ECT) Sensor
^ The A/C clutch status
The PCM monitors the torque converter status, the transmission gear ratio, and the engine speed
in order to determine if torque reduction is required. The PCM retards the spark as appropriate to
reduce engine torque output if torque reduction is required. The PCM also shuts OFF the fuel to
certain injectors in order to reduce the engine power in the case of an abusive maneuver.
The following are instances when engine power reduction is likely to be experienced:
^ During transmission upshifts and downshifts
^ During heavy acceleration from a standing start
^ When the clutch pedal is released too quick under a heavy load, 6.0L only
^ When one set of drive axles looses traction while the other set of drive axles are not moving, 4
Wheel Drive only and in 4WD low
^ If the IAC is out of the normal operating range, except 6.0L
^ When the driver is performing harsh or abusive maneuvers such as shifting into gear at high
throttle angles or shifting the transmission from reverse to drive to create a rocking motion
The driver is unlikely to notice the torque management actions in the first 2 instances. The engine
power output is moderate at full throttle in the other cases.
The PCM calculates the amount of spark retard necessary to reduce the engine power by the
desired amount. The PCM disables the fuel injectors for cylinders 1, 4, 6, and 7 in the case of an
abusive maneuver.
Basic Knowledge Required
Without a basic knowledge of electricity, you will have difficulty using the diagnostic procedures.
You should understand the basic theory of electricity and know the meaning of voltage-volts,
current-amps, and resistance-ohms. You should understand what happens in a circuit with an open
or a shorted wire. You should be able to read and understand a wiring diagram.
PCM Service Precautions
The PCM is designed to withstand normal current draws associated with vehicle operations. Avoid
overloading any circuit. When testing for opens or shorts, do not ground any of the PCM circuits
unless instructed. When testing for opens or shorts, do not apply voltage to any of the PCM circuits
unless instructed. Only test these circuits with a DMM while the PCM connectors remain
connected.
Engine Controls Information
The driveability and emissions information describes the function and operation of the powertrain
control module (PCM).
The engine controls Information contains the following:
^ Component locations
^ Wiring diagrams
^ PCM terminal end view and terminal definitions
^ Diagnostic System Check-Computers and Controls Systems
^ Diagnostic trouble code (DTC) tables
The component system includes the following items:
^ Component and circuit description
^ On-vehicle service for each sub-system
^ Functional checks and diagnostic tables
The DTCs also contain diagnostic support information containing circuit diagrams, circuit or system
information, and helpful diagnostic information.
System Status and Drive Cycle For Inspection/Maintenance
The System Status selection is included in the scan tool System Info menu.
Several states require that the I/M (OBD II system) pass on-board tests for the major diagnostics
prior to having a vehicle emission inspection. This is
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also a requirement to renew license plates in some areas.
Using a scan tool, the technician can observe the System Status, complete or not complete, in
order to verify that the vehicle meets the criteria to comply with local area requirements. Using the
System Status display, any of the following systems or combination of systems may be monitored
for I/M Readiness:
^ The catalyst
^ The Evaporative Emission (EVAP) system
^ The Heated Oxygen Sensors (HO2S)
^ The HO2S heater
^ The Exhaust Gas Recirculation (EGR) system
^ The secondary air injection (AIR) system
IMPORTANT: The System Status display indicates only whether or not the test has been
completed. The System Status display does not necessarily mean that the test has passed. If a
Failed Last Test indication is present for a DTC associated with one of the above systems,
diagnosis and repair is necessary in order to meet the I/M requirement. Verify that the vehicle
passes all of the diagnostic tests associated with the displayed System Status prior to returning the
vehicle to the customer. Refer to the Typical Drive Cycle table, more than one drive cycle may be
needed, to use as a guide to complete the I/M System Status tests.
Typical Drive Cycle
Following a DTC info clear, System Status clears for one or all of these systems. Following a
battery disconnect or a PCM replacement, all System Status information clears.
Primary System Based Diagnostics
There are primary system-based diagnostics which evaluate the system operation and their effect
on vehicle emissions. The primary system-based diagnostics are listed below, with a brief
description of the diagnostic functionality.
Oxygen Sensor Diagnosis
Diagnose the fuel control heated oxygen sensors (HO2S) for the following conditions:
^ Heater performance, heater current monitor
^ Response switches, number or switches R/L or L/R
^ Response time, time to switch R/L or L/R
^ Inactive signal, output steady at bias voltage - approximately 450 mV
^ Signal fixed high
^ Signal fixed low
Diagnose the catalyst monitor HO2S for the following functions:
^ Heater performance, heater current monitor
^ Signal fixed low
^ Signal fixed high
^ Inactive sensor
Heated Oxygen Sensors
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases.
The PCM uses the signal voltage from the fuel control HO2S in a Closed Loop in order to adjust
the fuel injector pulse width. While in a Closed Loop, the PCM can adjust fuel delivery in order to
maintain an air to fuel ratio which allows the best combination of emission control and driveability.
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If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Catalyst Monitor Heated Oxygen Sensors
In order to control emissions of HydroCarbons (HC), Carbon Monoxide (CO), and Oxides Of
Nitrogen (NOx), the system uses a TWC. The catalyst promotes a chemical reaction which oxidizes
the HC and CO present in the exhaust gas, converting the HC and CO into harmless water vapor
and carbon dioxide. The catalyst also converts NOx to nitrogen. Catalyst monitor HO2S,
post-catalyst HO2S, are always located downstream of the catalytic converter.
The PCM has the ability to monitor this process using the post catalyst HO2S. The pre-sensors
produce an output signal which indicates the amount of oxygen present in the exhaust gas entering
the TWC. The post sensor produces an output signal which indicates the oxygen storage capacity
of the catalyst. This in turn indicates the catalysts ability to convert exhaust gases efficiently. If the
catalyst is operating efficiently, the pre-HO2S signal is far more active than that produced by the
post-HO2S.
In addition to catalyst monitoring, the post-HO2S has a limited role in controlling fuel delivery. If the
post-HO2S signal indicates a high or low oxygen content for an extended period of time while in a
Closed Loop, the PCM adjusts the fuel delivery slightly in order to compensate.
Catalyst Monitor Diagnostic Operation
The catalyst monitor diagnostic measures oxygen storage capacity of the catalyst converter. In
order to do this, the HO2S are installed before and after the TWC. Voltage variations between the
sensors allow the PCM to determine the catalyst emission performance.
As a catalyst becomes less effective in promoting chemical reactions, the catalysts capacity to
store and release oxygen generally degrades. The catalyst monitor diagnostic is based on a
correlation between conversion efficiency and oxygen storage capacity.
A good catalyst, e.g. 95 percent hydrocarbon conversion efficiency, shows a relatively flat output
voltage on the post-catalyst HO2S. A degraded catalyst, 65 percent hydrocarbon conversion,
shows a greatly increased activity in output voltage from the post catalyst HO2S.
The post-catalyst HO2S is used to measure the oxygen storage and release capacity of the
catalyst. A high oxygen storage capacity indicates a good catalyst. Low oxygen storage capacity
indicates a failing catalyst. The TWC and the HO2S must be at operating temperature in order to
achieve correct oxygen sensor voltages like those shown in the post-catalyst HO2S outputs
graphic.
The catalyst monitor diagnostic is sensitive to the following conditions:
^ Exhaust leaks
^ HO2S contamination
^ Alternative fuels
Exhaust system leaks may cause the following:
^ Prevent a degraded catalyst from failing the diagnostic
^ Cause a false failure for a normally functioning catalyst
^ Prevent the diagnostic from running
Some of the contaminants that may be encountered are phosphorus, lead, silica, and sulfur. The
presence of these contaminants prevent the TWC diagnostic from functioning properly.
Three-Way Catalyst Oxygen Storage Capacity
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Electronic Ignition (EI) System Description > Page 5743
Three-Way Catalyst Oxygen Storage Capacity
The PCM must monitor the TWC system for efficiency. In order to accomplish this, the PCM
monitors the pre-catalyst and post-catalyst HO2S. When the TWC is operating properly, the
post-catalyst (2) HO2S shows significantly less activity than the pre-catalyst (1) HO2S. The TWC
stores oxygen during the normal reduction and oxidation process. The TWC releases oxygen
during the normal reduction and oxidation process. The PCM calculates the oxygen storage
capacity using the difference between the pre-catalyst and post-catalyst HO2S voltage levels.
Whenever the sensor activity of the post-catalyst (2) HO2S nears the sensor activity of the
pre-catalyst (1) HO2S, the catalysts efficiency is degraded. Aftermarket HO2S characteristics may
be different from the original equipment manufacturer sensor. This may lead to a false pass or a
false fail of the catalyst monitor diagnostic. Similarly, if an aftermarket catalyst does not contain the
same amount of precious metal content as the original part, the correlation between oxygen
storage and conversion efficiency may be altered enough to set a false DTC.
Misfire Monitor Diagnostic Operation
The misfire monitor diagnostic is based on crankshaft rotational velocity, aka reference period,
variations. The PCM determines crankshaft rotational velocity using the Crankshaft Position (CKP)
Sensor and Camshaft Position (CMP) Sensor. When a cylinder misfires, the crankshaft slows down
momentarily. By monitoring the crankshaft and CMP sensor signals, the PCM can calculate when a
misfire occurs.
For a non-catalyst damaging misfire, the diagnostic is required to monitor a misfire present for
between 1,000-3,200 engine revolutions.
For catalyst damage misfire, the diagnostic responds to the misfire within 200 engine revolutions
Rough roads may cause false misfire detection. A rough road applies sudden torque variations to
the drive wheels and drivetrain. This torque can intermittently decrease the crankshaft rotational
velocity. The Antilock Braking (ABS) System detects uneven speed between the vehicles wheels
and sends data via the serial data bus to the PCM to disable the misfire monitor until the rough
road is no longer detected.
On automatic transmission equipped vehicles, the Torque Converter Clutch (TCC) disables
whenever a misfire is detected. Disabling the TCC isolates the engine from the rest of the drive line
and minimizes the affect of the drive wheel inputs on crankshaft rotation.
When the TCC has disabled as a result of misfire detection, the TCC is re-enabled after
approximately 3,200 engine revolutions if no misfire is detected. The TCC remains disabled
whenever the misfire is detected, with or without a DTC set. This allows the misfire diagnostic to
reevaluate the system.
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Whenever a cylinder misfires, the misfire diagnostic counts the misfire and notes the crankshaft
position at the time the misfire occurred.
A current and a history misfire counter is maintained for each cylinder. The misfire current
counters, Misfire Cur #1-8, indicate the number of firing events out of the last 200 cylinder firing
events which were misfires. The misfire current counters displays real time data without a misfire
DTC stored. The misfire history counters, Misfire Hist #1-8, indicate the total number of cylinder
firing events which were misfires. The misfire history counters display 0 until the misfire diagnostic
has failed and a DTC P0300 is set. Once the misfire DTC sets, the misfire history counters will be
updated every 200 cylinder firing events. The Misfire counters graphic illustrates how these misfire
counters are maintained.
When crankshaft rotation is erratic, the PCM detects a misfire condition. Because of this erratic
condition, the data that is collected by the diagnostic can sometimes incorrectly identify which
cylinder is misfiring. The Misfire Counters graphic shows there are misfires counted from more than
one cylinder. Cylinder #1 has the majority of counted misfires. In this case, the misfire counters
would identify cylinder #1 as the misfiring cylinder. The misfires in the other counters were just
background noise caused by the erratic rotation of the crankshaft. If the number of accumulated
misfires is sufficient for the diagnostic to identify a true misfire, the diagnostic will set DTC
P0300-Misfire Detected. The illustration depicts an accumulation in the history buffers.
If two cylinders in sequential tiring order are both misfiring, the first misfiring cylinder will
accumulate misfires in the cylinder buffer, but the second misfiring cylinder will not. This is because
the PCM compares a misfiring cylinder with the cylinder 90 degrees prior to that cylinder in the
firing order. Therefore the PCM would be comparing crankshaft speed of the second misfiring
cylinder to an already suspect cylinder. The PCM however, will be able to detect both misfiring
cylinders after the engine exceeds 2,000 RPM. This is because the PCM then starts to compare
misfires to the opposing cylinder rather than the previous cylinder in the firing order.
Use Techline equipment to monitor the misfire counter data on applicable vehicles. Knowing which
specific cylinders misfire can lead to the root cause. Using the information in the misfire counters
identifies which cylinders are misfiring. If the counters indicate cylinders number 1 and 4 misfired,
look for a circuit or component common to both cylinders.
The misfire diagnostic may indicate a fault due to a temporary fault not necessarily caused by a
vehicle emission system malfunction. Examples include the following items:
^ Contaminated fuel
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Electronic Ignition (EI) System Description > Page 5745
^ Running out of fuel
^ Fuel fouled spark plugs
^ Basic engine fault
Fuel Trim System Operation
The fuel trim system monitors the averages of short-term and long-term fuel trim values. If these
fuel trim values stay at the individual limits for a calibrated period of time, a malfunction is indicated.
The fuel trim diagnostic compares the average of short and long-term fuel trim values. If either
value is within the thresholds, a pass is recorded. If either value is outside the thresholds, a rich or
lean fuel trim DTC will set.
Comprehensive Component Monitor Diagnostic
Comprehensive component monitoring diagnostics are required to monitor emissions-related input
and output powertrain components.
Input Components The PCM monitors the input components for circuit continuity and out-of-range
values. This includes performance checking. Performance checking refers to indicating a fault
when the signal from a sensor does not seem reasonable, such as a Throttle Position (TP) sensor
that indicates high throttle position at low engine loads or manifold Absolute Pressure (MAP)
Voltage. The input components may include, but are not limited to, the following sensors: ^
The Vehicle Speed (VSS) Sensor
^ The Mass Air Flow (MAF) Sensor
^ The Intake Air Temperature (IAT) Sensor
^ The Crankshaft Position (CKP) Sensor
^ The Knock Sensor (KS)
^ The Throttle Position (TP) Sensor
^ The Engine Coolant Temperature (ECT) Sensor
^ The Camshaft Position (CMP) Sensor
^ The Manifold Absolute Pressure (MAP) Sensor
In addition to the circuit continuity and rationality check, the engine coolant temperature (ECT)
sensor is monitored for the sensors ability to achieve a steady state temperature to enable Closed
Loop fuel control.
Output Components Diagnose the output components for the proper response to PCM commands.
Components where functional monitoring is not feasible will be monitored for circuit continuity and
out-of-range values if applicable.
Output components to be monitored include, but are not limited to, the following circuits: ^
The Idle Air Control (IAC) Motor
^ The Evaporative Emission (EVAP) System
^ The electronic transmission controls
^ The A/C relay, if equipped
^ The VSS output
^ The Malfunction Indicator Lamp (MIL) Control
^ The cruise control enable, if equipped
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Control Module (PCM) Programming (Off-board)
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(Off-board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: ^
DO NOT program a control module unless you are directed by a service procedure or you are
directed by a General Motors Corporation service bulletin. Programming a control module at any
other time will not permanently correct a customer's concern.
^ The Off-Board Programming is used in situations where a control module must be programmed
without having the vehicle present. The Off-Board Programming Adapter must be used to perform
the Off-Board Programming procedure. The adapter allows the control module to power up and
allows the Tech 2 to communicate with the control module.
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
Ensure that all connections are secure at the following locations: ^
The Off-Board Programming Adapter
^ The Tech 2
^ The control module
^ The Techline terminal
OFF-BOARD PROGRAMMING
1. Obtain the VIN of the vehicle for which the control module is being programmed. 2. With the
Techline terminal, select Service Programming. 3. Select Tech 2, Reprogram ECU, and Off-Board
Programming Adapter as the ECU location. 4. Connect the control module, Off-Board
Programming Adapter, and the Tech 2 as described on the Techline terminal. Ensure you use the
correct
harness connector from the Off-Board Programming Adapter kit.
5. With the Tech 2, select Service Programming Request Information function. The Tech 2
communicates with the control module and receives the
access code.
6. With the Tech 2, exit the Service Programming Request Information. 7. Disconnect the Tech 2
from the Off-Board Programming Adapter. 8. Connect the Tech 2 to the Techline terminal. 9. Turn
ON the Tech 2.
10. With the Techline terminal, enter the VIN of the vehicle that will be receiving the control module.
11. The Techline terminal will display the message, attaching to database. 12. Identify what type of
programming that you are performing. 13. Select the appropriate calibration file. 14. Ensure all
connections are secure. 15. The Techline terminal displays a summary screen that summarizes
your selections. After confirming you choices, the Techline terminal
automatically loads the calibration files to the Tech 2.
16. After the download is complete, turn OFF the Tech 2. 17. Disconnect the Tech 2 from the
Techline terminal. 18. Connect the Tech 2 to the Off-Board Programming Adapter. 19. With the
Tech 2, select Service Programming.
IMPORTANT: DO NOT turn OFF the Off-Board Programming Adapter if the programming
procedure is interrupted or unsuccessful. Ensure the control module and the Off-Board
Programming Adapter connections are secure and the Techline operating software is up to date.
Attempt to reprogram the control module. If the control module cannot be programmed, replace the
control module.
20. With the Tech 2, select Program. 21. After the download is complete, exit Service
Programming. 22. Turn OFF the Off-Board Programming Adapter.
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Control Module (PCM) Programming (Off-board) > Page 5748
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Programming
(On-Board)
BEFORE PROGRAMMING A CONTROL MODULE
IMPORTANT: DO NOT program a control module unless you are directed by a service procedure
or you are directed by a General Motors Corporation service bulletin. Programming a control
module at any other time will not permanently correct a customers concern.
Ensure the following conditions are met before programming a control module: ^
Vehicle system voltage There is no charging system concern. All charging system concerns must be repaired before
programming a control module.
- Battery voltage is greater than 12 volts but less than 16 volts. The battery must be charged before
programming the control module if the battery voltage is low.
- A battery charger is NOT connected to the vehicle's battery. Incorrect system voltage or voltage
fluctuations from a battery charger, may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicle's battery. ^
Twilight sentinel
^ Interior lights
^ Daytime running lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system. Refer to the Owners manual.
^ HVAC systems
^ Cooling System fans, etc.
^ The ignition is in the proper position. The scan tool prompts you to turn ON the ignition, with the
engine OFF. DO NOT change the position of the ignition switch during the programming procedure,
unless instructed to do so.
^ All tool connections are secure. RS-232
- The connection at the DLC is secure.
- Voltage supply circuits
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
REMOTE PROGRAMMING
1. Turn OFF the ignition. 2. Install the Tech 2 to the data link connector (DLC). 3. Turn ON the
ignition, with the engine OFF. 4. Turn OFF all vehicle accessories. 5. With the Tech 2, select
Service Programming. 6. Identify vehicle information as requested by the Tech 2. 7. Select the type
of module you are programming. 8. Select the type of programming to be performed. 9. Verify the
displayed VIN with the vehicle VIN. If the displayed VIN does not match the actual VIN, write down
the actual VIN and correct the
VIN at the Techline terminal.
10. When complete, Exit Service Programming. 11. Turn OFF the Tech 2 and disconnect the Tech
2 from the vehicle. 12. Turn OFF the ignition. 13. Connect the Tech 2 to the Techline terminal. 14.
Select Service Programming. 15. Select Tech 2 as the tool you are using. 16. Select the type of
programming to be performed. 17. Verify the displayed VIN with the vehicle VIN. Correct the VIN
as necessary. 18. Select the type of module you are programming. 19. Identify what type of
programming that you are performing.
^ Normal-This type of programming is for updating an existing calibration or programming a new
controller.
^ Vehicle configuration index (VCI)-This selection is used if the vehicle VIN is unavailable or not
recognized by the Techline terminal. Observe, you will need to contact the Techline Customer
Support center to use this option.
^ Reconfigure-This is to reconfigure a vehicle, such as tire size and axle ratio changes.
20. Select the appropriate calibration file. 21. Ensure all connections are secure. 22. Select Reprog
to initiate the download of the new calibration to the Tech 2. 23. After the download is complete,
turn OFF the Tech 2. 24. Disconnect the Tech 2 from the Techline terminal. 25. Install the Tech 2
to the data link connector (DLC). 26. Turn ON the Tech 2. 27. Turn ON the ignition, with the engine
OFF. 28. Select Service Programming.
IMPORTANT: DO NOT turn OFF the ignition if the programming procedure is interrupted or
unsuccessful. Ensure that all the PCM and DLC
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Control Module (PCM) Programming (Off-board) > Page 5749
connections are secure and the Techline(TM) operating software is up to date. Attempt to
reprogram the control module. If the control module cannot be programmed, replace the control
module. Refer to Powertrain Control Module (PCM) Replacement.
29. Select Program. 30. After the download is complete, EXIT Service Programming. 31. Turn OFF
the ignition for 30 seconds. 32. Turn OFF the Tech 2. 33. If a control module is replaced the
following service procedures must be performed:
^ CKP System Variation Learn Procedure
^ Inspection/Maintenance (I/M) Complete System Set Procedure
^ Programming Theft Deterrent System Components
PROGRAMMING VERIFICATION
1. With a scan tool, clear the DTCs. 2. Attempt to start the engine. 3. Repeat the Service
Programming procedure if the engine does not start or operates poorly. Perform the following
procedures before programming
the PCM: ^
Ensure the control module and DLC connections are OK.
^ Ensure the Techline operating software is up to date.
^ Ensure the calibration part number is correct for the vehicle.
4. Attempt to program the control module. If the control module still cannot be programmed
properly, replace the control module. Refer to
Powertrain Control Module (PCM) Replacement. You must program the replacement control
module.
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Control Module (PCM) Programming (Off-board) > Page 5750
Engine Control Module: Service and Repair Powertrain Control Module (PCM) Replacement
Service of the powertrain control module (PCM) should normally consist of either replacement of
the PCM or electrically erasable programmable read only memory (EEPROM) programming. If the
diagnostic procedures call for the PCM to be replaced, the PCM should be inspected first to see if
the correct part is being used. If the correct part is being used, remove the faulty PCM and install
the new service PCM.
IMPORTANT: To prevent internal PCM damage, the ignition must be OFF when disconnecting or
reconnecting power to the PCM. For example, when working with a battery cable, PCM pigtail,
PCM fuse, or jumper cables. ^
Remove any debris from the PCM connector surfaces before servicing the PCM. Inspect the PCM
module connector gaskets when diagnosing or replacing the PCM. Ensure that the gaskets are
installed correctly. The gaskets prevent contaminant intrusion into the PCM.
^ The replacement PCM must be programmed
Removal Procedure
1. Release the PCM cover mounting holes (1,5) away from the mounting tabs on the PCM
mounting bracket. 2. Release the PCM cover (8) from the mounting bracket. 3. Remove the PCM
cover.
NOTE: ^
Refer to PCM and ESD Notice in Service Precautions.
^ In order to prevent internal damage to the PCM, the ignition must be OFF when disconnecting or
reconnecting the PCM connector.
4. Disconnect the PCM harness connectors (6). 5. Release the spring latch (2) from the PCM. 6.
Release the PCM mounting tabs (3) from the PCM. 7. Remove the PCM (4) from the engine
compartment.
Installation Procedure
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Control Module (PCM) Programming (Off-board) > Page 5751
1. Install the PCM (4) to the PCM mounting bracket (7) ensuring that the mounting tabs (3) are
engaged. 2. Secure the spring latch (2) to the PCM.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Connect the PCM connectors (6) to the PCM (4).
Tighten Tighten the PCM connector end fasteners to 8 N.m (71 lb in).
4. Install the PCM cover (8) to the PCM mounting bracket (7), ensuring the mounting tabs on the
PCM mounting bracket are engaged into the
mounting holes in the PCM cover.
5. If a new PCM is being installed, program the PCM. See: Testing and Inspection/Programming
and Relearning
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Control Module (PCM) Programming (Off-board) > Page 5752
Engine Control Module: Service and Repair Service Programming System (SPS)
The Service Programming System (SPS) allows a technician to program a control module through
the Data Link Connector (DLC). The information transfer circuit that is used at the DLC is the same
serial data circuit used by the scan tool for retrieving Diagnostic Trouble Codes (DTCs), displaying
data, clearing DTCs, etc. This procedure offers the ability to install software/calibrations matched to
a particular vehicle.
Most control modules have 2 types of memory. The software/calibrations reside in the flash
memory. The two types of memory are listed below:
^ Electrically Erasable Programmable Read Only Memory (EEPROM)
This type of memory allows selected portions of memory to be programmed while other portions
remain unchanged.
Certain learned values reside in the EEPROM, such as: ^
The Vehicle Identification Number (VIN)
^ The crankshaft variation learned position
^ The software/calibrations identification numbers
^ The control module security information
^ Flash Read Only Memory - Flash Memory
^ Flash memory has increased memory storage capacity. During programming, all information
within this type of memory is erased, and then replaced with entirely new information.
Service Programming Methods The 4 methods of programming a control module and the proper
tools for each method are as follows: ^
Remote Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle
^ Pass Thru Programming: The Tech 2 or other scan tool, Techline Terminal or a personal computer equipped with General
Motors Corporation authorized programming software-The Tech 2 or other scan tool is used as an
interface between the vehicle and the Techline Terminal or a personal computer.
- The control module is installed in the vehicle.
^ Off-Board Remote Programming, vehicle NOT available: The Tech 2 or other scan tool, Off-board Programming Adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
^ Off-Board Pass Thru Programming -
The Tech 2 or other scan tool, off-board programming adapter (OBPA), Techline Terminal or a
personal computer equipped with General Motors Corporation authorized programming
software-The Tech 2 or other scan tool is used as an interface between the vehicle and the
Techline Terminal or a personal computer.
- The control module is NOT installed in a vehicle
Before Programming A Control Module
IMPORTANT: DO NOT program an existing control module with the identical software/calibration
package. This procedure is not a short cut to correct a driveability condition. This is an ineffective
repair. A control module should only be programmed when the following occurs: ^
When a service procedure instructs you to replace the control module. The service part control
module does not contain operating software or calibrations.
^ General Motors Corporation releases an updated software/calibration package.
Ensure that the following conditions are met before programming a control module: ^
Vehicle system voltage: There are no charging system concerns. All charging system concerns must be repaired before
programming a control module.
- The battery voltage is greater than 12 volts but less than 16 volts. The battery must be fully
charged before programming the control module.
- A battery charger is NOT connected to the vehicles battery. Incorrect system voltage or voltage
fluctuations from a battery charger may cause programming failure or control module damage.
- Turn OFF or disable any system that may put a load on the vehicles battery. Turn OFF or disable
systems such as: ^
Daytime Running Lights (DRL). Applying the parking brake, on most vehicles, disables the DRL
system.
^ Heating, Ventilation, And Air Conditioning (HVAC) systems
^ Engine cooling fans, etc
^ The ignition switch is in the proper position. The scan tool prompts you to turn ON the ignition,
with the engine OFF. DO NOT change the position of the ignition switch during the programming
procedure unless instructed to do so.
^ All tool connections are secure: The RS-232 cable
- The connection at the DLC
- The voltage supply circuits
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Control Module (PCM) Programming (Off-board) > Page 5753
- The OBPA
^ DO NOT disturb the tool harnesses while programming. If an interruption occurs during the
programming procedure, programming failure or control module damage may occur.
^ If you are performing the pass-through programming procedure using a notebook computer
without the power cord, ensure that the internal battery is fully charged.
After Programming a Control Module The powertrain may operate slightly different after a control
module software/calibration update. Operating the powertrain through various driving conditions
allows the control module to re-learn certain values. The control module must re-learn the following
after a software/calibration update: ^
Fuel trim correction
^ Idle Air Control (IAC) learned position
^ Automatic transmission shift adapts
Other learned values only re-learn by performing a service procedure.
If a control module is replaced the following service procedures may need to be performed: ^
The crankshaft variation learn procedure
^ The engine oil life reset procedure
^ The idle learn procedure
^ The inspection/maintenance complete system set procedure
^ The vehicle theft deterrent password learn procedure
^ The Throttle Position (TP) sensor learn procedure
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Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Accelerator Pedal Position Sensor > Component Information > Locations > Page 5758
Accelerator Pedal Position (APP) Sensor
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Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Air Flow Meter/Sensor > Component Information > Locations
Locations View
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Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Instructions > Page 5767
Electrical Symbols Part 1
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Electrical Symbols Part 2
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Instructions > Page 5769
Electrical Symbols Part 3
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Instructions > Page 5770
Electrical Symbols Part 4
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Instructions > Page 5771
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Instructions > Page 5784
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Instructions > Page 5785
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Instructions > Page 5786
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Instructions > Page 5787
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Instructions > Page 5788
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Instructions > Page 5789
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Instructions > Page 5790
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Instructions > Page 5791
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Instructions > Page 5792
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Instructions > Page 5793
Equivalents - Decimal And Metric Part 1
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Instructions > Page 5794
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Instructions > Page 5795
Various symbols are used in order to describe different service operations.
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Instructions > Page 5796
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Instructions > Page 5797
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Camshaft Position Sensor > Component Information > Locations
Locations View
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and Instructions
Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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and Instructions > Page 5805
Electrical Symbols Part 1
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Electrical Symbols Part 2
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and Instructions > Page 5807
Electrical Symbols Part 3
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Electrical Symbols Part 4
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and Instructions > Page 5809
Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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and Instructions > Page 5822
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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and Instructions > Page 5823
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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and Instructions > Page 5824
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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and Instructions > Page 5827
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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and Instructions > Page 5828
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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and Instructions > Page 5832
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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and Instructions > Page 5833
Various symbols are used in order to describe different service operations.
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and Instructions > Page 5834
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Camshaft Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 5835
Camshaft Position (CMP) Sensor
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Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Coolant Temperature Sensor/Switch (For Computer) > Component Information >
Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Coolant Temperature Sensor/Switch (For Computer) > Component Information >
Locations > Page 5841
Engine Coolant Temperature (ECT) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Coolant Temperature Sensor/Switch (For Computer): Service and Repair
ENGINE COOLANT TEMPERATURE (ECT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
NOTE: Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
1. Turn OFF the ignition. 2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.. 3. Drain the
cooling system below the level of the ECT sensor. Refer to Draining and Filling Cooling System in
Cooling System. 4. Lower the vehicle. 5. Disconnect the electrical connector from the engine
coolant temperature (ECT) sensor.
6. Remove the ECT sensor.
INSTALLATION PROCEDURE
NOTE: ^
Replacement components must be the correct part number for the application. Components
requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are
identified in the service procedure. Some replacement components may come with these coatings
already applied. Do not use these coatings on components unless specified. These coatings can
affect the final torque, which may affect the operation of the component. Use the correct torque
specification when installing components in order to avoid damage.
^ Use care when handling the coolant sensor. Damage to the coolant sensor will affect the
operation of the fuel control system.
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1. Coat the ECT sensor threads with sealer GM P/N 12346004 or the equivalent.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ECT sensor.
Tighten Tighten the ECT sensor to 20 N.m (15 lb ft).
3. Connect the ECT sensor electrical connector. 4. Refill the engine coolant. Refer to Draining and
Filling Cooling System in Cooling System.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Crankshaft Position Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Crankshaft Position Sensor > Component Information > Diagrams > Diagram
Information and Instructions
Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information and Instructions > Page 5849
Electrical Symbols Part 1
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Electrical Symbols Part 2
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Information and Instructions > Page 5851
Electrical Symbols Part 3
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Information and Instructions > Page 5852
Electrical Symbols Part 4
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Information and Instructions > Page 5853
Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Information and Instructions > Page 5865
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Information and Instructions > Page 5867
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Information and Instructions > Page 5870
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information and Instructions > Page 5879
Crankshaft Position (CKP) Sensor
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Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Crankshaft Position Sensor > Component Information > Service and Repair > CKP
System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
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Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
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5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
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3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Fuel Level Sensor > Component Information > Locations
Locations View
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Fuel Level Sensor: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
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Fuel Level Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page 5894
Fuel Tank Pressure (FTP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page 5895
Fuel Tank Pressure Sensor: Description and Operation
The FTP sensor measures the difference between the pressure or vacuum in the fuel tank and
outside air pressure. The control module provides a 5-volt reference and a ground to the FTP
sensor. The FTP sensor provides a signal voltage back to the control module that can vary
between 0.1-4.9 volts. As FTP increases, FTP sensor voltage decreases, high pressure = low
voltage. As FTP decreases, FTP voltage increases, low pressure or vacuum = high voltage.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Fuel Tank Pressure Sensor > Component Information > Locations > Page 5896
Fuel Tank Pressure Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel tank. 2. Remove the fuel pressure sensor (1).
INSTALLATION PROCEDURE
1. Install the fuel pressure sensor (1). 2. Install the fuel tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Intake Air Temperature Sensor > Component Information > Locations > Page 5900
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Intake Air Temperature Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Customer
Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Customer
Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
5911
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Customer
Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page
5912
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All Technical
Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All Technical
Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
> Page 5918
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > All Technical
Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
> Page 5919
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Technical Service Bulletins > Page 5920
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information and
Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5923
Electrical Symbols Part 1
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Instructions > Page 5924
Electrical Symbols Part 2
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Instructions > Page 5925
Electrical Symbols Part 3
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Instructions > Page 5926
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Knock Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5927
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Instructions > Page 5928
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Instructions > Page 5929
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Instructions > Page 5930
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Instructions > Page 5931
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Instructions > Page 5939
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Instructions > Page 5944
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Instructions > Page 5945
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Instructions > Page 5947
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Instructions > Page 5951
Various symbols are used in order to describe different service operations.
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Instructions > Page 5952
Conversion - English/Metric
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Instructions > Page 5953
Knock Sensor (KS)
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Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Manifold Pressure/Vacuum Sensor > Component Information > Locations
Locations View
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Manifold Absolute Pressure (MAP) Sensor
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Manifold Pressure/Vacuum Sensor: Service and Repair
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield. 2. Disconnect the manifold absolute pressure (MAP) sensor
electrical connector.
3. Remove the MAP sensor (1) from the intake manifold.
INSTALLATION PROCEDURE
IMPORTANT: Lightly coat the MAP sensor seal with clean engine oil before installing the sensor.
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1. Install the MAP sensor (1). Push the MAP sensor down in order to engage the sensor into the
retainer.
2. Connect the MAP sensor electrical connector. 3. Install the engine sight shield.
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Engine Oil Level Switch
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Locations
Locations View
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Instructions
Oxygen Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Oxygen Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5991
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5992
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5993
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5994
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5995
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5996
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5997
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5998
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 5999
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6000
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6001
Oxygen Sensor: Connector Views
Delphi
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Delphi)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Delphi)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6002
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Delphi)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Delphi)
Denso
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6003
Heated Oxygen Sensor (H02S) Bank 1 Sensor 2 (Denso)
Heated Oxygen Sensor (H02S) Bank 1 Sensor 1 (Denso)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6004
Heated Oxygen Sensor (H02S) Bank 2 Sensor 1 (Denso)
Heated Oxygen Sensor (H02S) Bank 2 Sensor 2 (Denso)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Diagrams > Page 6005
Oxygen Sensor: Description and Operation
HEATED OXYGEN SENSORS
The main function of the pre-catalyst HO2S is to provide the PCM with exhaust stream information
in order to maintain proper fueling to hold emissions within acceptable levels. These oxygen
sensors are always located between the exhaust manifold and the 3-way Catalytic Converter
(TWC). After the sensor reaches the operating temperature, the sensor generates a voltage
inversely proportional to the amount of oxygen present in the exhaust gases. The PCM uses the
signal voltage from the fuel control HO2S in a Closed Loop in order to adjust the fuel injector pulse
width. While in a Closed Loop, the PCM can adjust fuel delivery in order to maintain an air to fuel
ratio which allows the best combination of emission control and driveability.
If the HO2S pigtail wiring, connector, or terminal are damaged, replace the entire HO2S assembly.
Do not attempt to repair the wiring, the connector, or the terminals. In order for the sensor to
function properly, the sensor must be provided with a clean air reference. This clean air reference
is obtained by way of the HO2S wires. Any attempt to repair the wires, connectors, or terminals
could result in the obstruction of the air reference. Any attempt to repair the wires, connectors, or
terminals could degrade HO2S performance.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6008
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6009
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 1 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6010
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6011
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
1
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6012
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6013
Oxygen Sensor: Service and Repair Heated Oxygen Sensor (HO2S) Replacement Bank 2 Sensor
2
TOOLS REQUIRED
J 39194-B Oxygen Sensor Wrench
REMOVAL PROCEDURE
CAUTION: Refer to Vehicle Lifting Caution in Service Precautions.
1. Raise the vehicle.
NOTE: Refer to Heated Oxygen and Oxygen Sensor Notice in Service Precautions.
2. Disconnect the connector (1) for the HO2S.
NOTE: Refer to Excessive Force and Oxygen Sensor Notice in Service Precautions.
3. Remove the HO2S (2) using a J 39194-B.
INSTALLATION PROCEDURE
IMPORTANT: A special anti-seize compound is used on the heated oxygen sensor (HO2S)
threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn
away, but the glass beads remain, making the sensor easier to remove. New, or service
replacement sensors already have the compound applied to the threads. If the sensor is removed
from an engine and if for any reason the sensor is to be reinstalled, the threads must have
anti-seize compound applied before the reinstallation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Oxygen Sensor > Component Information > Service and Repair > Heated Oxygen
Sensor (HO2S) Replacement Bank 1 Sensor 1 > Page 6014
1. Coat the threads of the oxygen sensor with anti-seize compound GM P/N 5613695, if necessary.
NOTE: Refer to Component Fastener Tightening Notice in Service Precautions.
2. Install the HO2S (2) using a J 39194-B.
Tighten Tighten the sensor to 42 N.m (31 lb ft).
3. Connect the HO2S harness connector (1). 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions
Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 6020
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 6021
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 6022
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 6023
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Throttle Position Sensor > Component Information > Diagrams > Diagram Information
and Instructions > Page 6024
Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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and Instructions > Page 6049
Conversion - English/Metric
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and Instructions > Page 6050
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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4L60-E
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4L60-E > Page 6059
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4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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4L60-E > Page 6062
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information > Service and
Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Repair > 4L60-E > Page 6065
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Sensors and Switches Computers and Control Systems > Transmission Position Switch/Sensor, A/T > Component Information > Service and
Repair > 4L60-E > Page 6066
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Repair > 4L60-E > Page 6067
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Locations
Locations View
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Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Component Information > Diagrams > Diagram Information and Instructions > Page 6073
Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6076
Electrical Symbols Part 4
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Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Component Information > Diagrams > Diagram Information and Instructions > Page 6089
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6101
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6102
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6103
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Page 6104
Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Page 6105
4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Throttle Position Sensor >
Component Information > Diagrams > Page 6106
4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 6112
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E > Page 6115
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 6118
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 6119
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Computers and Control Systems > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 6120
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair
Catalytic Converter: Service and Repair
Catalytic Converter Replacement (4.81- and 5.31- Engines)
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information. 2. Remove the engine shield bolts and shield, if necessary.
3. Remove the oil pan skid plate bolts and plate, if necessary.
4. Unclip the oxygen sensor connection from the floor reinforcement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair > Page 6125
5. Remove the clip from around the engine harness and the oxygen sensor pigtail. 6. Disconnect
the connector position assurance (CPA) retainers. 7. Disconnect the oxygen sensor electrical
connectors.
8. Unclip the oxygen sensors electrical connectors from the following:
- Hose clip
- Transmission crossmember
9. Disconnect the CPA retainers.
10. Disconnect the oxygen sensor electrical connectors (1, 2).
11. Remove the left exhaust manifold pipe nuts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair > Page 6126
12. Remove the right exhaust manifold pipe nuts.
13. Remove the exhaust muffler nuts. 14. Remove the catalytic converter.
15. Remove the oxygen sensors if the catalytic converter is to be replaced.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair > Page 6127
Notice: Refer to Fastener Notice in Cautions and Notices.
1. If the catalytic converter was replaced, perform the following:
1.1. Apply anti-seize compound GM P/N 12377953 or equivalent to the threads of the old oxygen
sensors.
1.2. Install the oxygen sensors.
- Tighten the oxygen sensors to 42 Nm (31 ft. lbs.).
2. Install the catalytic convertor.
3. Install NEW exhaust manifold pipe seals to the exhaust manifolds. 4. Install the right exhaust
manifold pipe nuts until sung.
5. Install the left exhaust manifold pipe nuts until snug. 6. Tighten the right and left exhaust
manifold pipe nuts.
- Tighten the nuts to 50 Nm (39 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair > Page 6128
7. Install the exhaust muffler nuts.
- Tighten the nuts to 40 Nm (30 ft. lbs.).
8. Connect the oxygen sensor electrical connectors (1, 2). 9. Connect the CPA retainers.
10. Clip the oxygen sensors electrical connectors to the following:
- Hose clip
- Transmission crossmember
11. Connect the oxygen sensor electrical connectors. 12. Connect the CPA retainers. 13. Install the
clip around the engine harness and the oxygen sensor pigtail.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Catalytic Converter > Component
Information > Service and Repair > Page 6129
14. Clip the oxygen sensor connection to the floor reinforcement.
15. Install the oil pan skid plate and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.)
16. Install the engine shield and bolts, if necessary.
- Tighten the bolts to 20 Nm (15 ft. lbs.).
17. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Control Valve > Component Information > Description and Operation
Canister Purge Control Valve: Description and Operation
EVAP PURGE VALVE
The EVAP purge valve controls the flow of vapors from the EVAP system to the intake manifold.
This normally closed valve is Pulse Width Modulated (PWM) by the control module to precisely
control the flow of fuel vapor to the engine. The valve will also be opened during some portions of
the EVAP testing, allowing engine vacuum to enter the EVAP system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Control Valve > Component Information > Description and Operation > Page 6134
Canister Purge Control Valve: Service and Repair
EVAPORATIVE EMISSION (EVAP) CANISTER PURGE VALVE REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield.
2. Push the evaporative emission (EVAP) pipe quick connect fitting retainer inward.
3. Disconnect the EVAP pipe (2) from the EVAP purge solenoid (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Control Valve > Component Information > Description and Operation > Page 6135
4. Disconnect the EVAP purge solenoid electrical connector. 5. Remove the EVAP purge solenoid
mount bolt (2). 6. Remove the EVAP purge solenoid (3) and the insulator (1) from the engine.
INSTALLATION PROCEDURE
1. Install the insulator (1) on the EVAP canister purge valve (3). 2. Install the EVAP canister purge
valve (3) to the engine.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the EVAP canister purge valve mount bolt (2).
Tighten Tighten the EVAP canister purge valve mount bolt to 10.5 N.m (93 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Control Valve > Component Information > Description and Operation > Page 6136
4. Connect the EVAP pipe (2) to the EVAP canister purge valve (1). 5. Connect the EVAP canister
purge valve electrical connector.
6. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Solenoid > Component Information > Diagrams
Evaporative Emission (EVAP) Canister Purge Solenoid
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Canister Purge Solenoid > Component Information > Diagrams > Page 6140
Canister Purge Solenoid: Description and Operation
EVAP Vent Valve
The EVAP vent valve controls fresh airflow into the EVAP canister. The valve is normally open. The
control module will command the valve closed during some EVAP tests, allowing the system to be
tested for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins >
Customer Interest for Canister Vent Valve: > 04-06-04-055A > Mar > 06 > Emissions - SES Lamp ON/DTC P0446 (EVAP)
Set
Canister Vent Valve: Customer Interest Emissions - SES Lamp ON/DTC P0446 (EVAP) Set
Bulletin No.: 04-06-04-055A
Date: March 20, 2006
TECHNICAL
Subject: LR4, LM4, LM7, L59, LQ9, LQ4, L18 DTC P0446 (Restricted/Blocked EVAP Vent Path)
Set, Service Engine Soon (SES) Lamp Illuminated (Replace Vent Solenoid and Bracket)
Models: 2000-2003 Cadillac Escalade 2002-2003 Cadillac Escalade EXT 2003 Cadillac Escalade
ESV 2000-2003 Chevrolet Suburban, Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC
Yukon, Yukon XL
with 4.8L, 5.3L, 6.0L, 8.1L Vortec(TM) V8 Engine (VINs V, P, T, Z, N, U, G - RPOs LR4, LM4, LM7,
L59, LQ9, LQ4, L18)
Supercede:
This bulletin is being revised to add updated warranty information and enhance the content. Please
discard Corporate Bulletin Number 04-06-04-055 (Section 06 - Engine/Propulsion System).
Condition
Some customers whose vehicles are operated in dusty type environments, such as farming or
mining off-road type applications, may comment about the illumination of the instrument panel SES
light, with a DTC of P0446 (Restricted/Blocked EVAP Vent Path) being set.
Cause
Dirt and dust intrusion into the EVAP canister vent solenoid, resulting in restricted air flow, may
cause this condition.
Correction
After following the Service Manual diagnostic P0446 and determining that the EVAP canister vent
valve is the cause of the SES light, replace the existing EVAP canister vent solenoid and bracket.
This new vent solenoid has an enhanced filtering capability and a filter element that can be easily
removed and cleaned. To ensure correct installation, follow the procedure below.
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information.
2. Remove the bolt retaining the vent valve bracket.
3. Disconnect the electrical connector.
4. Disconnect the canister vent valve hose.
5. Install the new vent valve bracket, P/N 15105605, to the vehicle with the retaining bolt.
Tighten
Tighten the bracket mounting bolt to 12 N.m (106 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins >
Customer Interest for Canister Vent Valve: > 04-06-04-055A > Mar > 06 > Emissions - SES Lamp ON/DTC P0446 (EVAP)
Set > Page 6150
6. Install the new vent valve, P/N 10382105, to the bracket.
7. Reinstall the electrical connector.
8. Reinstall the canister vent valve hose.
9. Lower the vehicle.
10. Clear the DTC.
Parts Information
Warranty Information
For vehicles repaired under warranty, use
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Canister Vent Valve: > 04-06-04-055A > Mar > 06 > Emissions - SES Lamp ON/DTC P0446
(EVAP) Set
Canister Vent Valve: All Technical Service Bulletins Emissions - SES Lamp ON/DTC P0446
(EVAP) Set
Bulletin No.: 04-06-04-055A
Date: March 20, 2006
TECHNICAL
Subject: LR4, LM4, LM7, L59, LQ9, LQ4, L18 DTC P0446 (Restricted/Blocked EVAP Vent Path)
Set, Service Engine Soon (SES) Lamp Illuminated (Replace Vent Solenoid and Bracket)
Models: 2000-2003 Cadillac Escalade 2002-2003 Cadillac Escalade EXT 2003 Cadillac Escalade
ESV 2000-2003 Chevrolet Suburban, Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC
Yukon, Yukon XL
with 4.8L, 5.3L, 6.0L, 8.1L Vortec(TM) V8 Engine (VINs V, P, T, Z, N, U, G - RPOs LR4, LM4, LM7,
L59, LQ9, LQ4, L18)
Supercede:
This bulletin is being revised to add updated warranty information and enhance the content. Please
discard Corporate Bulletin Number 04-06-04-055 (Section 06 - Engine/Propulsion System).
Condition
Some customers whose vehicles are operated in dusty type environments, such as farming or
mining off-road type applications, may comment about the illumination of the instrument panel SES
light, with a DTC of P0446 (Restricted/Blocked EVAP Vent Path) being set.
Cause
Dirt and dust intrusion into the EVAP canister vent solenoid, resulting in restricted air flow, may
cause this condition.
Correction
After following the Service Manual diagnostic P0446 and determining that the EVAP canister vent
valve is the cause of the SES light, replace the existing EVAP canister vent solenoid and bracket.
This new vent solenoid has an enhanced filtering capability and a filter element that can be easily
removed and cleaned. To ensure correct installation, follow the procedure below.
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General
Information.
2. Remove the bolt retaining the vent valve bracket.
3. Disconnect the electrical connector.
4. Disconnect the canister vent valve hose.
5. Install the new vent valve bracket, P/N 15105605, to the vehicle with the retaining bolt.
Tighten
Tighten the bracket mounting bolt to 12 N.m (106 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins > All
Technical Service Bulletins for Canister Vent Valve: > 04-06-04-055A > Mar > 06 > Emissions - SES Lamp ON/DTC P0446
(EVAP) Set > Page 6156
6. Install the new vent valve, P/N 10382105, to the bracket.
7. Reinstall the electrical connector.
8. Reinstall the canister vent valve hose.
9. Lower the vehicle.
10. Clear the DTC.
Parts Information
Warranty Information
For vehicles repaired under warranty, use
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins >
Page 6157
Evaporative Emission (EVAP) Canister Vent Solenoid
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emission Control Canister > Canister Vent Valve > Component Information > Technical Service Bulletins >
Page 6158
Canister Vent Valve: Service and Repair
REMOVAL PROCEDURE
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 2. Disconnect the vent pipe (2) from
the evaporative emission (EVAP) canister vent valve. 3. Disconnect the EVAP canister vent valve
electrical connector (3). 4. Detach the EVAP canister vent valve from the EVAP canister vent valve
bracket (1).
INSTALLATION PROCEDURE
1. Install the EVAP canister vent valve to the EVAP canister vent valve bracket (1). 2. Connect the
EVAP canister vent valve electrical connector (3). 3. Connect the vent pipe (2) to the EVAP
canister vent valve. 4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair
Evaporative Emissions Hose: Service and Repair
ENGINE COMPARTMENT EVAP PIPE REMOVAL PROCEDURE
IMPORTANT: When replacing the evaporative emission (EVAP) pipe, always replace the pipe with
original equipment or pans that meet the GM specifications for this part. The replacement pipe
must have the same type of fittings as the original pipe in order to ensure the integrity of the
connection.
1. Clean the pipe connections and the surrounding areas before disconnecting in order to avoid
possible contamination of the EVAP system. 2. Disconnect the engine compartment EVAP pipe (2)
at the EVAP canister purge solenoid (1). 3. Disconnect the engine compartment EVAP pipe (3) at
the chassis EVAP pipe. 4. Remove the EVAP pipe from the engine. 5. Cap the EVAP canister
purge solenoid and the chassis EVAP pipe in order to prevent possible EVAP system
contamination.
ENGINE COMPARTMENT EVAP PIPE INSTALLATION PROCEDURE
1. Remove the caps from the EVAP canister purge solenoid and the chassis EVAP pipe. 2. Install
the EVAP pipe on the engine. 3. Connect the engine compartment EVAP pipe (3) to the chassis
EVAP pipe. 4. Connect the engine compartment EVAP pipe (2) to the EVAP canister purge
solenoid (1).
CHASSIS EVAP PIPE REMOVAL PROCEDURE
IMPORTANT: When replacing the EVAP pipe, always replace the pipe with original equipment or
parts that meet the GM specifications for this part. The replacement pipe must have the same type
of fittings as the original pipe in order to ensure the integrity of the connection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6162
1. Clean all the EVAP pipe connections and the surrounding areas before disconnecting the pipes
in order to avoid possible contamination of the
EVAP system.
2. Disconnect the engine compartment EVAP pipe (6) from the chassis EVAP pipe (3). 3. Cap the
engine compartment EVAP pipe. 4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 5.
Remove the EVAP pipe from the bellhousing stud clip (4). 6. Remove the EVAP pipe from the
transmission bracket clip.
7. Remove the EVAP pipe from the transfer case bracket clip, 4-wheel drive only.
8. Disconnect the rear EVAP purge pipe from the EVAP canister. 9. Cap the rear EVAP purge pipe
(3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6163
10. Note the position of the EVAP pipe for aid in installation. 11. Remove the EVAP pipe from the
retaining clips (1). 12. Remove the EVAP pipe.
CHASSIS EVAP PIPE INSTALLATION PROCEDURE
1. Install the EVAP pipe into the retaining clips (1).
2. Remove the cap from the rear EVAP pipe. 3. Connect the rear EVAP purge pipe to the EVAP
canister.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6164
4. Install the EVAP pipe into the transfer case bracket clip, 4-wheel drive only.
5. Install the EVAP pipe into the transmission bracket clip. 6. Install the EVAP pipe into the
bellhousing stud clip (4). 7. Lower the vehicle. 8. Remove the cap from the engine compartment
EVAP pipe. 9. Connect the engine compartment EVAP pipe (6) to the chassis EVAP pipe (3).
EVAP VENT PIPE REMOVAL PROCEDURE
IMPORTANT: When replacing the EVAP pipe, always replace the pipe with original equipment or
parts that meet the GM specifications for this part. The replacement pipe must have the same type
of fittings as the original pipe in order to ensure the integrity of the connection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6165
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 2. Clean all the EVAP pipe
connections and the surrounding areas before disconnecting in order to avoid possible
contamination of the EVAP
system.
3. Disconnect the EVAP vent pipe at the EVAP canister. 4. Disconnect the EVAP vent pipe at the
EVAP vent valve. 5. Remove the EVAP vent pipe from the mounting clips (1,3,4, and 5). 6. Cap the
EVAP vent valve and the EVAP canister in order to prevent possible EVAP system contamination.
EVAP VENT PIPE INSTALLATION PROCEDURE
1. Remove the caps from the EVAP vent valve and the EVAP canister. 2. Connect the EVAP vent
pipe (2) to the EVAP vent valve. 3. Connect the EVAP vent pipe to the EVAP canister. 4. Install the
EVAP vent pipe into the mounting clips (1,3,4, and 5). 5. Lower the vehicle.
REAR EVAP FUEL TANK PIPE REMOVAL PROCEDURE
IMPORTANT: When replacing the EVAP pipe, always replace the pipe with original equipment or
parts that meet the GM specifications for this part. The replacement pipe must have the same type
of fittings as the original pipe in order to ensure the integrity of the connection.
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6166
1. Disconnect the negative battery cable. 2. Relieve the fuel system pressure. Refer to Fuel
Pressure Relief Procedure. 3. Drain the fuel tank. Refer to Fuel Tank Draining Procedure (Utility
Single Tank) or Fuel Tank Draining Procedure (Utility Dual Tank Front) or
Fuel Tank Draining Procedure (Utility Dual Tank Rear).
4. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 5. Clean all fuel and EVAP pipe and
hose connections and the surrounding areas before disconnection in order to avoid possible
contamination of the
fuel system.
6. Remove the fuel tank.
7. Remove the rear EVAP pipe (1) from the fuel sender (2), the fuel tank roll over valve (3) and the
fuel tank clips (6). 8. Cap the fuel sender EVAP pipe and the fuel tank roll over valve.
REAR EVAP FUEL TANK PIPE INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative Emissions Hose > Component Information > Service and Repair > Page 6167
1. Remove the caps from the fuel sender EVAP pipe and the fuel tank roll over valve. 2. Connect
the rear EVAP pipe (1) to the fuel sender (2), the fuel tank roll over valve (3), and the fuel tank clips
(6).
3. Install the fuel tank. 4. Lower the vehicle. 5. Refill the fuel tank. 6. Connect the negative battery
cable. 7. Tighten the fuel filler cap. 8. Inspect for leaks.
8.1. Turn ON the ignition for 2 seconds.
8.2. Turn OFF the ignition for 10 seconds.
8.3. Turn ON the ignition.
8.4. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Evaporative Emissions System >
Evaporative System Service Port > Component Information > Description and Operation
Evaporative System Service Port: Description and Operation
EVAP SERVICE PORT
The EVAP service port is located in the EVAP purge pipe between the EVAP purge valve and the
EVAP canister. The service port is identified by a green colored cap.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Tube > Component Information > Service and Repair
EGR Tube: Service and Repair
EXHAUST GAS RECIRCULATION (EGR) PIPE REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Avoid breathing fumes and swallowing EGR exhaust deposits when removing
components for cleaning as bodily injury may result.
1. Remove the engine sight shield. 2. Remove the air intake duct. 3. Remove the exhaust gas
recirculation (EGR) valve. 4. Remove the EGR pipe (2) to intake manifold fasteners. 5. Remove the
EGR pipe to exhaust manifold fasteners. 6. Remove the EGR pipe mounting fasteners from the
right cylinder head. 7. Remove the EGR pipe.
INSTALLATION PROCEDURE
1. Install the EGR pipe.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the EGR pipe mounting fasteners to the right cylinder head.
Tighten Tighten the fasteners to 50 N.m (37 lb ft).
3. Install the EGR pipe (2) to exhaust manifold fasteners.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Tube > Component Information > Service and Repair > Page 6175
Tighten Tighten the fasteners to 25 N.m (18 lb ft).
4. Install the EGR pipe to intake manifold fasteners.
Tighten Tighten the fasteners to 12 N.m (106 lb in).
5. Install the EGR valve. 6. Install the air intake duct. 7. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Valve > Component Information > Specifications
EGR Valve: Specifications
Exhaust Gas Recirculation (EGR) Valve Bolts (First Pass)
................................................................................................................. 10 Nm (89 inch lbs.) EGR
Valve Bolts (Final Pass) ......................................................................................................................
............................................ 30 Nm (22 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Valve > Component Information > Specifications > Page 6179
Exhaust Gas Recirculation (EGR) Valve
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Valve > Component Information > Specifications > Page 6180
EGR Valve: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Do not try to disassemble the exhaust gas recirculation (EGR) valve. Service the valve only as a
complete assembly.
- Carefully note the position of the EGR valve before removal. Do not rotate the EGR valve 180
degrees.
1. Remove intake duct. 2. Disconnect the EGR electrical connector. 3. Remove the valve to flange
attaching fasteners.
NOTE: The EGR valve is an electrical component. Soaking the EGR valve in a liquid cleaner or a
solvent causes damage to the valve.
4. Remove the EGR valve. 5. Remove the flange gasket. 6. Clean the EGR valve gasket surface.
INSTALLATION PROCEDURE
1. Install the new flange gasket 2. Install the EGR valve.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the valve to flange fasteners.
Tighten 3.1.
Tighten the fasteners the first time to 10 N.m (89 lb in) each.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Exhaust Gas Recirculation > EGR
Valve > Component Information > Specifications > Page 6181
3.2. Tighten the fasteners a final time to 25 N.m (18 lb ft) each.
4. Connect the electrical connector. 5. Install intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
PCV Valve Hose > Component Information > Service and Repair
PCV Valve Hose: Service and Repair
Crankcase Ventilation Hoses/Pipes Replacement
Removal Procedure
1. Remove the engine sight shield. 2. Remove the positive crankcase ventilation (PCV) tube (1)
from the intake manifold and valve rocker arm cover. 3. Remove the PCV valve (2) from the PCV
tube (1).
4. Remove the vent hose from the throttle body and the valve rocker arm cover. 5. Replace the
hose/tube as necessary.
Installation Procedure
1. Install the hose/tube as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
PCV Valve Hose > Component Information > Service and Repair > Page 6186
2. Install the vent hose to the throttle body and the valve rocker arm cover.
3. Install the PCV valve (2) to the tube (1). 4. Install the PCV tube (1) to the intake manifold and
valve rocker arm cover. 5. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
Positive Crankcase Ventilation Valve > Component Information > Technical Service Bulletins > Customer Interest for
Positive Crankcase Ventilation Valve: > 01-06-01-029B > Jul > 02 > Engine - Greater Than Normal Oil Consumption
Positive Crankcase Ventilation Valve: Customer Interest Engine - Greater Than Normal Oil
Consumption
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 01-06-01-029B
Date: July, 2002
TECHNICAL
Subject: Higher than Expected Engine Oil Consumption (Replace PCV Valve)
Models: 2002 Chevrolet Avalanche 1999-2002 Chevrolet Silverado, Suburban, Tahoe Models 2002
Cadillac Escalade, Escalade EXT 1999-2002 GMC Denali, Sierra, Suburban, Yukon Models with
4.8L, 5.3L or 6.0L Engine (VINS V, T, N, U - RPOs LR4, LM7, LQ9, L04)
This bulletin is being revised to clarify the parts information. Please discard Corporate Bulletin
Number 01-06-01-029A (Section 06 - Engine/Propulsion System).
Condition
Some customers may comment on higher than expected engine oil consumption. They may further
comment on consumption in the range of 3,200 km (2,000 mi) or less per quart (0.946 liter) of oil
under normal driving conditions.
Cause
The condition may be due to the positive crankcase ventilation (PCV) valve flow rate under certain
engine operating conditions.
Correction
1. Verify that the oil consumption is not the result of an oil leak or other engine concern.
2. The dealer should perform an oil consumption test. The vehicle should have accumulated over
6,450 km (4,000 mi) before establishing the oil consumption rate. Reference Corporate Bulletin
Number 01-06-01-011, Information on Engine Oil Consumption Guideline, for details.
3. Remove the PCV valve and inspect the hose going to the intake manifold for signs of excessive
oil being present.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
Positive Crankcase Ventilation Valve > Component Information > Technical Service Bulletins > Customer Interest for
Positive Crankcase Ventilation Valve: > 01-06-01-029B > Jul > 02 > Engine - Greater Than Normal Oil Consumption > Page
6195
4. If excessive oil is present in the PCV hose, replace the PCV valve (Type 948C) (2) with a
new-style fixed orifice PCV valve, GM P/N 12572717 (1). See the illustration shown.
Important:
The new style fixed orifice PCV valve contains no moving parts, and does not rattle when shaken.
If the vehicle has an orifice style PCV valve, investigate other causes for high oil consumption.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
Positive Crankcase Ventilation Valve > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Positive Crankcase Ventilation Valve: > 01-06-01-029B > Jul > 02 > Engine - Greater Than Normal Oil
Consumption
Positive Crankcase Ventilation Valve: All Technical Service Bulletins Engine - Greater Than Normal
Oil Consumption
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 01-06-01-029B
Date: July, 2002
TECHNICAL
Subject: Higher than Expected Engine Oil Consumption (Replace PCV Valve)
Models: 2002 Chevrolet Avalanche 1999-2002 Chevrolet Silverado, Suburban, Tahoe Models 2002
Cadillac Escalade, Escalade EXT 1999-2002 GMC Denali, Sierra, Suburban, Yukon Models with
4.8L, 5.3L or 6.0L Engine (VINS V, T, N, U - RPOs LR4, LM7, LQ9, L04)
This bulletin is being revised to clarify the parts information. Please discard Corporate Bulletin
Number 01-06-01-029A (Section 06 - Engine/Propulsion System).
Condition
Some customers may comment on higher than expected engine oil consumption. They may further
comment on consumption in the range of 3,200 km (2,000 mi) or less per quart (0.946 liter) of oil
under normal driving conditions.
Cause
The condition may be due to the positive crankcase ventilation (PCV) valve flow rate under certain
engine operating conditions.
Correction
1. Verify that the oil consumption is not the result of an oil leak or other engine concern.
2. The dealer should perform an oil consumption test. The vehicle should have accumulated over
6,450 km (4,000 mi) before establishing the oil consumption rate. Reference Corporate Bulletin
Number 01-06-01-011, Information on Engine Oil Consumption Guideline, for details.
3. Remove the PCV valve and inspect the hose going to the intake manifold for signs of excessive
oil being present.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
Positive Crankcase Ventilation Valve > Component Information > Technical Service Bulletins > All Technical Service
Bulletins for Positive Crankcase Ventilation Valve: > 01-06-01-029B > Jul > 02 > Engine - Greater Than Normal Oil
Consumption > Page 6201
4. If excessive oil is present in the PCV hose, replace the PCV valve (Type 948C) (2) with a
new-style fixed orifice PCV valve, GM P/N 12572717 (1). See the illustration shown.
Important:
The new style fixed orifice PCV valve contains no moving parts, and does not rattle when shaken.
If the vehicle has an orifice style PCV valve, investigate other causes for high oil consumption.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Emission Control Systems > Positive Crankcase Ventilation >
Positive Crankcase Ventilation Valve > Component Information > Technical Service Bulletins > Page 6202
Positive Crankcase Ventilation Valve: Service and Repair
Positive Crankcase Ventilation (PCV) Valve Replacement
Removal Procedure
1. Remove the engine sight shield, if required. 2. Remove the positive crankcase ventilation (PCV)
tube (1) from the rocker arm cover. 3. Remove the PCV valve (2) from the PCV tube (1).
Installation Procedure
1. Install a new PCV valve (2) to the PCV tube (1). 2. Install the PCV tube (1) to the rocker arm
cover. 3. Install the engine sight shield, if required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > Specifications
Fuel Pressure: Specifications
Measure with the Key On Engine Off with the fuel pump commanded ON.
Vin (V,T,U)
Fuel Pressure (gasoline) .....................................................................................................................
................................................................. 55-62 psi
Vin (Z)
Fuel Pressure (ethanol) .......................................................................................................................
................................................................. 48-54 psi
These specifications are taken from the Fuel System Diagnosis. For complete testing of fuel
pressures and volume see Fuel System Diagnosis, See: Computers and Control Systems/Testing
and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal
Fuel Pressure: Testing and Inspection Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6209
Fuel Pressure: Testing and Inspection Fuel System Diagnosis
SYSTEM DESCRIPTION
When you turn ON the ignition switch, the control module enables the fuel pump relay which
powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running
and the control module receives ignition reference pulses. If there are no ignition reference pulses,
the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the
ON position or if the engine stops.
The fuel tank stores the fuel supply. The electric fuel pump supplies fuel through an in-line fuel filter
to the fuel injection system. The pump provides fuel at a higher rate of flow than is needed by the
fuel injection system. The fuel pressure regulator maintains the correct fuel pressure to the fuel
injection system. A separate pipe returns unused fuel to the fuel tank.
TEST DESCRIPTION
Steps 1-2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6210
Steps 3-7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6211
Steps 8-13
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6212
Steps 14-18
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure > System
Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6213
Steps 19-25
The numbers below refer to the step numbers on the diagnostic table. 2. This step verifies that the
fuel pump is operating. 4. This step tests for an internal fuel leak. If the fuel pressure drops during
this test, then an internal loss of pressure is indicated. 6. This step tests the fuel pressure regulator.
The fuel pressure regulator is controlled by the engine vacuum. With the engine vacuum applied,
the
pressure should drop to the specified value.
9. This step inspects the fuel pressure regulator for a fuel leak from the vacuum port. If fuel leaks
from the fuel pressure regulator while the fuel
pump is commanded ON, replace the fuel pressure regulator.
10. This step tests for a loss of fuel pressure between the fuel feed pipe shut-off adapter and the
fuel pump. 11. This step tests for a leaking fuel injector or for a leaking fuel pressure regulator. If
the fuel pressure remains constant during this test, the fuel
injectors are not leaking fuel.
14. This step tests for a restricted fuel return pipe. If the fuel pressure is within the specified values,
there is a restriction in the fuel return pipe. 16. This step determines if the fuel pressure regulator or
the fuel pump is the cause of the low fuel pressure. If the pressure rises above the specified
value, the fuel pump is OK.
18. This step verifies that a circuit condition is not the cause of a fuel pressure concern. Thoroughly
inspect all fuel electrical circuits.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure Release >
System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure Release >
System Information > Service and Repair > Fuel Pressure Gage Installation and Removal > Page 6218
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed > System
Information > Specifications
Idle Speed: Specifications
Idle Speed ...........................................................................................................................................
.............................................................. 500-700 rpm
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal >
Component Information > Service and Repair
Accelerator Pedal: Service and Repair
ACCELERATOR CONTROLS PEDAL REPLACEMENT
REMOVAL PROCEDURE
1. Remove the left instrument panel (IP) insulator. 2. Disconnect the accelerator cable retainer (3)
from the accelerator pedal lever (2). 3. Remove the end bushing retaining clips. 4. Remove the end
bushings from the pivot shaft. 5. Remove the accelerator pedal.
INSTALLATION PROCEDURE
1. Install the accelerator pedal. 2. Install the end bushings to the pivot shaft. 3. Install the end
bushing retaining clips. 4. Install the accelerator cable through the slot in the accelerator pedal
lever (2). 5. Seat the retainer (3) in the accelerator pedal lever (2). 6. Test for complete throttle
opening and closing range by operating the accelerator pedal. Also inspect the carpet fit under the
accelerator pedal. The
throttle should operate freely and without binding between full closed throttle and wide open throttle
(WOT).
7. Install the left IP insulator.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal Position
Sensor > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 6228
Accelerator Pedal Position (APP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 6229
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 6230
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Accelerator Pedal Position
Sensor > Component Information > Locations > Page 6231
1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air
Cleaner Restriction Indicator > Component Information > Description and Operation
Air Cleaner Restriction Indicator: Description and Operation
Air Cleaner Restriction Indicator
The air cleaner restriction indicator is located on the air cleaner assembly between the air filter and
the mass air flow (MAF) sensor.
If the area inside of the clear section is green, no air filter service is required. If the area inside the
clear section is orange and Change Air Filter appears, replace the air filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: Customer Interest Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Customer Interest for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 6244
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON
Air Filter Element: All Technical Service Bulletins Engine, A/T - Shift/Driveability Concerns/MIL ON
Bulletin No.: 04-07-30-013B
Date: February 01, 2007
INFORMATION
Subject: Automatic Transmission Shift, Engine Driveability Concerns or Service Engine Soon
(SES) Light On as a Result of the Use of an Excessively/Over-Oiled Aftermarket, Reusable Air
Filter
Models: 2007 and Prior GM Cars and Light Duty Trucks 2007 and Prior Saturn Models 2003-2007
HUMMER H2 2006-2007 HUMMER H3 2005-2007 Saab 9-7X
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 04-07-30-013A (Section 07 - Transmission/Transaxle).
The use of an excessively/over-oiled aftermarket, reusable air filter may result in:
Service Engine Soon (SES) light on
Transmission shift concerns, slipping and damaged clutch(es) or band(s)
Engine driveability concerns, poor acceleration from a stop, limited engine RPM range
The oil that is used on these air filter elements may be transferred onto the Mass Air Flow (MAF)
sensor causing contamination of the sensor. As a result, the Grams per Second (GPS) signal from
the MAF may be low and any or all of the concerns listed above may occur.
When servicing a vehicle with any of these concerns, be sure to check for the presence of an
aftermarket reusable, excessively/over-oiled air filter. The MAF, GPS reading should be compared
to a like vehicle with an OEM air box and filter under the same driving conditions to verify the
concern.
The use of an aftermarket reusable air filter DOES NOT void the vehicle's warranty.
If an aftermarket reusable air filter is used, technicians should inspect the MAF sensor element and
the air induction hose for contamination of oil prior to making warranty repairs.
Transmission or engine driveability concerns (related to the MAF sensor being contaminated with
oil) that are the result of the use of an aftermarket reusable, excessively/over-oiled air filter are not
considered to be warrantable repair items.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Air Filter Element: >
04-07-30-013B > Feb > 07 > Engine, A/T - Shift/Driveability Concerns/MIL ON > Page 6250
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Page 6251
Air Filter Element: Service and Repair
AIR CLEANER ELEMENT REPLACEMENT
REMOVAL PROCEDURE
1. Remove the intake duct (2). 2. Disconnect the electrical connector from the mass air flow/intake
air temperature (MAF/IAT) sensor.
3. Loosen the 4 fasteners (8) securing the air cleaner housing top cover (4). 4. Lift and rotate the
top cover (4) of the air cleaner housing to gain access to the air filter element. 5. Lift out the air filter
element (5). 6. Inspect the air filter element for dust, dirt, or water. Clean or replace the air filter
element if required.
INSTALLATION PROCEDURE
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Cleaner Housing > Air Filter
Element > Component Information > Technical Service Bulletins > Page 6252
1. Install the air filter element (5) into the air cleaner housing. 2. Rotate and install the top cover (4)
to the air cleaner housing (6). 3. Insert the fasteners (8) to secure the top cover.
4. Connect the MAF/IAT electrical connector. 5. Install the intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6258
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6259
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6260
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6261
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6262
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6263
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6264
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6265
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6266
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6267
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6283
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6284
Equivalents - Decimal And Metric Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6285
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6286
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6287
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6288
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Page 6289
Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Air Flow Meter/Sensor >
Component Information > Diagrams > Page 6290
2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Flexible Fuel Sensor >
Component Information > Diagrams
Fuel Composition Sensor - W/L59 Only
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Flexible Fuel Sensor >
Component Information > Diagrams > Page 6294
Flexible Fuel Sensor: Description and Operation
FUEL COMPOSITION SENSOR DESCRIPTION
The Fuel Composition Sensor (FCS), or flex fuel sensor (service parts term), measures the
ethanol-gasoline ratio of the fuel being used in a flexible fuel vehicle. Flexible fuel vehicles can be
operated with a blend of ethanol and gasoline, up to 85 percent ethanol. In order to adjust the
ignition timing and the fuel quantity to be injected, the engine management system requires
information about the percentage of ethanol in the fuel.
The FCS uses quick-connect style fuel connections, an incoming fuel connection, and an outgoing
fuel connection. The two connections have different diameters, to prevent incorrect attachment of
the fuel lines. All fuel passes through the fuel composition sensor before continuing on to the fuel
rail. The fuel composition sensor measures two different fuel related parameters, and sends an
electrical signal to the Powertrain Control Module (PCM) to indicate ethanol percentage, and fuel
temperature.
The fuel composition sensor has a three-wire electrical harness connector. The three wires provide
a ground circuit, a power source, and a signal output to the PCM. The power source is vehicle
system voltage, +12 volts), and the ground circuit connects to chassis ground. The signal circuit
carries both the ethanol percentage and fuel temperature within the same signal, on the same wire.
The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel
temp, and change an output signal accordingly. The electrical characteristic of the FCS signal is a
square-wave digital signal. The signal is both variable frequency and variable pulse width. The
frequency of the signal indicates the ethanol percentage, and the pulse width indicates the fuel
temperature. The PCM provides an internal pull-up to five volts on the signal circuit, and the FCS
pulls the 5 volts to ground in pulses. The output frequency is linear to the percentage of ethanol
content in the fuel. The normal range of operating frequency is between 50 and 150 Hertz, with 50
Hertz representing 0 percent ethanol, and 150 Hertz representing 100 percent ethanol. The normal
pulse width range of the digital pulses is between 1 and 5 milliseconds, with 1 millisecond
representing 40°C (-40°F), and 5 milliseconds representing 125°C (257°F).
The microprocessor inside the sensor is capable of a certain amount of self-diagnosis. An output
frequency of 170 Hertz indicates either that the fuel is contaminated or contains methanol (it should
not), or that an internal sensor electrical fault has been detected. Certain substances dissolved in
the fuel can cause the fuel to be contaminated, raising the output frequency to be higher than the
actual ethanol percentage should indicate. Examples of these substances include water, sodium
chloride (salt), and methanol.
It should be noted that it is likely that the FCS will indicate a slightly lower ethanol percentage than
what is advertised at the fueling station. This is not a fault of the sensor. The reason has to do with
government requirements for alcohol-based motor fuels. Government regulations require that
alcohol intended for use as motor fuel be DENATURED. This means that 100 percent pure ethanol
is first denatured with approximately 4% percent gasoline, before being mixed with anything else.
When an ethanol gasoline mixture is advertised as E85, the 85 percent ethanol was denatured
before being blended with gasoline, meaning an advertised E85 fuel contains only about 81
percent ethanol. The FCS measures the actual percentage of ethanol in the fuel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Flexible Fuel Sensor >
Component Information > Diagrams > Page 6295
Flexible Fuel Sensor: Service and Repair
FUEL COMPOSITION SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Turn OFF the ignition. 2. Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure. 3.
Raise the vehicle. 4. Remove the fuel composition sensor fuel composition sensor (FCS)
attachment nuts (1).
5. Disconnect the FCS inlet and outlet pipes from the FCS.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Flexible Fuel Sensor >
Component Information > Diagrams > Page 6296
6. Disconnect the FCS electrical connector (1). 7. Remove the FCS and bracket assembly from the
frame rail.
8. Remove the FCS bolts and remove from the bracket.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Page 6297
1. Install the FCS to the bracket and install bolts.
Tighten Tighten bolts to 10 N.m (89 lb in).
2. Install FCS and bracket assembly to frame.
3. Install FCS bracket to frame nuts.
Tighten Tighten nuts (1) to 17 N.m (13 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Flexible Fuel Sensor >
Component Information > Diagrams > Page 6298
4. Connect the FCS inlet and outlet pipes to the FCS.
5. Connect the FCS electrical connector (1). 6. Lower the vehicle. 7. Start the engine and check for
fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada)
Fuel: Technical Service Bulletins Fuel System - TOP TIER Detergent Gasoline (Canada)
INFORMATION
Bulletin No.: 05-06-04-022G
Date: October 27, 2010
Subject: TOP TIER Detergent Gasoline Information and Available Brands (Deposits, Fuel
Economy, No Start, Power, Performance, Stall Concerns) - Canada ONLY
Models:
2011 and Prior GM Passenger Cars and Trucks (Canada Only)
Supercede: This bulletin is being revised to update the model years and include an additional
gasoline brand as a TOP TIER source. Please discard Corporate Bulletin Number 05-06-04-022F
(Section 06 - Engine/Propulsion System). In the U.S., refer to the latest version of Corporate
Bulletin Number 04-06-04-047I.
A new class of fuel called TOP TIER Detergent Gasoline is appearing at retail stations of some fuel
marketers. This gasoline meets detergency standards developed by six automotive companies. All
vehicles will benefit from using TOP TIER Detergent Gasoline over gasoline containing the "Lowest
Additive Concentration" recommended by the Canadian General Standards Board (CGSB). Those
vehicles that have experienced deposit related concerns may especially benefit from use of TOP
TIER Detergent Gasoline.
Intake valve: 16,093 km (10,000 mi) with TOP TIER Detergent Gasoline
Intake valve: 16,093 km (10,000 mi) with Minimum Additive recommended by the CGSB
Top Tier Fuel Availability
Chevron was the first to offer TOP TIER Detergent Gasoline in Canada. Shell became the first
national gasoline retailer to offer TOP TIER Detergent Gasoline across Canada. Petro-Canada
began offering TOP TIER Detergent Gasoline nationally as of October 1, 2006. Sunoco began
offering TOP TIER Detergent Gasoline in March of 2007. Esso began offering TOP TIER Detergent
Gasoline in May of 2010.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6303
Gasoline Brands That Currently Meet TOP TIER Detergent Gasoline Standards
The following gasoline brands meet the TOP TIER Detergent Gasoline Standards in all octane
grades :
Chevron Canada (markets in British Columbia and western Alberta)
- Shell Canada (nationally)
- Petro-Canada (nationally)
- Sunoco-Canada (Ontario)
- Esso-Canada (nationally)
What is TOP TIER Detergent Gasoline?
TOP TIER Detergent Gasoline is a new class of gasoline with enhanced detergency and no
metallic additives. It meets new, voluntary deposit control standards developed by six automotive
companies that exceed the detergent recommendations of Canadian standards and does not
contain metallic additives, which can damage vehicle emission control components.
Where Can TOP TIER Detergent Gasoline Be Purchased?
The TOP TIER program began in the U.S. and Canada on May 3, 2004. Some fuel marketers have
already joined and introduced TOP TIER Detergent Gasoline. This is a voluntary program and not
all fuel marketers will offer this product. Once fuel marketers make public announcements, they will
appear on a list of brands that meet the TOP TIER standards.
Who developed TOP TIER Detergent Gasoline standards?
TOP TIER Detergent Gasoline standards were developed by six automotive companies: BMW,
General Motors, Honda, Toyota, Volkswagen and Audi.
Why was TOP TIER Detergent Gasoline developed?
TOP TIER Detergent Gasoline was developed to increase the level of detergent additive in
gasoline. In the U.S., government regulations require that all gasoline sold in the U.S. contain a
detergent additive. However, the requirement is minimal and in many cases, is not sufficient to
keep engines clean. In Canada, gasoline standards recommend adherence to U.S. detergency
requirements but do not require it. In fact, many brands of gasoline in Canada do not contain any
detergent additive. In order to meet TOP TIER Detergent Gasoline standards, a higher level of
detergent is needed than what is required or recommended, and no metallic additives are allowed.
Also, TOP TIER was developed to give fuel marketers the opportunity to differentiate their product.
Why did the six automotive companies join together to develop TOP TIER?
All six corporations recognized the benefits to both the vehicle and the consumer. Also, joining
together emphasized that low detergency and the intentional addition of metallic additives is an
issue of concern to several automotive companies.
What are the benefits of TOP TIER Detergent Gasoline?
TOP TIER Detergent Gasoline will help keep engines cleaner than gasoline containing the "Lowest
Additive Concentration" recommended by Canadian standards. Clean engines help provide optimal
fuel economy and engine performance, and also provide reduced emissions. Also, the use of TOP
TIER Detergent Gasoline will help reduce deposit related concerns.
Who should use TOP TIER Detergent Gasoline?
All vehicles will benefit from using TOP TIER Detergent Gasoline over gasoline containing the
"Lowest Additive Concentration" recommended by Canadian standards. Those vehicles that have
experienced deposit related concerns may especially benefit from use of TOP TIER Detergent
Gasoline. More information on TOP TIER Detergent Gasoline can be found at this website,
http://www.toptiergas.com/.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6304
Disclaimer
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6305
Fuel: Technical Service Bulletins Fuel System - 'TOP TIER' Detergent Gasoline Information
INFORMATION
Bulletin No.: 04-06-04-047I
Date: August 17, 2009
Subject: TOP TIER Detergent Gasoline (Deposits, Fuel Economy, No Start, Power, Performance,
Stall Concerns) - U.S. Only
Models:
2010 and Prior GM Passenger Cars and Trucks (including Saturn) (U.S. Only) 2003-2010
HUMMER H2 (U.S. Only) 2006-2010 HUMMER H3 (U.S. Only) 2005-2009 Saab 9-7X (U.S. Only)
Supercede: This bulletin is being revised to add model years and additional sources to the Top Tier
Fuel Retailers list. Please discard Corporate Bulletin Number 04-06-04-047H (Section 06 Engine/Propulsion System). In Canada, refer to Corporate Bulletin Number 05-06-04-022F.
A new class of fuel called TOP TIER Detergent Gasoline is appearing at retail stations of some fuel
marketers. This gasoline meets detergency standards developed by six automotive companies. All
vehicles will benefit from using TOP TIER Detergent Gasoline over gasoline containing the "Lowest
Additive Concentration" set by the EPA. Those vehicles that have experienced deposit related
concerns may especially benefit from the use of TOP TIER Detergent Gasoline.
Intake valve: - 10,000 miles with TOP TIER Detergent Gasoline
Intake valve: - 10,000 miles with Legal Minimum additive
Gasoline Brands That Currently Meet TOP TIER Detergent Gasoline Standards
As of August 1, 2009, all grades of the following gasoline brands meet the TOP TIER Detergent
Gasoline Standards:
- Chevron
- Chevron-Canada
- QuikTrip
- Conoco
Phillips 66
- 76
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6306
- Shell
- Shell-Canada
- Entec Stations located in the greater Montgomery, Alabama area.
- MFA Oil Company located throughout Missouri.
- Kwik Trip, Inc. in Minnesota and Wisconsin and Kwik Star convenience stores in Iowa.
The Somerset Refinery, Inc. at Somerset Oil stations in Kentucky.
Aloha Petroleum
- Tri-Par Oil Company
- Turkey Hill Minit Markets
- Texaco
- Petro-Canada
- Sunoco-Canada
- Road Ranger located in Illinois, Indiana, Iowa, Kentucky, Missouri, Ohio and Wisconsin
What is TOP TIER Detergent Gasoline?
TOP TIER Detergent Gasoline is a new class of gasoline with enhanced detergency. It meets new,
voluntary deposit control standards developed by six automotive companies that exceed the
detergent requirements imposed by the EPA.
Where Can TOP TIER Detergent Gasoline Be Purchased?
The TOP TIER program began on May 3, 2004 and many fuel marketers have joined the program
and have introduced TOP TIER Detergent Gasoline. This is a voluntary program and not all fuel
marketers will offer this product. Once fuel marketers make public announcements, they will appear
on a list of brands that meet the TOP TIER standards.
Where Can I find the Latest Information on TOP TIER Fuel and Retailers?
On the web, please visit www.toptiergas.com for additional information and updated retailer lists.
Who developed TOP TIER Detergent Gasoline standards?
TOP TIER Detergent Gasoline standards were developed by six automotive companies: Audi,
BMW, General Motors, Honda, Toyota and Volkswagen.
Why was TOP TIER Detergent Gasoline developed?
TOP TIER Detergent Gasoline was developed to increase the level of detergent additive in
gasoline. The EPA requires that all gasoline sold in the U.S. contain a detergent additive. However,
the requirement is minimal and in many cases, is not sufficient to keep engines clean. In order to
meet TOP TIER Detergent Gasoline standards, a higher level of detergent is needed than what is
required by the EPA. Also, TOP TIER was developed to give fuel marketers the opportunity to
differentiate their product.
Why did the six automotive companies join together to develop TOP TIER?
All six corporations recognized the benefits to both the vehicle and the consumer. Also, joining
together emphasized that low detergency is an issue of concern to several automotive companies.
What are the benefits of TOP TIER Detergent Gasoline?
TOP TIER Detergent Gasoline will help keep engines cleaner than gasoline containing the "Lowest
Additive Concentration" set by the EPA. Clean engines help provide optimal fuel economy and
performance and reduced emissions. Also, use of TOP TIER Detergent Gasoline will help reduce
deposit related concerns.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6307
Fuel: Technical Service Bulletins Fuel System - E85 Fuel Usage Precautions
Bulletin No.: 05-06-04-035C
Date: July 30, 2007
INFORMATION
Subject: Usage of E85 Fuels in GM Vehicles
Models: 1997-2008 GM Passenger Cars and Trucks (including Saturn) 2003-2008 HUMMER H2
2006-2008 HUMMER H3 1997-2008 Isuzu NPR Commercial Medium Duty Trucks 2005-2008
Saab 9-7X
Supercede:
This bulletin is being revised to add the 2008 model year and additional engines with E85
capability. Please discard Corporate Bulletin Number 05-06-04-035B (Section 06 Engine/Propulsion System).
Customer Interest in E85 Fuel
As the retail price of gasoline increases, some locations in the country are seeing price differentials
between regular gasoline and E85 where E85 is selling for substantially less than regular grade
gasoline. One result of this is that some customers have inquired if they are able to use E85 fuel in
non-E85 compatible vehicles.
Only vehicles designated for use with E85 should use E85 blended fuel.
E85 compatibility is designated for vehicles that are certified to run on up to 85% ethanol and 15%
gasoline. All other gasoline engines are designed to run on fuel that contains no more than 10%
ethanol.
Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause
driveability issues, service engine soon indicators as well as increased fuel system corrosion.
Using E85 Fuels in Non-Compatible Vehicles
General Motors is aware of an increased number of cases where customers have fueled
non-FlexFuel designated vehicles with E85. Fueling non-FlexFuel designated vehicles with E85, or
with fuels where the concentration of ethanol exceeds the ASTM specification of 10%, will result in
one or more of the following conditions:
Lean Driveability concerns such as hesitations, sags and/or possible stalling.
SES lights due to OBD codes.
Fuel Trim codes P0171 and/or P0174.
Misfire codes (P0300).
Various 02 sensor codes.
Disabled traction control or Stability System disabled messages.
Harsh/Firm transmission shifts.
Fuel system and/or engine mechanical component degradation.
Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause
driveability issues, service engine soon indicators as well as increased fuel system corrosion.
If the dealer suspects that a non-FlexFuel designated vehicle brought in for service has been
fueled with E85, the fuel in the vehicle's tank should be checked for alcohol content with tool J
44175. If the alcohol content exceeds 10% the fuel should be drained and the vehicle refilled with
gasoline - preferably one of the Top Tier brands.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6308
Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms
of the New Vehicle Warranty.
A complete list of GM's FlexFuel vehicles can be found in this Service Bulletin, or at
www.livegreengoyellow.com.
E85 Compatible Vehicles
The only E85 compatible vehicles produced by General Motors are shown.
Only vehicles that are listed in the E85 Compatible Vehicles section of this bulletin and/or
www.livegreengoyellow.com are E85 compatible.
All other gasoline and diesel engines are NOT E85 compatible.
Use of fuel containing greater than 10% ethanol in non-E85 designated vehicles can cause
driveability issues, service engine soon indicators as well as increased fuel system corrosion.
Repairs to non-FlexFuel vehicles that have been fueled with E85 are not covered under the terms
of the New Vehicle Warranty.
Disclaimer
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> Technical Service Bulletins > Fuel System - TOP TIER Detergent Gasoline (Canada) > Page 6309
Fuel: Technical Service Bulletins Fuel - Top Tier Detergent Gasoline Information
Bulletin No.: 04-06-00-047
Date: June 24, 2004
ADVANCED SERVICE INFORMATION
Subject: Top Tier Detergent Gasoline (Deposits, Fuel Economy, No Start, Power, Performance,
Stall Concerns)
Models: 2005 and Prior All General Motors Passenger Cars and Trucks (U.S. Only)
A new class of gasoline, called Top Tier Detergent Gasoline, will be appearing at retail stations of
some fuel marketers. This gasoline meets detergency standards developed by four automotive
companies. A description of the concept and benefits of Top Tier is provided in the following
question and answer section.
What is Top Tier Detergent Gasoline?
Top Tier Detergent Gasoline is a new class of gasoline with enhanced detergency. It meets new,
voluntary deposit control standards developed by four automotive companies that exceed the
detergent requirements imposed by the EPA.
Who developed Top Tier Detergent Gasoline standards?
Top Tier Detergent Gasoline standards were developed by four automotive companies: BMW,
General Motors, Honda and Toyota.
Why was Top Tier Detergent Gasoline developed?
Top Tier Detergent Gasoline was developed to increase the level of detergent additive in gasoline.
The EPA requires that all gasoline sold in the U.S. contain a detergent additive. However, the
requirement is minimal and in many cases, is not sufficient to keep engines clean. In order to meet
Top Tier Detergent Gasoline standards, a higher level of detergent is needed than what is required
by the EPA. Also, Top Tier was developed to give fuel marketers the opportunity to differentiate
their product.
Why did the four automotive companies join together to develop Top Tier?
All four corporations recognized the benefits to both the vehicle and the consumer. Also, joining
together emphasized that low detergency is an issue of concern to several automotive companies.
What are the benefits of Top Tier Detergent Gasoline?
Top Tier Detergent Gasoline will help keep engines cleaner than gasoline containing the "Lowest
Additive Concentration" set by the EPA. Clean engines help provide optimal fuel economy and
performance and reduced emissions. Also, use of Top Tier Detergent Gasoline will help reduce
deposit related concerns.
Who should use Top Tier Detergent Gasoline?
All vehicles will benefit from using Top Tier Detergent Gasoline over gasoline containing the
"Lowest Additive Concentration" set by the EPA. Those vehicles that have experienced deposit
related concerns may especially benefit from use of Top Tier Detergent Gasoline.
Where can Top Tier Detergent Gasoline be purchased?
The Top Tier program began on May 3, 2004. Some fuel marketers have already joined and are
making plans to introduce Top Tier Detergent Gasoline. This is a voluntary program and not all fuel
marketers will offer this product. Once fuel marketers make public announcements, a list of all fuel
marketers meeting Top Tier standards will be made available. For now, look for the "Top Tier"
designation at the gas pump.
Disclaimer
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Technical Service Bulletins > Page 6310
Fuel: Description and Operation
FUEL SYSTEM SPECIFICATIONS
Use regular unleaded gasoline rated at 87 octane or higher. The manufacturer recommends that
the gasoline meet the specifications which have been developed by the American Automobile
Manufacturers Association (AAMA) and endorsed by the Canadian Motor Vehicle Manufacturers
Association for better vehicle performance and engine protection. Gasoline meeting the AAMA
specification may provide improved driveability and emission control system performance
compared to other gasoline. For more information, write to: American Automobile Manufacturer's
Association, 7430 Second Ave., Suite 300, Detroit, MI, 48202.
Verify that the posted octane is at least 87. If the octane is less than 87, you may get a heavy
knocking noise when you drive. If the engine knock is bad enough, your engine may be damaged.
If you are using fuel rated at 87 octane or higher and you hear heavy knocking, your engine needs
service. Do not worry if you hear a little pinging noise when you are accelerating or driving up a hill.
This is normal and you do not have to buy a higher octane fuel to get rid of pinging. Only the heavy,
constant knock means that you have a problem.
NOTE: Your vehicle was not designed for fuel that contains methanol. Do not use methanol fuel
which car corrode metal parts in your fuel system and also damage plastic and rubber parts. This
kind of damage would not be covered under your warranty.
If your vehicle is certified to meet California emission standards, indicated on the underhood
emission control label, your vehicle is designed to operate on fuels that meet California
specifications. If such fuels are not available in states adopting California emission standards, your
vehicle operates satisfactorily on fuels meeting federal specifications, but emission control system
performance may be affected. The Malfunction Indicator Lamp (MIL) on your instrument panel may
turn ON, and your vehicle may fail a smog-check test. If this occurs, return to your authorized
dealer for diagnosis in order to determine the cause of failure. In the event that the cause of the
condition is determined to be the type of fuels used, repairs may not be covered by your warranty.
Some gasolines that are not reformulated for low emissions may contain an octane-enhancing
additive called Methylcyclopentadienyl Manganese Tricarbonyl (MMT). Ask your service station
operator whether or not the fuel contains MMT.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Testing and Inspection > Alcohol/Contaminants-In-Fuel Diagnosis (W/ Special Tool)
Fuel: Testing and Inspection Alcohol/Contaminants-In-Fuel Diagnosis (W/ Special Tool)
TEST DESCRIPTION
Fuel quality can effect vehicle performance. Gasoline and gasoline blends that are contaminated or
contain excessive amounts of alcohol can effect vehicle driveability, fuel economy, fuel system
components and emissions. Excessive alcohol in the fuel may cause fuel system corrosion,
deterioration of rubber components, and subsequent fuel filter restriction. Some types of alcohol
are more detrimental to fuel system components than others. Ethanol is commonly used in
gasoline, but in concentrations of no more than 10 percent. Some fuels, such as E85, contain a
very high percent of ethanol. Fuel with more than 15 percent ethanol may cause driveability
conditions in vehicles such as hesitation, lack of power, stalling, or no start. If excessive alcohol in
the fuel is suspected, then use the following procedure to test the fuel quality.
TEST PROCEDURE
CAUTION: Refer to Fuel Gage Leak Caution in Service Precautions.
1. Turn ON the J 44175 Fuel Composition Tester. 2. Verify the fuel composition tester is
operational by measuring the IAC frequency output with a DMM. Refer to Measuring Frequency in
Diagnostic Aids. A frequency without a fuel sample in the test cell indicates that the tester is
working correctly.
3. Install the fuel pressure gage. Refer to Fuel Pressure Gage Installation and Removal.
IMPORTANT: You will need to bleed the fuel pressure gage a few times in order to obtain an
accurate fuel sample.
4. Close the bleed valve on the fuel pressure gage. 5. Place the bleed hose (1) of the fuel pressure
gage into the 100 ml beaker. 6. Command the fuel pump ON with a scan tool. 7. Slowly open the
bleed valve on the fuel pressure gage, until an adequate fuel sample is obtained. 8. If water
appears in the fuel sample, clean the fuel system and replace the fuel in the vehicle. Refer to Fuel
System Cleaning.
IMPORTANT: Do not allow any substances other than gasoline, ethanol/gasoline blends, air, or
acetone into the test ports of the fuel composition tester. Contaminants in the fuel composition
tester could result in misdiagnosis.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Testing and Inspection > Alcohol/Contaminants-In-Fuel Diagnosis (W/ Special Tool) > Page 6313
9. Pour the fuel sample from the beaker (1) into the J 44175, until the level of the fuel is at the top
of each fuel test port (2).
10. Observe the diagnostic LEDs on the fuel composition tester.
If the red fuel diagnostic LED is illuminated, a fuel contamination condition exists. Refer to Fuel
System Cleaning.
11. Measure the output frequency of the fuel composition tester.
Fuel Composition Test Examples
12. Subtract 50 from the reading on the DMM to obtain the percentage of alcohol in the fuel
sample. Refer to the examples in the table. 13. If the fuel sample contains more than 15 percent
ethanol, replace the fuel in the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Testing and Inspection > Alcohol/Contaminants-In-Fuel Diagnosis (W/ Special Tool) > Page 6314
Fuel: Testing and Inspection Alcohol/Contaminants-In-Fuel Diagnosis (W/O Special Tool)
Water contamination in the fuel system may cause driveability conditions such as hesitation,
stalling, no start, or misfires in one or more cylinders. Water may collect near a single fuel injector
at the lowest point in the fuel rail, and cause a misfire in that cylinder If the fuel system is
contaminated with water, inspect the fuel system components for rust, or deterioration.
Alcohol concentrations of 10 percent or greater in fuel can be detrimental to fuel system
components. Alcohol contamination may cause fuel system corrosion, deterioration of rubber
components, and subsequent fuel filter restriction. Fuel contaminated with alcohol may cause
driveability conditions such as hesitation, lack of power, stalling, or no start. Some types of alcohol
are more detrimental to fuel system components than others.
Alcohol in Fuel Testing Procedure The fuel sample should be drawn from the bottom of the tank so
that any water present in the tank will be detected. The sample should be bright and clear. If
alcohol contamination is suspected then use the following procedure to test the fuel quality. 1.
Using a 100 ml specified cylinder with 1 ml graduation marks, fill the cylinder with fuel to the 90 ml
mark. 2. Add 10 ml of water in order to bring the total fluid volume to 100 ml and install a stopper.
3. Shake the cylinder vigorously for 10-15 seconds. 4. Carefully loosen the stopper in order to
release the pressure. 5. Re-install the stopper and shake the cylinder vigorously again for 10-15
seconds. 6. Put the cylinder on a level surface for approximately 5 minutes in order to allow
adequate liquid separation.
If alcohol is present in the fuel, the volume of the lower layer, which would now contain both alcohol
and water, will be more than 10 ml. For example, if the volume of the lower layer is increased to 15
ml, this indicates at least 5 percent alcohol in the fuel. The actual amount of alcohol may be
somewhat more because this procedure does not extract all of the alcohol from the fuel.
Particulate Contaminants in Fuel Testing Procedure The fuel sample should be drawn from the
bottom of the tank so that any water present in the tank will be detected. The sample should be
bright and clear. If the sample appears cloudy, or contaminated with water, as indicated by a water
layer at the bottom of the sample, use the following procedure to diagnose the fuel. 1. Using an
approved fuel container, draw approximately 0.5 liter of fuel. 2. Place the cylinder on a level surface
for approximately 5 minutes in order to allow settling of the particulate contamination.
Particulate contamination will show up in various shapes and colors. Sand will typically be identified
by a white or light brown crystals. Rubber will appear as black and irregular particles. If particles
are found clean the entire fuel system thoroughly. Refer to Fuel System Cleaning.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Testing and Inspection > Alcohol/Contaminants-In-Fuel Diagnosis (W/ Special Tool) > Page 6315
Steps 1-7
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel > Component Information
> Testing and Inspection > Page 6316
Fuel: Service and Repair
FUEL SYSTEM CLEANING
1. Remove the fuel sender assembly. 2. Inspect the fuel strainer. Replace a contaminated strainer
and inspect the fuel pump. 3. Inspect the fuel pump inlet for dirt and debris. Replace the fuel pump
if you find dirt or debris in the fuel pump inlet.
IMPORTANT: When flushing the fuel tank, handle the fuel and water mixture as a hazardous
material. Handle the fuel and water mixture in accordance with all applicable local, state, and
federal laws and regulations.
4. Flush the fuel tank with hot water. 5. Pour the water out of the fuel sender assembly opening.
Rock the tank to be sure that removal of the water from the tank is complete. 6. Install the fuel
sender assembly Replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Filler Cap > Component
Information > Description and Operation
Fuel Filler Cap: Description and Operation
Fuel Filler Cap
The fuel fill pipe has a tethered fuel filler cap. A torque-limiting device prevents the cap from being
over tightened. To install the cap, turn the cap clockwise until you hear clicks. This indicates that
the cap is correctly torqued and fully seated. A built-in device indicates that the fuel filler cap is fully
seated. A fuel filler cap that is not fully seated may cause a malfunction in the emission system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Filter > Fuel Pressure
Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal
Fuel Pressure Release: Service and Repair Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Filter > Fuel Pressure
Release > System Information > Service and Repair > Fuel Pressure Gage Installation and Removal > Page 6325
Fuel Pressure Release: Service and Repair Fuel System Pressure Relief
TOOLS REQUIRED
J 34730-1A Fuel Pressure Gage
CAUTION: Relieve the fuel system pressure before servicing fuel system components in order to
reduce the risk of fire and personal injury.
After relieving the system pressure, a small amount of fuel may be released when servicing the fuel
lines or connections. In order to reduce the chance Of personal injury, cover the regulator and the
fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out.
Place the towel in an approved container when the disconnection is complete.
1. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental
attempt is made to start the engine. 2. Remove the engine sight shield. 3. Loosen the fuel filler cap
in order to relieve the fuel tank vapor pressure. 4. Connect the J 34730-1A to the fuel pressure
valve. 5. Install the bleed hose of the gauge into an approved container. 6. Open the valve on the
gauge to bleed the system pressure. The fuel connections are now safe for servicing. 7. Drain any
fuel remaining in the gauge into an approved container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Technical Service Bulletins > Fuel System - Fuel Injector Maintenance Cleaning
Fuel Injector: Technical Service Bulletins Fuel System - Fuel Injector Maintenance Cleaning
Bulletin No.: 04-06-04-051B
Date: January 04, 2006
INFORMATION
Subject: Maintenance Cleaning of Fuel Injectors
Models: 2006 and Prior All General Motors Passenger Cars and Trucks 2003-2006 HUMMER H2
2006 HUMMER H3
Supercede:
This bulletin is being revised to add models and model years and update the name and part
number of GM Fuel System Treatment. Please discard Corporate Bulletin Number 04-06-04-051A
(Section 06 - Engine/Propulsion System).
General Motors is aware that some companies are marketing tools, equipment and programs to
support fuel injector cleaning as a preventative maintenance procedure. General Motors does not
endorse, support or acknowledge the need for fuel injector cleaning as a preventative maintenance
procedure. Fuel injector cleaning is approved only when performed as directed by a published GM
driveability or DTC diagnostic service procedure.
Due to variation in fuel quality in different areas of the country, the only preventative maintenance
currently endorsed by GM regarding its gasoline engine fuel systems is the addition of GM Fuel
System Treatment PLUS, P/N 88861011 (for U.S. ACDelco(R), use P/N 88861013) (in Canada,
P/N 88861012), added to a tank of fuel at each oil change. Refer to Corporate Bulletin Number
03-06-04-030A for proper cleaning instructions.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Specifications > Electrical Specifications
Fuel Injector: Electrical Specifications
Injector Ohms ......................................................................................................................................
............................................................... 11-14 ohms
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Specifications > Electrical Specifications > Page 6332
Fuel Injector: Pressure, Vacuum and Temperature Specifications
Pressure Drop (of average psi) ...........................................................................................................
......................................................................... 1.5 psi
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions
Fuel Injector: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6335
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6336
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6337
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6338
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6339
Fuel Injector: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6340
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Information > Diagrams > Diagram Information and Instructions > Page 6341
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Information > Diagrams > Diagram Information and Instructions > Page 6342
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6357
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6358
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6359
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6360
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6361
Equivalents - Decimal And Metric Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6362
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6363
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6364
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6365
Fuel Injector: Connector Views
Fuel Injector 1
Fuel Injector 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6366
Fuel Injector 3
Fuel Injector 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6367
Fuel Injector 6
Fuel Injector 5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Diagrams > Diagram Information and Instructions > Page 6368
Fuel Injector 7
Fuel Injector 8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test
Fuel Injector: Testing and Inspection Fuel Injector Coil Test
CIRCUIT DESCRIPTION
The control module enables the appropriate fuel injector on the intake stroke for each cylinder.
Ignition voltage is supplied directly to the fuel injectors. The control module controls each fuel
injector by grounding the control circuit via a solid state device called a driver. A fuel injector coil
winding resistance that is too high or too low will affect engine driveability. A fuel injector control
circuit DTC may not set, but a misfire may be apparent. The fuel injector coil windings are affected
by temperature. The resistance of the fuel injector coil windings will increase as the temperature of
the fuel injector increases.
DIAGNOSTIC AIDS
^ Monitoring the misfire current counters, or misfire graph, may help isolate the fuel injector that is
causing the condition.
^ Operating the vehicle over a wide temperature range may help isolate the fuel injector that is
causing the condition.
^ Perform the fuel injector coil test within the conditions of the customers concern. A fuel injector
condition may only be apparent at a certain temperature, or under certain conditions.
^ If the fuel injector coil test does not isolate the condition perform the fuel injector balance test.
Refer to Fuel Injector Balance Test with Special Tool or Fuel Injector Balance Test with Tech 2.
TEST DESCRIPTION
Steps 1-7
The numbers below refer to the step numbers on the diagnostic table. 3. This step tests each fuel
injector resistance within a specific temperature range. If any of the fuel injectors display a
resistance outside of the
specified value, replace the fuel injector.
4. This step determines if all of the fuel injectors are within 3 ohms of each other. If the highest
resistance value is within 3 ohms of the lowest
resistance value, then all of the fuel injector coil windings are OK.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6371
5. This step determines which fuel injector is faulty. After subtracting the highest and lowest
resistance values from the average value, replace the
fuel injector that has the greatest resistance difference from the average.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6372
Fuel Injector: Testing and Inspection Fuel Injector Balance Test With special Tool
CIRCUIT
Fuel Injector Balance Test With Special Tool
Fuel Injector Balance Test Example (Typical)
TEST DESCRIPTION
Steps 1-3
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6373
Steps 4-8
The numbers below refer to the step numbers on the diagnostic table. 3. The engine coolant
temperature (ECT) must be below the operating temperature in order to avoid irregular fuel
pressure readings due to hot soak
fuel boiling.
6. If the pressure drop value for each fuel injector is within 10 kPa (1.5 psi) of the average pressure
drop value, the fuel injectors are flowing
properly. Calculate the pressure drop value for each fuel injector by subtracting the second
pressure reading from the first pressure reading. Refer to the illustration.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6374
Fuel Injector: Testing and Inspection Fuel Injector Balance Test with Tech 2
CIRCUIT DESCRIPTION
The scan tool first energizes the fuel pump and then the injectors for a precise amount of time
allowing a measured amount of fuel into the manifold. This causes a drop in system fuel pressure
that can be recorded and used to compare each injector.
TEST DESCRIPTION
Steps 1-4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6375
Steps 5-8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Fuel Injector Coil Test > Page 6376
Steps 1-7
The numbers below refer to the step numbers on the diagnostic table. 3. The engine coolant
temperature (ECT) must be below the operating temperature in order to avoid irregular fuel
pressure readings due to hot soak
fuel boiling.
4. The fuel pressure should be within the specified range. Refer to Fuel System Diagnosis if the
fuel pressure is not within the specified range.
5. The fuel pressure should reach a steady value. Refer to Fuel System Diagnosis if the fuel
pressure does not stabilize.
6. If the pressure drop value for each fuel injector is within 10 kPa (1.5 psi) of the average pressure
drop value, the fuel injectors are flowing
properly. Calculate the pressure drop value for each fuel injector by subtracting the second
pressure reading from the first pressure reading.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Page 6377
Fuel Injector: Service and Repair
REMOVAL PROCEDURE
NOTE: Use care in removing the fuel injectors in order to prevent damage to the fuel injector
electrical connector pins or the fuel injector nozzles. Do not immerse the fuel injector in any type of
cleaner. The fuel injector is an electrical component and may be damaged by this cleaning method.
IMPORTANT: ^
The Denso fuel injectors that are installed on the 5.3L (L59) E85 application will not have O-rings
and retaining clips serviced separately. Therefore the fuel injectors will be replaced whenever an
O-ring or clip needs to be replaced.
^ The engine oil may be contaminated with fuel if the fuel injectors are leaking.
1. Remove the fuel rail. 2. Remove the fuel injector retainer clip (19). 3. Remove the fuel injector
(17).
4. Discard the fuel injector retainer clip (1). 5. Remove and discard the fuel injector O-ring seals (2,
4) from the injector.
INSTALLATION PROCEDURE
IMPORTANT: When ordering new fuel injectors, you must order the correct injector for the
application being serviced.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Injector > Component
Information > Testing and Inspection > Page 6378
1. The fuel injector (1) is stamped with a part number identification (2). A four-digit build date code
(3), which indicates the month (4), day (5), year
(6), and the shift (7) that built the fuel injector.
2. Lubricate the NEW fuel injector O-ring seals (2, 4) with clean engine oil. 3. Install the NEW fuel
injector O-ring seals onto the fuel injector. 4. Install a NEW retainer clip (1) onto the fuel injector.
5. Install the fuel injector (17) into the fuel rail injector socket with the electrical connector facing
outward. The retainer clip (19) locks on to a flange
on the fuel rail injector socket.
6. Install the fuel rail.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Description and Operation
Fuel Line Coupler: Description and Operation
QUICK-CONNECT FITTINGS
Quick-connect fittings provide a simplified means of installing and connecting fuel system
components. The fittings consist of a unique female connector and a compatible male pipe end.
O-rings, located inside the female connector, provide the fuel seal. Integral locking tabs inside the
female connector hold the fittings together.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Service and Repair > Quick Connect Fitting(S) Service (Metal Collar)
Fuel Line Coupler: Service and Repair Quick Connect Fitting(S) Service (Metal Collar)
TOOL REQUIRED
J 37088-A Tool Set, Fuel Line Quick-Connect Separator
REMOVAL PROCEDURE
1. Relieve the fuel system pressure before servicing any fuel system connection. Refer to the Fuel
Pressure Relief Procedure. 2. Remove the retainer from the quick-connect fitting.
CAUTION: Wear safety glasses when using compressed air in order to prevent eye injury.
3. Blow dirt out of the fitting using compressed air.
4. Choose the correct tool from the J 37088-A tool set for the size of the fitting. Insert the tool into
the female connector, then push inward in order to
release the locking tabs.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Service and Repair > Quick Connect Fitting(S) Service (Metal Collar) > Page 6384
5. Pull the connection apart.
NOTE: If necessary, remove rust or burrs from the fuel pipes with an emery cloth. Use a radial
motion with the fuel pipe end in order to prevent damage to the O-ring sealing surface. Use a clean
shop towel in order to wipe off the male tube ends. Inspect all the connections for dirt and burrs.
Clean or replace the components and assemblies as required.
6. Use a clean shop towel in order to wipe off the male pipe end. 7. Inspect both ends of the fitting
for dirt and burrs. Clean or replace the components as required.
INSTALLATION PROCEDURE
CAUTION: Always apply a few drops Of clean engine oil to the male pipe ends before connecting
the fuel pipe fittings in order to reduce the risk of fire and personal injury. This will ensure proper
reconnection and prevent a possible fuel leak. During normal operation, the O-rings located in the
female connector will swell and may prevent proper reconnection if not lubricated.
1. Apply a few drops of clean engine oil to the male pipe end.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Service and Repair > Quick Connect Fitting(S) Service (Metal Collar) > Page 6385
2. Push both sides of the fitting together in order to snap the retaining tabs into place.
3. Once installed, pull on both sides of the fitting in order to make sure the connection is secure. 4.
Install the retainer to the quick-connect fitting.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Service and Repair > Quick Connect Fitting(S) Service (Metal Collar) > Page 6386
Fuel Line Coupler: Service and Repair Quick Connect Fitting(S) Service (Plastic Collar)
REMOVAL PROCEDURE
1. Relieve the fuel system pressure before servicing any fuel system Connection. Refer to Fuel
Pressure Relief Procedure.
CAUTION: Refer to Safety Glasses and Compressed Air Caution in Service Precautions.
2. Using compressed air, blow any dirt out of the quick-connect fitting.
3. Squeeze the plastic retainer release tabs.
4. Pull the connection apart.
INSTALLATION PROCEDURE
CAUTION: Refer to Fuel Pipe Fitting Caution in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Line Coupler >
Component Information > Service and Repair > Quick Connect Fitting(S) Service (Metal Collar) > Page 6387
1. Apply a few drops of clean engine oil to the male fuel pipe end.
2. Push both sides of the quick-connect fitting together in order to cause the retaining tabs to snap
into place.
3. Once installed, pull on both sides of the quick-connect fitting in order to make sure the
connection is secure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure Regulator >
Component Information > Description and Operation
Fuel Pressure Regulator: Description and Operation
Fuel Pressure Regulator Assembly
The fuel pressure regulator is a vacuum-operated diaphragm relief valve with fuel pump pressure
on one side, and with regulator spring pressure and intake manifold vacuum on the other side. The
fuel pressure regulator maintains a constant pressure differential across the injectors at all times.
The pressure regulator compensates for engine load by increasing the fuel pressure when the
engine vacuum drops.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure Regulator >
Component Information > Description and Operation > Page 6391
Fuel Pressure Regulator: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Three styles of fuel pressure regulators and fuel rails will be used in this model year.
Each regulator has a different "footprint" that consequently changes the size of the receiving port in
the fuel rail. The regulator retaining clips are specific to each rail-regulator design and cannot be
interchanged.
1. Remove the engine sight shield. 2. Relieve the fuel system pressure. Refer to Fuel Pressure
Relief Procedure. 3. Disconnect the fuel pressure regulator vacuum line. 4. Clean any dirt from the
fuel pressure regulator retainer and the surrounding area. 5. Remove the fuel pressure regulator
retainer (8). 6. Remove the fuel pressure regulator (9). 7. Ensure none of the following parts are
still in the fuel rail:
^ Backup ring (10)
^ Regulator Seal O-ring (11)
^ Regulator filter (12)
^ Regulator seal O-ring (13)
INSTALLATION PROCEDURE
1. Ensure that the NEW fuel pressure regulator retainer is the correct one. 2. The tabs (1) are used
on the straight vacuum port retainer (2), and the E85-straight vacuum port retainer (3). 3. The angle
vacuum port retainer (4) has no tabs.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pressure Regulator >
Component Information > Description and Operation > Page 6392
4. Install the following parts onto the fuel pressure regulator (9), if necessary.
^ Backup ring (10)
^ Regulator seal O-ring (11)
^ Regulator filter (12)
^ Regulator seal O-ring (13)
5. Lubricate the fuel pressure regulator O-rings (11,13) with clean engine oil. 6. Install the fuel
pressure regulator (9).
IMPORTANT: Whenever the fuel pressure regulator is removed from the fuel rail NEW O-rings and
a NEW retaining clip should be used on reinstallation.
7. Install the NEW fuel pressure regulator retainer (8). 8. Connect the fuel pressure regulator
vacuum line. 9. Tighten the fuel filler cap.
10. Inspect for leaks.
10.1. Turn ON the ignition with the engine OFF, for 2 seconds. 10.2. Turn OFF the ignition for 10
seconds. 10.3. Turn ON the ignition, with the engine OFF. 10.4. Inspect for fuel leaks.
11. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pressure >
System Information > Specifications
Fuel Pressure: Specifications
Measure with the Key On Engine Off with the fuel pump commanded ON.
Vin (V,T,U)
Fuel Pressure (gasoline) .....................................................................................................................
................................................................. 55-62 psi
Vin (Z)
Fuel Pressure (ethanol) .......................................................................................................................
................................................................. 48-54 psi
These specifications are taken from the Fuel System Diagnosis. For complete testing of fuel
pressures and volume see Fuel System Diagnosis, See: Computers and Control Systems/Testing
and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal
Fuel Pressure: Testing and Inspection Fuel Pressure Gage Installation and Removal
FUEL PRESSURE GAGE INSTALLATION AND REMOVAL
INSTALLATION PROCEDURE
CAUTION: ^
Refer to Gasoline/Gasoline Vapors Caution in Service Precautions.
^ Refer to Fuel Gage Leak Caution in Service Precautions.
NOTE: Clean all of the following areas before performing any disconnections in order to avoid
possible contamination in the system:
^ The fuel pipe connections
^ The hose connections
^ The areas surrounding the connections
1. Install the fuel pressure gauge to the fuel pressure service connection, located on the fuel rail. 2.
Turn ON the ignition.
CAUTION: Refer to Fuel Storage Caution in Service Precautions.
3. Place the bleed hose of the fuel pressure gauge into an approved gasoline container. 4. Open
the bleed valve on the fuel pressure gauge in order to bleed the air from the fuel pressure gage. 5.
Command the fuel pump ON with a scan tool. 6. Close the bleed valve on the fuel pressure gauge.
7. Inspect for fuel leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pressure >
System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6399
Fuel Pressure: Testing and Inspection Fuel System Diagnosis
SYSTEM DESCRIPTION
When you turn ON the ignition switch, the control module enables the fuel pump relay which
powers the fuel pump ON. The fuel pump remains ON as long as the engine is cranking or running
and the control module receives ignition reference pulses. If there are no ignition reference pulses,
the control module shuts the fuel pump OFF within 2 seconds after the ignition was switched to the
ON position or if the engine stops.
The fuel tank stores the fuel supply. The electric fuel pump supplies fuel through an in-line fuel filter
to the fuel injection system. The pump provides fuel at a higher rate of flow than is needed by the
fuel injection system. The fuel pressure regulator maintains the correct fuel pressure to the fuel
injection system. A separate pipe returns unused fuel to the fuel tank.
TEST DESCRIPTION
Steps 1-2
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System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6400
Steps 3-7
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System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6401
Steps 8-13
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System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6402
Steps 14-18
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System Information > System Diagnosis > Fuel Pressure Gage Installation and Removal > Page 6403
Steps 19-25
The numbers below refer to the step numbers on the diagnostic table. 2. This step verifies that the
fuel pump is operating. 4. This step tests for an internal fuel leak. If the fuel pressure drops during
this test, then an internal loss of pressure is indicated. 6. This step tests the fuel pressure regulator.
The fuel pressure regulator is controlled by the engine vacuum. With the engine vacuum applied,
the
pressure should drop to the specified value.
9. This step inspects the fuel pressure regulator for a fuel leak from the vacuum port. If fuel leaks
from the fuel pressure regulator while the fuel
pump is commanded ON, replace the fuel pressure regulator.
10. This step tests for a loss of fuel pressure between the fuel feed pipe shut-off adapter and the
fuel pump. 11. This step tests for a leaking fuel injector or for a leaking fuel pressure regulator. If
the fuel pressure remains constant during this test, the fuel
injectors are not leaking fuel.
14. This step tests for a restricted fuel return pipe. If the fuel pressure is within the specified values,
there is a restriction in the fuel return pipe. 16. This step determines if the fuel pressure regulator or
the fuel pump is the cause of the low fuel pressure. If the pressure rises above the specified
value, the fuel pump is OK.
18. This step verifies that a circuit condition is not the cause of a fuel pressure concern. Thoroughly
inspect all fuel electrical circuits.
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> Component Information > Locations > Fuel Pump Relay
Fuel Pump Relay: Locations Fuel Pump Relay
FUEL PUMP RELAY
Fuse Block - Underhood
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> Component Information > Locations > Fuel Pump Relay > Page 6408
Locations View
The Fuel Pump (FP) Relay is located in the Underhood Fuse Block. The Underhood Fuse Block is
located at the left side of the engine compartment near the battery.
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> Component Information > Locations > Fuel Pump Relay > Page 6409
Fuel Pump Relay: Locations Fuel Pump Relay Secondary - With Dual Tanks
SECONDARY FUEL PUMP RELAY (With Dual Tanks Only)
Locations View
The Secondary Fuel Pump (FP) Relay (1) is attached to the Underhood Fuse Block on bracket.
The Underhood Fuse Block is located at the left side of the engine compartment near the battery.
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> Component Information > Locations > Fuel Pump Relay > Page 6410
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> Component Information > Diagrams > Diagram Information and Instructions
Fuel Pump Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6413
Electrical Symbols Part 1
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6414
Electrical Symbols Part 2
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6415
Electrical Symbols Part 3
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6416
Electrical Symbols Part 4
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6417
Fuel Pump Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6418
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6420
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6424
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6425
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6426
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6427
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6428
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6429
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6430
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6431
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6434
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6435
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6436
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6437
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Component Information > Diagrams > Diagram Information and Instructions > Page 6438
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pump Relay
> Component Information > Diagrams > Diagram Information and Instructions > Page 6441
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pump Relay
> Component Information > Diagrams > Diagram Information and Instructions > Page 6442
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump > Fuel Pump Relay
> Component Information > Diagrams > Diagram Information and Instructions > Page 6443
Fuel Pump (FP) Relay-Secondary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Pump Pickup Filter >
Component Information > Description and Operation
Fuel Pump Pickup Filter: Description and Operation
FUEL STRAINER
The fuel strainer attaches to the lower end of the fuel sender. The fuel strainer is made of woven
plastic. The functions of the fuel strainer are to filter contaminants and to wick fuel. The fuel strainer
is self-cleaning and normally requires no maintenance. Fuel stoppage at this point indicates that
the fuel tank contains an abnormal amount of sediment or water.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Description and Operation
Fuel Rail: Description and Operation
Fuel Rail Assembly
The fuel rail assembly attaches to the engine intake manifold. The fuel rail assembly performs the
following functions:
^ Positions the injectors (3) in the intake manifold
^ Distributes fuel evenly to the injectors
^ Integrates the fuel pressure regulator (2) with the fuel metering system
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement
Fuel Rail: Service and Repair Fuel Rail Assembly Replacement
REMOVAL PROCEDURE
IMPORTANT: An eight-digit identification number (1) is located on the fuel rail. Refer to this model
identification number if service or part replacement is required.
1. Remove the engine sight shield. 2. Before removal, if necessary, clean the fuel rail assembly
with a spray type engine cleaner, use GM X-30A or equivalent. Follow the package
instructions. Do not soak fuel rail assembly in any liquid cleaning solvents.
3. Disconnect the accelerator control and cruise control cables from the cable bracket, if equipped.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6452
4. Disconnect the cruise control cable engine-end fitting from the stud on the throttle lever, if
equipped.
5. Disconnect the accelerator control cable from the throttle lever, if equipped.
6. Remove the upper engine wire harness retainer nut. 7. Disconnect the evaporative emission
(EVAP) purge solenoid electrical connector. 8. Reposition the upper engine wire harness aside. 9.
Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6453
10. Mark the electrical connectors to their corresponding injectors to ensure correct sequential
injector firing order after reassembly.
IMPORTANT: When disconnecting the Multec (R) 2 fuel injector connectors, DO NOT use pliers or
other hand tools, as the connector ends may become mangled and be rendered unusable.
11. Pull the connector position assurance (CPA) (2) on the injector connector up. 12. Push the tab
(1) on the injector connector in.
13. While pushing the tab (1) on the injector connector in, release the CPA (2). 14. Disconnect the
fuel injector connector electrical connector. 15. Repeat the steps for each injector connector.
NOTE: ^
Remove the fuel rail assembly carefully in order to prevent damage to the injector electrical
connector terminals and the injector spray tips. Support the fuel rail after the fuel rail is removed in
order to avoid damaging the fuel rail components.
^ Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and
other contaminants from entering open pipes and passages.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6454
16. Disconnect the fuel feed and return pipes (1, 2) from the fuel rail. 17. Disconnect the fuel
pressure regulator vacuum line.
18. Loosen the retaining clip attaching screw (22) at the right hand fuel rail.
19. Remove the fuel rail bolts. 20. Remove the fuel rail.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6455
21. Remove and discard the fuel injector lower O-ring seals (4) from the injectors (3).
INSTALLATION PROCEDURE
1. Lubricate the NEW fuel injector lower O-ring seals (4) with clean engine oil. 2. Install the NEW
O-ring seals (4) to the end of each fuel injector (3).
3. Remove the retaining clip attaching screw (22) and crossover pipe retainer (21) to the right hand
fuel rail. 4. Remove the crossover pipe rail (25) from the right fuel rail (15). 5. Remove the
crossover pipe O-ring (20). 6. Lubricate a NEW O-ring (20) with clean engine oil. 7. Install a NEW
crossover pipe O-ring (20) on the crossover pipe (25). 8. Install the crossover pipe (25) into the
right fuel rail (15).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6456
IMPORTANT: When installing the retaining clip attaching screw for the crossover pipe, always start
the screw by hand. This will prevent consequent stripping of the threads in the fuel rail.
9. Loosely install the crossover pipe retainer (21) and retaining clip attaching screw (22) to the right
hand fuel rail.
10. Install the fuel rail. 11. Apply a 5 mm (0.020 in) band of GM P/N 12345382 threadlock, or
equivalent, to the threads of the fuel rail bolts.
NOTE: Refer to the Fastener Notice Cautions and Notices.
12. Install the fuel rail bolts.
Tighten 12.1. Tighten the bolts to 10 N.m (89 lb in). 12.2. Tighten the screw to 3.8 N.m (34 lb in).
13. Connect the fuel pressure regulator vacuum line. 14. Connect the fuel feed and return pipes (1,
2) to the fuel rail. 15. Connect the fuel injector electrical connectors.
^ Install each electrical connector onto the correct fuel injector in order to ensure correct sequential
injector firing order.
^ Rotate the fuel injectors as required in order to avoid stretching the wire harness.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6457
16. Position the upper engine wire harness in place. 17. Connect the EVAP purge solenoid
electrical connector. 18. Install the retainer nut to the upper engine wire harness.
Tighten Tighten the nut to 5.5 N.m (49 lb in).
19. Connect the accelerator control and cruise control cables to the cable bracket, if equipped.
20. Connect the accelerator control cable to the throttle body, if equipped.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6458
21. Connect the cruise control cable engine-end fitting to the stud on the throttle lever, if equipped.
22. Use the following procedure in order to inspect for leaks:
22.1. Turn ON the ignition, with the engine OFF, for 2 seconds. 22.2. Turn OFF the ignition for 10
seconds. 22.3. Turn ON the ignition, with the engine OFF. 22.4. Inspect for fuel leaks.
23. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6459
Fuel Rail: Service and Repair Fuel Rail Crossover Pipe Replacement
REMOVAL PROCEDURE
IMPORTANT: The fuel rail for the 5.3L regular production option (RPO) L59 (VIN Z) is compatible
with fuel that has a composition of up to 85 percent Ethanol (E85). Because of this the fuel rail will
be serviced as an entire assembly that includes both left and right rail assemblies and the
crossover pipe rail.
1. Remove the engine sight shield. 2. Relieve the fuel system pressure. Refer to Fuel Pressure
Relief Procedure. 3. Disconnect the fuel feed (1) and fuel return (2) pipes from the fuel rail.
4. Remove the fuel return pipe attaching screw (3) and the fuel return pipe retainer (2). 5. Remove
the fuel return pipe (1). 6. Remove and discard the fuel return pipe O-ring (6). 7. Remove the fuel
pressure connection core assembly (24) from the crossover pipe rail (25). 8. Remove the retaining
clip attaching screw (22) and the crossover fuel pipe retainer clip (21). 9. Remove the retaining clip
attaching screw (4) and the crossover fuel pipe retainer clip (5).
10. Remove the crossover pipe rail assembly (25) from the left hand rail assembly (14) and the
right hand rail assembly (15). 11. Remove and discard the crossover fuel pipe O-rings (7, 20).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6460
1. Lubricate the NEW crossover fuel pipe O-rings (7, 20) with clean engine oil. 2. Install the NEW
crossover fuel pipe O-rings (7, 20) onto the crossover pipe rail assembly (25). 3. Install the
crossover pipe rail assembly (25) to the left hand rail assembly (14) and the right hand rail
assembly (15).
NOTE: Refer to Fastener Notice in Service Precautions.
IMPORTANT: When installing the retaining clip attaching screws for the crossover pipe, always
start them by hand. This will prevent consequent stripping of the threads in the rail.
4. Install the crossover fuel pipe retainer clip (21). Loosely install the retaining clip attaching screw
(22). 5. Lubricate the NEW fuel return pipe O-ring (6) with clean engine oil. 6. Install the NEW fuel
return pipe O-ring (6) on the fuel return pipe (1). 7. Install the fuel return pipe (1). 8. Install the fuel
return pipe retainer (2). Loosely install the fuel return pipe attaching screw (3).
IMPORTANT: When installing the retaining clip attaching screws for the crossover pipe, always
start them by hand. This will prevent consequent stripping of the threads in the rail.
9. Install the crossover fuel pipe retainer clip (5). Loosely install the retaining clip attaching screw
(4).
Tighten 9.1.
Tighten the crossover fuel pipe retainer clip attaching screws (4, 22) to 3.8 N.m (34 lb in).
9.2. Tighten the fuel return pipe attaching screw (3) to 5 N.m (44 lb in).
10. Install the fuel pressure connection core assembly (24) to the crossover pipe rail assembly (25).
11. Connect the fuel return (2) and fuel feed (1) pipes to the fuel rail. 12. Tighten the fuel fill cap.
13. Connect the negative battery cable. 14. Use the following procedure in order to inspect for
leaks:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6461
14.1. Turn ON the ignition, with the engine OFF, for 2 seconds. 14.2. Turn OFF the ignition for 10
seconds. 14.3. Turn ON the ignition, with the engine OFF. 14.4. Inspect for fuel leaks.
15. Install the fuel pressure connection cap. 16. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6462
Fuel Rail: Service and Repair Fuel Rail Outlet Pipe Replacement
REMOVAL PROCEDURE
IMPORTANT: The fuel rail for the 5.3L regular production option (RPO) L59 (VIN Z) is compatible
with fuel that has a composition of up to 85 percent Ethanol (E85). Because of this the fuel rail will
be serviced as an entire assembly that includes both left and right rail assemblies and the fuel
return pipe.
1. Remove the engine sight shield. 2. Relieve the fuel system pressure. Refer to the Fuel Pressure
Relief Procedure. 3. Disconnect the fuel feed (1) and fuel return (2) pipes from the fuel rail.
4. Remove the retaining clip attaching screw (4). 5. Remove the crossover fuel pipe retainer clip
(5). 6. Remove the fuel return pipe attaching screw (3) and the fuel return pipe retainer (2). 7.
Remove the fuel return pipe (1). 8. Remove and discard the fuel return pipe O-ring (6).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Rail > Component
Information > Service and Repair > Fuel Rail Assembly Replacement > Page 6463
1. Lubricate a NEW fuel return pipe O-ring (6) with clean engine oil. 2. Install the fuel return pipe
O-ring (6) onto the fuel return pipe (1). 3. Install the fuel return pipe (1).
NOTE: Refer to the Fastener Notice in Service Precautions.
4. Install the fuel return pipe retainer (2) and the fuel return pipe attaching screw (3). 5. Install the
crossover fuel pipe retainer clip (5).
IMPORTANT: When installing the retaining clip attaching screw for the crossover pipe, always start
the screw by hand. This will prevent consequent stripping of the threads in the rail.
6. Install the retaining clip attaching screw (4).
Tighten 6.1.
Tighten the crossover fuel pipe retainer clip attaching screw (4) to 3.8 N.m (34 lb in).
6.2. Tighten the fuel return pipe attaching screw (3) to 5 N.m (44 lb in).
7. Connect the fuel return (2) and the fuel feed (1) pipes to the fuel rail. 8. Tighten the fuel filler cap.
9. Connect the negative battery cable.
10. Use the following procedure in order to inspect for leaks:
10.1. Turn ON the ignition, with the engine OFF, for 2 seconds. 10.2. Turn OFF the ignition for 10
seconds. 10.3. Turn ON the ignition, with the engine OFF. 10.4. Inspect for fuel leaks.
11. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Description and Operation > Fuel Feed and Return Pipes
Fuel Supply Line: Description and Operation Fuel Feed and Return Pipes
The fuel feed pipe carries fuel from the fuel tank to the fuel rail assembly. The fuel return pipe
carries fuel from the fuel rail assembly back to the fuel tank. The fuel pipes consist of 2 sections:
^ The rear fuel pipe assemblies are located from the top of the fuel tank to the chassis fuel pipes.
The rear fuel pipes are constructed of nylon.
^ The chassis fuel pipes are located under the vehicle and connect the rear fuel pipes to the fuel
rail pipes. These pipes are constructed of steel with sections of rubber hose covered with braiding.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Description and Operation > Fuel Feed and Return Pipes > Page 6468
Fuel Supply Line: Description and Operation Nylon Fuel Pipes
CAUTION: Refer to Fuel and EVAP Pipe Caution in Service Precautions.
Nylon pipes are constructed to withstand maximum fuel system pressure, exposure to fuel
additives, and changes in temperature. There are 3 sizes of nylon pipes used: 9.5 mm (3/8 in.) ID
for the fuel feed, 7.6 mm (5/16 in.) ID for the fuel return, and 12.7 mm (1/2 in.) ID for the vent. Heat
resistant rubber hose or corrugated plastic conduit protect the sections of the pipes that are
exposed to chafing, to high temperatures, or to vibration.
Nylon fuel pipes are somewhat flexible and can be formed around gradual turns under the vehicle.
However, if nylon fuel pipes are forced into sharp bends, the pipes kink and restrict the fuel flow.
Also, once exposed to fuel, nylon pipes may become stiffer and are more likely to kink if bent too
far. Take special care when working on a vehicle with nylon fuel pipes.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Description and Operation > Fuel Feed and Return Pipes > Page 6469
Fuel Supply Line: Description and Operation Fuel Pipe O-Rings
O-rings seal the threaded connections in the fuel system. Fuel system O-ring seals are made of
special material. Service the O-ring seals with the correct service part.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis
Fuel Supply Line: Service and Repair Fuel Hose/Pipes Replacement - Chassis
REMOVAL PROCEDURE
1. Relieve the fuel system pressure. Refer to the Fuel Pressure Relief Procedure. 2. Clean all the
fuel pipe connections and the surrounding areas before disconnecting the pipes in order to avoid
possible contamination of the fuel
system.
3. Disconnect the fuel feed and return pipes (1, 2) from the fuel rail. 4. Cap the fuel rail pipes. 5.
Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 6. Remove the fuel pipes from the
bellhousing stud clip (4). 7. Remove the fuel pipes from the transmission bracket clip.
8. Remove the fuel pipes from the transfer case bracket clip, 4-wheel drive only.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis > Page 6472
9. Remove the evaporative emission (EVAP) canister from the vehicle.
10. Disconnect the chassis fuel feed and return pipes at the rear fuel feed and return pipes. 11.
Cap the rear fuel pipes.
12. Note the position of the fuel pipes for aid in installation. 13. Remove the fuel pipes from the
retaining clips (1). 14. Remove the fuel pipes.
INSTALLATION PROCEDURE
IMPORTANT:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis > Page 6473
^ When replacing the fuel pipes, always replace them with original equipment or parts that meet the
GM specifications for those parts. The replacement pipes must have the same type of fittings as
the original pipes in order to ensure the integrity of the connection.
^ DO NOT use copper or aluminum tubing to replace steel tubing. Only tubing meeting the 124-M
specification or the equivalent is capable of meeting all pressure, corrosion and vibration
characteristics necessary to ensure the durability standard required.
1. Install the fuel pipes into the retaining clips (1).
2. Remove the caps from the rear fuel pipes. 3. Connect the chassis fuel feed and return pipes at
the rear fuel feed and return pipes.
4. Install the EVAP canister.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis > Page 6474
5. Install the fuel pipes into the transfer case bracket clip, 4 wheel drive only.
6. Install the fuel pipes into the transmission bracket clip. 7. Install the fuel pipes into the
bellhousing stud clip (4). 8. Lower the vehicle. 9. Remove the caps from the fuel rail pipes.
10. Connect the fuel feed and return pipes (1, 2) to the fuel rail. 11. Tighten the fuel filler cap. 12.
Connect the negative battery cable. 13. Use the following procedure in order to inspect for leaks:
13.1. Turn ON the ignition, with the engine OFF, for 2 seconds. 13.2. Turn OFF the ignition for 10
seconds. 13.3. Turn ON the ignition, with the engine OFF. 13.4. Inspect for fuel leaks.
14. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis > Page 6475
Fuel Supply Line: Service and Repair Fuel Hose/Pipes Assembly Replacement
REMOVAL PROCEDURE
1. Clean all the fuel pipe and hose connections and the surrounding areas before disconnecting in
order to avoid possible contamination of the fuel
system.
2. Remove the fuel tank. 3. Remove the rear fuel feed pipe (4) and the rear fuel return pipe (5) from
the fuel sender (2) and the fuel tank clips (6). 4. Cap the fuel pipes in order to prevent possible fuel
system contamination.
INSTALLATION PROCEDURE
1. Remove the caps from the fuel pipes. 2. Connect the rear fuel feed pipe (4) and the rear fuel
return pipe (5) to the fuel sender (2) and the fuel tank clips (6).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Supply Line > Component
Information > Service and Repair > Fuel Hose/Pipes Replacement - Chassis > Page 6476
3. Install the fuel tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks)
Fuel Filler Hose: Service and Repair Filler Tube Replacement (Dual Tanks)
REMOVAL PROCEDURE
1. Drain the fuel below the level of the fuel filler hose. Refer to Fuel Tank Draining Procedure
(Utility Single Tank) or Fuel Tank Draining
Procedure (Utility Dual Tank Front) or Fuel Tank Draining Procedure (Utility Dual Tank Rear).
2. Remove the fuel fill pipe housing to fuel fill pipe bolts. 3. Raise the vehicle. Refer to Lifting and
Jacking the Vehicle.
4. Disconnect the fuel fill pipe ground strap.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6482
5. Disconnect the rear axle vent hose from the retainer on the fuel fill pipe. 6. Loosen the fuel vent
hose (3) to fill tube clamp (2). 7. Disconnect the fuel vent hose (3) from the fill tube.
8. Loosen the fuel fill hose to fuel tank clamp (2). 9. Disconnect the fuel fill hose from the fuel tank.
10. Remove the fuel fill hose assembly. 11. Cap the open end of the fuel tank.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6483
1. Uncap the fuel tank.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the fuel fill hose assembly to the fuel tank.
Tighten Tighten the fuel fill pipe clamp (2) to 2.5 N.m (22 lb in).
3. Connect the fuel fill vent hose (3) to the fill tube.
Tighten Tighten the vent hose clamp (2) to 2.5 N.m (22 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6484
4. Connect the fuel fill pipe ground strap.
Tighten Tighten the fuel fill pipe ground strap bolt to 9 N.m (80 lb in).
5. Connect the rear axle vent hose to the retainer on the fuel fill pipe. 6. Lower the vehicle.
7. Install the fuel fill pipe housing to the fuel fill pipe bolts.
Tighten Tighten the fuel fill pipe housing to fuel fill pipe bolts to 2.3 N.m (20 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6485
Fuel Filler Cap
8. Refill the fuel system. 9. Install the fuel filler cap.
10. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6486
Fuel Filler Hose: Service and Repair Filler Tube Replacement (Single Tank)
REMOVAL PROCEDURE
Fuel Filler Cap
1. Clean all the fuel pipe and hose connections and the surrounding areas before disconnection in
order to avoid possible contamination of the fuel
system.
2. Remove the fuel filler cap. 3. Drain the fuel below the level of the fuel filler hose. Refer to Fuel
Tank Draining Procedure (Utility Single Tank) or Fuel Tank Draining
Procedure (Utility Dual Tank Front) or Fuel Tank Draining Procedure (Utility Dual Tank Rear).
4. Remove the fuel fill pipe housing to fuel fill pipe bolts. 5. Raise the vehicle. Refer to Lifting and
Jacking the Vehicle. 6. Remove spare tire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6487
7. Disconnect the fuel fill pipe ground strap (3).
8. Disconnect the rear axle vent hose from the retainer on the fuel fill pipe, if applicable. 9. Loosen
the fuel vent hose to fuel tank clamp (1).
10. Loosen the fuel fill hose to fuel tank clamp (11). 11. Disconnect the fuel fill pipe bracket bolt (3).
12. Disconnect the fuel fill and vent hoses from the fuel tank. 13. Remove the fuel fill and vent pipe
and hose assembly. 14. Cap the open end of the fuel tank.
INSTALLATION PROCEDURE
1. Uncap the fuel tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6488
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the fuel fill and vent pipe hose assembly to the fuel tank.
Tighten Tighten the vent hose clamp (1) and the fuel fill pipe clamp (11) to 2.5 N.m (22 lb in)
3. Install the fuel fill pipe bracket bolt (3).
Tighten Tighten the bolt to 12 N.m (106 lb in).
4. Connect the fuel fill pipe ground strap (3).
Tighten Tighten the fuel fill pipe ground strap bolt to 9 N.m (80 lb in).
5. Connect the rear axle vent hose to the retainer on the fuel fill pipe, if applicable. 6. Install spare
tire. 7. Lower the vehicle.
8. Install the fuel fill pipe housing to the fuel fill pipe bolts.
Tighten Tighten the fuel fill pipe housing to fuel fill pipe bolts to 2.3 N.m (20 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6489
Fuel Filler Cap
9. Refill the fuel system.
10. Install the fuel filler cap.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6490
Fuel Filler Hose: Service and Repair Fuel Filler Hose Replacement
REMOVAL PROCEDURE
1. Clean all the fuel pipe and hose connections and the surrounding areas before disconnecting in
order to avoid possible contamination of the fuel
system.
2. Drain the fuel below the level of the filler tube and hose assembly. Refer to Fuel Tank Draining
Procedure (Utility Single Tank) or Fuel Tank
Draining Procedure (Utility Dual Tank Front) or Fuel Tank Draining Procedure (Utility Dual Tank
Rear)
3. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 4. Disconnect the fuel fill hose clamp
(11) at the fuel tank. 5. Disconnect the fuel fill hose clamp (2) at the fuel till pipe. 6. Remove the fuel
fill hose and the hose clamps (11, 2). 7. Disconnect the fuel till hose clamp (8) at the fill pipe. 8.
Disconnect the fuel fill hose clamp (10) at the fill pipe. 9. Remove the fuel till hose and the hose
clamps (8, 10).
10. Cap the fuel tank opening.
INSTALLATION PROCEDURE
1. Uncap the fuel tank opening. 2. Install the fuel fill hose and the hose clamps (8,10) to the fuel fill
pipe. 3. Install the fuel fill hose and the hose clamps (2,11) to the fuel fill pipe.
NOTE: Refer to Fastener Notice in Service Precautions.
Tighten Tighten the hose clamps to 2.5 N.m (22 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Filler Hose >
Component Information > Service and Repair > Filler Tube Replacement (Dual Tanks) > Page 6491
4. Lower the vehicle. 5. Refill the fuel system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Fuel Gauge Sender: Customer Interest Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Bulletin No.: 04-08-49-018E
Date: January 05, 2005
TECHNICAL
Subject: Cranks But No Start, Stall, Inaccurate/Incorrect Fuel Gauge Reading, No Fuel, Vehicle is
Out of Fuel and Fuel Gauge Reads Above Empty (Replace Fuel Level Sensor)
Models: 2001-2004 Cadillac Trucks 1999-2004 Chevrolet and GMC Trucks
with Gasoline Engine (VINs Z, X, V, T, U, N, G, 6, 8 - RPOs LU3, LR4, LM7, LQ4, LQ9, L59,
L18,LK5 L52)
Attention:
Parts are currently available for vehicles with Variable Fuel (VIN Z - RPO L59) vehicles. Please
refer to Corporate Bulletin Number 04-06-04-01 2B or newer for Variable Fuel (VIN Z - RPO L59)
vehicles.
Supercede:
This bulletin is being revised to include information on the Chevrolet Colorado and the GMC
Canyon. Please discard Corporate Bulletin Number 04-08-49-018D (Section 08 - Body and
Accessories).
Condition
Some customers may comment on the vehicle stalling and will not restart, vehicle ran out of fuel,
vehicle appears to be out of fuel but the fuel gauge reads above empty. The fuel gauge may read
1/4 tank.
Cause
Contamination on the fuel sending card may cause inaccurate/incorrect fuel gauge readings.
Correction
Follow the service procedure below for diagnosis and repair of this concern.
1. Confirm that the vehicle is actually out of fuel.
^ If the vehicle is not out of fuel but Engine Cranks but Does Not Run, refer to the appropriate
Service Information.
^ If the vehicle is out of fuel and the gauge does not read empty, test the fuel gauge. Refer to the
following information:
- Fuel Gage Inaccurate or Inoperative Single Tank
- Fuel Gage Inaccurate or Inoperative Dual Tanks
- Fuel Gage Inaccurate or Inoperative Colorado and Canyon
2. If testing reveals that the fuel gauge is operating correctly, replace the fuel sensor assembly and
auxiliary tank fuel level sensor if equipped.
3. Replace the fuel level sensor. Refer to the following appropriate service information:
^ Fuel Level Sensor Replacement 4.8L and 5.3L Engines
^ Fuel Level Sensor Replacement 6.0L Engine - Front Tank
^ Fuel Level Sensor Replacement 6.0L Engine - Rear Tank
^ Fuel Level Sensor Replacement 8.1L vehicles with Front Tank
^ Fuel Level Sensor Replacement 8.1 L vehicles with Rear Tank
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 6500
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Customer Interest for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 6501
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge
Fuel Gauge Sender: All Technical Service Bulletins Fuel System - Cranks But No Start/Inaccurate
Fuel Gauge
Bulletin No.: 04-08-49-018E
Date: January 05, 2005
TECHNICAL
Subject: Cranks But No Start, Stall, Inaccurate/Incorrect Fuel Gauge Reading, No Fuel, Vehicle is
Out of Fuel and Fuel Gauge Reads Above Empty (Replace Fuel Level Sensor)
Models: 2001-2004 Cadillac Trucks 1999-2004 Chevrolet and GMC Trucks
with Gasoline Engine (VINs Z, X, V, T, U, N, G, 6, 8 - RPOs LU3, LR4, LM7, LQ4, LQ9, L59,
L18,LK5 L52)
Attention:
Parts are currently available for vehicles with Variable Fuel (VIN Z - RPO L59) vehicles. Please
refer to Corporate Bulletin Number 04-06-04-01 2B or newer for Variable Fuel (VIN Z - RPO L59)
vehicles.
Supercede:
This bulletin is being revised to include information on the Chevrolet Colorado and the GMC
Canyon. Please discard Corporate Bulletin Number 04-08-49-018D (Section 08 - Body and
Accessories).
Condition
Some customers may comment on the vehicle stalling and will not restart, vehicle ran out of fuel,
vehicle appears to be out of fuel but the fuel gauge reads above empty. The fuel gauge may read
1/4 tank.
Cause
Contamination on the fuel sending card may cause inaccurate/incorrect fuel gauge readings.
Correction
Follow the service procedure below for diagnosis and repair of this concern.
1. Confirm that the vehicle is actually out of fuel.
^ If the vehicle is not out of fuel but Engine Cranks but Does Not Run, refer to the appropriate
Service Information.
^ If the vehicle is out of fuel and the gauge does not read empty, test the fuel gauge. Refer to the
following information:
- Fuel Gage Inaccurate or Inoperative Single Tank
- Fuel Gage Inaccurate or Inoperative Dual Tanks
- Fuel Gage Inaccurate or Inoperative Colorado and Canyon
2. If testing reveals that the fuel gauge is operating correctly, replace the fuel sensor assembly and
auxiliary tank fuel level sensor if equipped.
3. Replace the fuel level sensor. Refer to the following appropriate service information:
^ Fuel Level Sensor Replacement 4.8L and 5.3L Engines
^ Fuel Level Sensor Replacement 6.0L Engine - Front Tank
^ Fuel Level Sensor Replacement 6.0L Engine - Rear Tank
^ Fuel Level Sensor Replacement 8.1L vehicles with Front Tank
^ Fuel Level Sensor Replacement 8.1 L vehicles with Rear Tank
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 6507
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Fuel Gauge Sender: >
04-08-49-018E > Jan > 05 > Fuel System - Cranks But No Start/Inaccurate Fuel Gauge > Page 6508
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6509
Fuel Gauge Sender: Specifications
Fuel Level Specifications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6510
Fuel Level Specifications Part 2
The values in the table are approximate values based on information obtained from properly
operating vehicles. Actual results may vary slightly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6511
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6512
Fuel Gauge Sender: Diagrams
Fuel Pump/Sender - Secondary
Fuel Pump/Sender - Primary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6513
Fuel Gauge Sender: Description and Operation
Fuel Level Sensor
The fuel level sensor consists of a float, a wire float arm, and a ceramic resistor cord. The position
of the float arm indicates the fuel level. The fuel level sensor contains a variable resistor, which
changes resistance in correspondence to the amount of fuel in the fuel tank. The Powertrain
Control Module (PCM) sends the fuel level information via the class 2 circuit to the Instrument
Panel (IP) cluster. This information is used for the IP fuel gauge and the low fuel warning indicator,
if applicable. The PCM also monitors the fuel level input for various diagnostics.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank > Fuel Gauge
Sender > Component Information > Technical Service Bulletins > Page 6514
Fuel Gauge Sender: Service and Repair
REMOVAL PROCEDURE
1. Remove the fuel sender assembly. 2. Disconnect the fuel pump electrical connector (5). 3.
Remove the retaining clip (6) from the fuel level sensor connector. 4. Disconnect the electrical
connector (7) from under the fuel sender cover. 5. Remove the sensor retaining clip (4). 6.
Squeeze the locking tangs and remove the fuel level sensor (3).
INSTALLATION PROCEDURE
1. Install the fuel level sensor (3). 2. Install the sensor retaining clip (4). 3. Connect the electrical
connector (7) to the fuel level sensor. 4. Connect the retaining clip (6) to the fuel level sensor
electrical connector. 5. Connect the fuel pump electrical connector (5). 6. Install the fuel sender
assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank Unit > Component
Information > Diagrams
Fuel Tank Unit: Diagrams
Fuel Pump And Sender-Secondary
Fuel Pump And Sender-Primary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank Unit > Component
Information > Diagrams > Page 6518
Fuel Tank Unit: Service and Repair
Fuel Sender Assembly Replacement
Tool Required J44402 Fuel Tank Sending Unit Wrench.
Removal Procedure
1. Remove the fuel tank. 2. Remove fuel lines from sender assembly.
3. Remove the fuel sender assembly retaining ring using the J 44402. 4. Remove the fuel sender
assembly and the seal. Discard the seal.
Caution: Drain the fuel from the fuel sender assembly into an approved container in order to reduce
the risk of fire and personal injury. Never store the fuel in an open container.
5. Clean the fuel sender sealing surfaces.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Fuel Tank Unit > Component
Information > Diagrams > Page 6519
Caution: Drain the fuel from the fuel sender assembly into an approved container in order to reduce
the risk of fire and personal injury. Never store the fuel in an open container.
1. Install the new seal on the fuel tank.
Important: The fuel pump strainer must be in a horizontal position when the fuel sender is installed
in the tank. When installing the fuel sender assembly, assure that the fuel pump strainer does not
block full travel of the float arm.
2. Install the fuel sender assembly into the fuel tank.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct
part number for that application. Fasteners requiring replacement or fasteners requiring the use of
thread locking compound or sealant are identified in the service procedure. Do not use paints,
lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These
coatings affect fastener torque and joint clamping force and may damage the fastener. Use the
correct tightening sequence and specifications when installing fasteners in order to avoid damage
to parts and systems.
3. Install the fuel sender assembly retaining ring using the J 44402. 4. Install fuel lines to sender
assembly.. 5. Install the fuel tank.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6523
Idle Air Control (IAC) Valve
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6524
Idle Speed/Throttle Actuator - Electronic: Testing and Inspection
CIRCUIT DESCRIPTION
The engine idle speed is controlled by the idle air control (IAC) valve. The IAC valve is on the
throttle body. The IAC valve pintle moves in and out of an idle air passage bore to control air flow
around the throttle plate. The valve consists of a movable pintle, driven by a gear attached to a two
phase bi-polar permanent magnet electric motor called a stepper motor. The stepper motor is
capable of highly accurate rotation, or of movement, called steps. The stepper motor has two
separate windings that are called coils. Each coil is fed by two circuits from the powertrain control
module (PCM). When the PCM changes polarity of a coil, the stepper motor moves one step. The
PCM uses a predetermined number of counts to determine the IAC pintle position. Observe IAC
counts with a scan tool. The IAC counts will increment up or down as the PCM attempts to change
the IAC valve pintle position. An IAC Reset will occur when the ignition key is turned OFF. First, the
PCM will seat the IAC pintle in the idle air passage bore. Second, the PCM will retract the pintle a
predetermined number of counts to allow for efficient engine start-up. If the engine idle speed is out
of range for a calibrated period of time, an idle speed diagnostic trouble code (DTC) may set.
DIAGNOSTIC AIDS
Inspect for the following conditions: ^
A skewed high throttle position (TP) sensor
^ Restricted air intake system
^ Objects blocking the IAC passage or throttle bore
^ The correct positive crankcase ventilation (PCV) valve
^ A properly installed PCV valve
^ Proper operation of the PCV valve
^ Proper operation and installation of all air intake components
^ Proper installation and operation of the mass air flow (MAF) sensor, if equipped
^ Evidence of damage or tampering of the following components: The throttle stop screw
- The throttle plate
- The throttle shaft
- The throttle linkage
- The cruise control linkage-if equipped
^ Excess deposits in the IAC passage or on the IAC pintle
^ Excess deposits in the throttle bore or on the throttle plate
^ Vacuum leaks
^ Excess load on engine, such as energy-draining conditions of the transmission, power steering,
or alternator
^ A high or unstable idle condition-This condition could be caused by a non-IAC system problem
that can not be overcome by the IAC valve. Refer to Symptoms - Computers and Controls
Systems. See: Computers and Control Systems/Testing and Inspection/Symptom Related
Diagnostic Procedures
^ A low or unstable idle condition-This condition could be caused by a non-IAC system problem
that can not be overcome by the IAC valve. Refer to Symptoms - Computers and Controls
Systems. See: Computers and Control Systems/Testing and Inspection/Symptom Related
Diagnostic Procedures
^ An intermittent condition-If the condition is intermittent, refer to Intermittent Conditions. See:
Computers and Control Systems/Testing and Inspection/Initial Inspection and Diagnostic
Overview/Intermittent Conditions
TEST DESCRIPTION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6525
Steps 1-6
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6526
Steps 7-11
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6527
Steps 12-19
The numbers below refer to the step numbers on the diagnostic table. 5. This test will determine
the ability of the PCM and IAC valve circuits to control the IAC valve. 7. This test will determine the
ability of the PCM to provide the IAC valve circuits with a ground. On a normally operating system,
the test lamp
should not flash while the IAC counts are incrementing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6528
Idle Speed/Throttle Actuator - Electronic: Service and Repair
IDLE AIR CONTROL (IAC) VALVE REPLACEMENT
REMOVAL PROCEDURE
1. Disconnect the idle air control (IAC) valve electrical connector
2. Remove the IAC valve attaching screws (4). 3. Remove the IAC valve (3). 4. Remove the IAC
valve O-ring seal (2).
NOTE: ^
Do Not push or pull on the IAC valve pintle on IAC valves that have been in service. The force
required to move the pintle may damage the threads on the worm drive.
^ Do Not soak the IAC valve in any liquid cleaner or solvent, as damage may result.
5. Clean the IAC valve O-ring sealing surface, the pintle valve seat, and the air passage.
^ Clean the IAC valve using GM cleaner P/N 1052626 or GM X-66A. Use a shop towel or parts
brush to remove heavy deposits.
^ If the air passage has heavy deposits, remove the throttle body for complete cleaning.
^ Shiny spots on the pintle or seat are normal and do not indicate misalignment or a bent pintle
shaft.
6. Inspect the IAC valve O-ring for cuts, cracks, or distortion. Replace the O-ring if the O-ring is
damaged.
INSTALLATION PROCEDURE
IMPORTANT: If installing a new IAC valve, be sure to replace the IAC valve with an identical part.
The pintle shape of the IAC valve and the diameter of the IAC valve are designed for the specific
application.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Idle Speed/Throttle Actuator Electronic > Component Information > Locations > Page 6529
1. Measure the distance between the tip of the IAC valve pintle and the mounting surface (1). If the
distance is more than 28 mm (1.1 in) use finger
pressure to slowly retract the pintle. The force required to retract the pintle of a new valve does not
cause damage to the valve.
2. Lubricate the IAC valve O-ring (2) with clean engine oil. 3. Install the IAC valve O-ring (2) on the
IAC valve (3). 4. Install the IAC valve (3). 5. Apply LOCTITE 262 to the IAC valve attaching screw
threads if necessary.
NOTE: Refer to the Fastener Notice in Service Precautions.
6. Install the IAC valve attaching screws (4).
Tighten Tighten the screws to 3 N.m (27 lb in).
7. Connect the IAC valve electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Intake Air Plenum > Intake Air
Plenum Gasket > Component Information > Technical Service Bulletins > Customer Interest for Intake Air Plenum Gasket: >
05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300
Intake Air Plenum Gasket: Customer Interest Engine - Rough Idle/Misfire/MIL ON/DTC P0300
Bulletin No.: 05-06-04-029A
Date: June 24, 2005
TECHNICAL
Subject: Flexible Fuel (RPO L59) Rough Idle, Misfire, MIL DTC P0300 (Install Intake Manifold
Gaskets With Teal Green Gasket Material)
Models: 2002-2004 Chevrolet Silverado, Suburban, Tahoe 2002-2004 GMC Sierra, Yukon, Yukon
XL with 5.3L Engine and Flexible Fuel (VIN Z - RPO L59)
This bulletin may apply to the following engines using regular fuel: 4.8L, 5.3L, 6.0L (VINs V, T, P,
U, N - RPOs LR4, LM7, LM4, LQ4, LQ9).
Supercede:
This bulletin is being revised to add additional diagnostic information. Please discard Corporate
Bulletin Number 05-06-04-029 (Section 06 - Engine/Propulsion System).
Important:
Always begin your diagnosis with the Diagnostic System Check - Engine Controls (SI Document ID
# 1289827) for any MIL or driveability concern. The Diagnostic System Check directs you to the
next logical step in your diagnosis. Follow the instructions in this bulletin should the rough idle,
misfire, or DTC P0300 diagnostic procedure point to an air leak in the intake manifold gasket.
Following the published diagnostic procedures will improve diagnostic accuracy and support our fix
it right the first time approach.
Condition
Some customers may comment that the vehicle may have a rough idle, misfires and/or a MIL
illuminated with a stored DTC P0300.
Cause
The L59 engine is calibrated for ethanol fuel (E85). Due to the low volatility of ethanol, the PCM
provides higher fuel flow through the injector, which may pool on the upper manifold to head gasket
material. Overtime (usually 12 months and longer), the gasket material may degrade resulting in an
unmetered air leak.
Correction
Replace the upper intake manifold gaskets with the teal green gasket material, P/N 89017589.
Important:
Do not replace the upper intake manifold gaskets with the original orange gasket material, P/N
17113557.
Inspect Intake Manifold to Cylinder head Deck for Warpage
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Intake Air Plenum > Intake Air
Plenum Gasket > Component Information > Technical Service Bulletins > Customer Interest for Intake Air Plenum Gasket: >
05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300 > Page 6539
Important:
The intake plenum should also be checked for excessive warpage that may cause an uneven
clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced.
Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a
200 mm (7.87 in) area should be replaced." Intake warpage is measured at the gasket sealing
surfaces and should be measured within a 200 mm (7.87 in) area. This measurement is across
only two of the intake runner port openings. Measurements taken across the entire distance of all
four intake runner ports will lead to unnecessary manifold replacements.
Important:
Measurements taken across the entire distance of all four intake runner ports will lead to
unnecessary intake manifold replacements.
1. Locate a straight edge across the intake manifold cylinder head deck surface. Position the
straight edge across two runner port openings.
2. Insert a feeler gauge between the intake manifold and the straight edge. An intake manifold with
warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be
replaced. Do not replace intake manifolds with warpage that measures less than 3 mm (0.118 in)
over a 200 mm (7.87 in).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Intake Air Plenum > Intake Air
Plenum Gasket > Component Information > Technical Service Bulletins > Customer Interest for Intake Air Plenum Gasket: >
05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300 > Page 6540
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Intake Air Plenum > Intake Air
Plenum Gasket > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Intake Air
Plenum Gasket: > 05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300
Intake Air Plenum Gasket: All Technical Service Bulletins Engine - Rough Idle/Misfire/MIL ON/DTC
P0300
Bulletin No.: 05-06-04-029A
Date: June 24, 2005
TECHNICAL
Subject: Flexible Fuel (RPO L59) Rough Idle, Misfire, MIL DTC P0300 (Install Intake Manifold
Gaskets With Teal Green Gasket Material)
Models: 2002-2004 Chevrolet Silverado, Suburban, Tahoe 2002-2004 GMC Sierra, Yukon, Yukon
XL with 5.3L Engine and Flexible Fuel (VIN Z - RPO L59)
This bulletin may apply to the following engines using regular fuel: 4.8L, 5.3L, 6.0L (VINs V, T, P,
U, N - RPOs LR4, LM7, LM4, LQ4, LQ9).
Supercede:
This bulletin is being revised to add additional diagnostic information. Please discard Corporate
Bulletin Number 05-06-04-029 (Section 06 - Engine/Propulsion System).
Important:
Always begin your diagnosis with the Diagnostic System Check - Engine Controls (SI Document ID
# 1289827) for any MIL or driveability concern. The Diagnostic System Check directs you to the
next logical step in your diagnosis. Follow the instructions in this bulletin should the rough idle,
misfire, or DTC P0300 diagnostic procedure point to an air leak in the intake manifold gasket.
Following the published diagnostic procedures will improve diagnostic accuracy and support our fix
it right the first time approach.
Condition
Some customers may comment that the vehicle may have a rough idle, misfires and/or a MIL
illuminated with a stored DTC P0300.
Cause
The L59 engine is calibrated for ethanol fuel (E85). Due to the low volatility of ethanol, the PCM
provides higher fuel flow through the injector, which may pool on the upper manifold to head gasket
material. Overtime (usually 12 months and longer), the gasket material may degrade resulting in an
unmetered air leak.
Correction
Replace the upper intake manifold gaskets with the teal green gasket material, P/N 89017589.
Important:
Do not replace the upper intake manifold gaskets with the original orange gasket material, P/N
17113557.
Inspect Intake Manifold to Cylinder head Deck for Warpage
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Intake Air Plenum > Intake Air
Plenum Gasket > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Intake Air
Plenum Gasket: > 05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300 > Page 6546
Important:
The intake plenum should also be checked for excessive warpage that may cause an uneven
clamping pressure of the seal. If the plenum is found to be warped it will need to be replaced.
Service Information states, "An intake manifold with warpage in excess of 3 mm (0.118 in) over a
200 mm (7.87 in) area should be replaced." Intake warpage is measured at the gasket sealing
surfaces and should be measured within a 200 mm (7.87 in) area. This measurement is across
only two of the intake runner port openings. Measurements taken across the entire distance of all
four intake runner ports will lead to unnecessary manifold replacements.
Important:
Measurements taken across the entire distance of all four intake runner ports will lead to
unnecessary intake manifold replacements.
1. Locate a straight edge across the intake manifold cylinder head deck surface. Position the
straight edge across two runner port openings.
2. Insert a feeler gauge between the intake manifold and the straight edge. An intake manifold with
warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be
replaced. Do not replace intake manifolds with warpage that measures less than 3 mm (0.118 in)
over a 200 mm (7.87 in).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
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Plenum Gasket > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Intake Air
Plenum Gasket: > 05-06-04-029A > Jun > 05 > Engine - Rough Idle/Misfire/MIL ON/DTC P0300 > Page 6547
Disclaimer
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Relays and Modules - Fuel
Delivery and Air Induction > Fuel Pump Relay > Component Information > Locations > Fuel Pump Relay
Fuel Pump Relay: Locations Fuel Pump Relay
FUEL PUMP RELAY
Fuse Block - Underhood
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Locations > Fuel Pump Relay > Page 6553
Locations View
The Fuel Pump (FP) Relay is located in the Underhood Fuse Block. The Underhood Fuse Block is
located at the left side of the engine compartment near the battery.
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Fuel Pump Relay: Locations Fuel Pump Relay Secondary - With Dual Tanks
SECONDARY FUEL PUMP RELAY (With Dual Tanks Only)
Locations View
The Secondary Fuel Pump (FP) Relay (1) is attached to the Underhood Fuse Block on bracket.
The Underhood Fuse Block is located at the left side of the engine compartment near the battery.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
Fuel Pump Relay: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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> Page 6558
Electrical Symbols Part 1
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> Page 6559
Electrical Symbols Part 2
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6560
Electrical Symbols Part 3
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6561
Electrical Symbols Part 4
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> Page 6562
Fuel Pump Relay: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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> Page 6563
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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> Page 6566
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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> Page 6568
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6570
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6571
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6572
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6573
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6574
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6575
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6576
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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> Page 6577
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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> Page 6578
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6579
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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> Page 6580
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6581
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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> Page 6582
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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> Page 6583
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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> Page 6584
Equivalents - Decimal And Metric Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Relays and Modules - Fuel
Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6585
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Relays and Modules - Fuel
Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6586
Various symbols are used in order to describe different service operations.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Relays and Modules - Fuel
Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6587
Conversion - English/Metric
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Relays and Modules - Fuel
Delivery and Air Induction > Fuel Pump Relay > Component Information > Diagrams > Diagram Information and Instructions
> Page 6588
Fuel Pump (FP) Relay-Secondary
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Resonator, Intake Air >
Component Information > Service and Repair
Resonator: Service and Repair
REMOVAL PROCEDURE
1. Loosen the clamp and separate the air cleaner resonator outlet duct from the mass air
flow/intake air temperature (MAF/IAT) sensor assembly. 2. Loosen the clamp and separate the air
cleaner resonator outlet duct from the throttle body assembly. 3. Remove the air cleaner resonator
outlet duct.
INSTALLATION PROCEDURE
1. Install the air cleaner resonator outlet duct to the throttle body assembly and the MAF/IAT sensor
assembly. 2. Tighten the clamps at the throttle body assembly and the MAF/IAT sensor assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations > Page 6596
Accelerator Pedal Position (APP) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations > Page 6597
Accelerator Pedal Position Sensor: Description and Operation
Accelerator Pedal Position (APP) Sensor
The APP sensor is mounted on the accelerator pedal assembly. The APP is actually 3 individual
accelerator pedal position sensors within one housing. Three separate signal, low reference, and
5-volt reference circuits are used to connect the APP and the TAC module. The APP sensor 1
voltage should increase as the accelerator pedal is depressed, from below 1.0 volt at 0 pedal travel
to above 2.0 volts at 100 percent pedal travel. APP sensor 2 voltage should decrease from above
4.0 volts at 0 pedal travel to below 2.9 volts at 100 percent pedal travel. APP sensor 3 voltage
should decrease from above 3.8 volts at 0 percent pedal travel to below 3.1 volts at 100 percent
pedal travel.
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Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations > Page 6598
Accelerator Pedal Position Sensor: Service and Repair
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
1. Remove the left instrument panel (IP) lower closeout insulator panel.
2. Disconnect the accelerator pedal position (APP) sensor harness connector.
Remove the accelerator pedal mounting bolts.
3. Remove the APP assembly.
INSTALLATION PROCEDURE
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Delivery and Air Induction > Accelerator Pedal Position Sensor > Component Information > Locations > Page 6599
1. Install the APP assembly to the steering column support bracket.
NOTE: Refer to the Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
2. Install the accelerator pedal mounting bolts.
Tighten Tighten the accelerator pedal mounting bolts to 20 N.m (15 lb ft).
3. Connect the APP sensor harness connector. 4. Verify that the vehicle meets the following
conditions:
^ The vehicle is not in a Reduced Engine Power mode.
^ The ignition is ON.
^ The engine is OFF.
5. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 6.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
7. Inspect the carpet fit under the accelerator pedal. 8. Install the left IP lower closeout insulator
panel.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions
Air Flow Meter/Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6605
Electrical Symbols Part 1
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6606
Electrical Symbols Part 2
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6607
Electrical Symbols Part 3
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6608
Electrical Symbols Part 4
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6609
Air Flow Meter/Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6610
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6611
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6612
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6613
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6614
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6615
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6616
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6617
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6618
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6619
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6620
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6621
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6622
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6623
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6624
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6625
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6626
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6627
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6628
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6629
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6630
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6631
Equivalents - Decimal And Metric Part 1
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6632
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6633
Various symbols are used in order to describe different service operations.
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6634
Conversion - English/Metric
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Delivery and Air Induction > Air Flow Meter/Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6635
Intake Air Temperature (IAT)/Mass Air Flow (MAF) Sensor
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Air Flow Meter/Sensor: Service and Repair
MASS AIR FLOW (MAF)/INTAKE AIR TEMPERATURE (IAT) SENSOR REPLACEMENT
REMOVAL PROCEDURE
IMPORTANT: Take care when handling the mass air flow/intake air temperature (MAF/IAT) sensor.
Do not dent, puncture, or otherwise damage the honeycell located at the air inlet end of the
MAF/IAT. Do not touch the sensing elements or allow anything including cleaning solvents and
lubricants to come in contact with them. Use a small amount of a non-silicone based lubricant, on
the air duct only, to aid in installation. Do not drop or roughly handle the MAF/IAT sensor.
1. Remove air intake resonator. 2. Disconnect the MAF/IAT sensor electrical connector. 3. Loosen
the clamp securing the MAF/IAT sensor to the air cleaner housing. 4. Remove the MAF/IAT sensor
from the air cleaner assembly.
INSTALLATION PROCEDURE
IMPORTANT: The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction.
The arrow must point toward the engine.
1. Locate the air flow direction arrow (2) on the MAF/IAT sensor.
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2. Install the MAF/IAT sensor on to the air cleaner housing. 3. Tighten the clamp securing the
MAF/IAT sensor to the air cleaner housing. 4. Connect the MAF/IAT electrical connector. 5. Install
air intake resonator.
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Delivery and Air Induction > Flexible Fuel Sensor > Component Information > Diagrams
Fuel Composition Sensor - W/L59 Only
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Delivery and Air Induction > Flexible Fuel Sensor > Component Information > Diagrams > Page 6641
Flexible Fuel Sensor: Description and Operation
FUEL COMPOSITION SENSOR DESCRIPTION
The Fuel Composition Sensor (FCS), or flex fuel sensor (service parts term), measures the
ethanol-gasoline ratio of the fuel being used in a flexible fuel vehicle. Flexible fuel vehicles can be
operated with a blend of ethanol and gasoline, up to 85 percent ethanol. In order to adjust the
ignition timing and the fuel quantity to be injected, the engine management system requires
information about the percentage of ethanol in the fuel.
The FCS uses quick-connect style fuel connections, an incoming fuel connection, and an outgoing
fuel connection. The two connections have different diameters, to prevent incorrect attachment of
the fuel lines. All fuel passes through the fuel composition sensor before continuing on to the fuel
rail. The fuel composition sensor measures two different fuel related parameters, and sends an
electrical signal to the Powertrain Control Module (PCM) to indicate ethanol percentage, and fuel
temperature.
The fuel composition sensor has a three-wire electrical harness connector. The three wires provide
a ground circuit, a power source, and a signal output to the PCM. The power source is vehicle
system voltage, +12 volts), and the ground circuit connects to chassis ground. The signal circuit
carries both the ethanol percentage and fuel temperature within the same signal, on the same wire.
The FCS uses a microprocessor inside the sensor to measure the ethanol percentage and fuel
temp, and change an output signal accordingly. The electrical characteristic of the FCS signal is a
square-wave digital signal. The signal is both variable frequency and variable pulse width. The
frequency of the signal indicates the ethanol percentage, and the pulse width indicates the fuel
temperature. The PCM provides an internal pull-up to five volts on the signal circuit, and the FCS
pulls the 5 volts to ground in pulses. The output frequency is linear to the percentage of ethanol
content in the fuel. The normal range of operating frequency is between 50 and 150 Hertz, with 50
Hertz representing 0 percent ethanol, and 150 Hertz representing 100 percent ethanol. The normal
pulse width range of the digital pulses is between 1 and 5 milliseconds, with 1 millisecond
representing 40°C (-40°F), and 5 milliseconds representing 125°C (257°F).
The microprocessor inside the sensor is capable of a certain amount of self-diagnosis. An output
frequency of 170 Hertz indicates either that the fuel is contaminated or contains methanol (it should
not), or that an internal sensor electrical fault has been detected. Certain substances dissolved in
the fuel can cause the fuel to be contaminated, raising the output frequency to be higher than the
actual ethanol percentage should indicate. Examples of these substances include water, sodium
chloride (salt), and methanol.
It should be noted that it is likely that the FCS will indicate a slightly lower ethanol percentage than
what is advertised at the fueling station. This is not a fault of the sensor. The reason has to do with
government requirements for alcohol-based motor fuels. Government regulations require that
alcohol intended for use as motor fuel be DENATURED. This means that 100 percent pure ethanol
is first denatured with approximately 4% percent gasoline, before being mixed with anything else.
When an ethanol gasoline mixture is advertised as E85, the 85 percent ethanol was denatured
before being blended with gasoline, meaning an advertised E85 fuel contains only about 81
percent ethanol. The FCS measures the actual percentage of ethanol in the fuel.
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Delivery and Air Induction > Flexible Fuel Sensor > Component Information > Diagrams > Page 6642
Flexible Fuel Sensor: Service and Repair
FUEL COMPOSITION SENSOR REPLACEMENT
REMOVAL PROCEDURE
1. Turn OFF the ignition. 2. Relieve the fuel pressure. Refer to Fuel Pressure Relief Procedure. 3.
Raise the vehicle. 4. Remove the fuel composition sensor fuel composition sensor (FCS)
attachment nuts (1).
5. Disconnect the FCS inlet and outlet pipes from the FCS.
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6. Disconnect the FCS electrical connector (1). 7. Remove the FCS and bracket assembly from the
frame rail.
8. Remove the FCS bolts and remove from the bracket.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the FCS to the bracket and install bolts.
Tighten Tighten bolts to 10 N.m (89 lb in).
2. Install FCS and bracket assembly to frame.
3. Install FCS bracket to frame nuts.
Tighten Tighten nuts (1) to 17 N.m (13 lb ft).
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4. Connect the FCS inlet and outlet pipes to the FCS.
5. Connect the FCS electrical connector (1). 6. Lower the vehicle. 7. Start the engine and check for
fuel leaks.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Locations
Locations View
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Instructions
Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Instructions > Page 6651
Electrical Symbols Part 1
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Instructions > Page 6652
Electrical Symbols Part 2
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Instructions > Page 6653
Electrical Symbols Part 3
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Instructions > Page 6654
Electrical Symbols Part 4
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Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Instructions > Page 6658
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6659
inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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Instructions > Page 6660
- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6661
NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Instructions > Page 6662
Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6663
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6664
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6665
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6666
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6667
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6668
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6669
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Instructions > Page 6670
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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Instructions > Page 6671
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6672
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6673
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6674
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6675
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6676
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6677
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6678
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6679
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6680
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Diagram Information and
Instructions > Page 6681
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Page 6682
Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Page 6683
4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Sensors and Switches - Fuel
Delivery and Air Induction > Throttle Position Sensor > Component Information > Diagrams > Page 6684
4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Technical Service Bulletins > Customer Interest for Throttle Body: > 04-06-04-040 > Jun > 04 > Fuel System Low/Rough or Unstable Idle
Throttle Body: Customer Interest Fuel System - Low/Rough or Unstable Idle
Bulletin No.: 04-06-04-040
Date: June 14, 2004
TECHNICAL
Subject: Idle Instability, Low or Rough Idle with Electronic Throttle Control (Clean Throttle Body)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC Sierra, Yukon, Yukon XL with 4.8L, 5.3L
or 6.0L V8 Engine (VINs V, T, Z, N, U - RPOs LR4, LM7, L59, LQ9, LQ4) and Electronic Throttle
Control
Condition
Some owners may comment on an idle instability, low idle speed or rough idle.
Cause
Condition may be caused by deposits in the throttle body bore.
Correction
Clean throttle body bore and throttle valve plate of carbon using a shop rag and an appropriate
cleaner. Refer to Engine Controls Repair Procedures - Throttle Body Cleaning Procedure. This
procedure may be performed at any mileage necessary. Check to determine if the PCM calibration
has been previously updated to one that includes the update for throttle body coking. For 2003
model year vehicles, look in the operating system portion of the calibration. For 2000-2002 model
year vehicles, look in the engine portion of the calibration. If not, then update the PCM calibration to
the latest calibration.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Throttle Body: > 04-06-04-040 > Jun > 04 >
Fuel System - Low/Rough or Unstable Idle
Throttle Body: All Technical Service Bulletins Fuel System - Low/Rough or Unstable Idle
Bulletin No.: 04-06-04-040
Date: June 14, 2004
TECHNICAL
Subject: Idle Instability, Low or Rough Idle with Electronic Throttle Control (Clean Throttle Body)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC Sierra, Yukon, Yukon XL with 4.8L, 5.3L
or 6.0L V8 Engine (VINs V, T, Z, N, U - RPOs LR4, LM7, L59, LQ9, LQ4) and Electronic Throttle
Control
Condition
Some owners may comment on an idle instability, low idle speed or rough idle.
Cause
Condition may be caused by deposits in the throttle body bore.
Correction
Clean throttle body bore and throttle valve plate of carbon using a shop rag and an appropriate
cleaner. Refer to Engine Controls Repair Procedures - Throttle Body Cleaning Procedure. This
procedure may be performed at any mileage necessary. Check to determine if the PCM calibration
has been previously updated to one that includes the update for throttle body coking. For 2003
model year vehicles, look in the operating system portion of the calibration. For 2000-2002 model
year vehicles, look in the engine portion of the calibration. If not, then update the PCM calibration to
the latest calibration.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Technical Service Bulletins > Page 6698
Throttle Body: Specifications
Throttle Body Nuts ...............................................................................................................................
................................................. 10 Nm (89 inch lbs.) Throttle Body Studs ..........................................
..................................................................................................................................... 6 Nm (53 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Technical Service Bulletins > Page 6699
Throttle Body: Description and Operation
Throttle Body Assembly
The throttle body for the TAC system is similar to a conventional throttle body with a couple of
exceptions. One exception being the use of a motor to control the TP instead of a mechanical
cable. The other exception is the new design TP sensor. The TP sensor mounts on the side of the
throttle body opposite the throttle actuator motor. The TP sensor is actually 2 individual TP sensors
within one housing. Separate signal, low reference, and 5-volt reference circuits are used to
connect the TP sensors and the TAC module. The TP sensor 1 signal voltage increases as the
throttle opens, from around 1.0 volt at 0 throttle to above 3.5 volts at 100 percent throttle. TP
sensor 2 signal voltage decreases as the throttle is opened, from around 3.8 volts at 0 throttle to
below 1.0 volt at 100 percent throttle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC)
Throttle Body: Service and Repair Throttle Body Assembly Replacement (W/O ETC)
REMOVAL PROCEDURE
1. Remove the air intake duct.
2. Disconnect the accelerator control cable and the cruise control cable from the throttle body. 3.
Disconnect the vacuum hose from the throttle body.
4. Disconnect the throttle position (TP) sensor and idle air control (IAC) valve harness connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6702
5. Disconnect the coolant hose from the throttle body.
6. Disconnect the coolant hose from the vapor vent pipe.
7. Remove the throttle body attaching nuts. 8. Remove the throttle body and the gasket. Discard
the gasket.
NOTE: In order to prevent damage to the sealing surfaces, carefully use sharp tools in cleaning the
old gasket from the aluminum surfaces.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6703
IMPORTANT: DO NOT soak the throttle body in a cold immersion type cleaner. The throttle plate has a factory
applied sealing compound. DAG material is applied to the outside edge of the plate and the throttle
bore to prevent air bypass at closed throttle. Strong solvents or brushing removes the material. To
clean the throttle body following disassembly, use a spray type cleaner such as GM X-66A or GM
P/N 1052626. Use a shop towel to remove heavy deposits.
- The TP sensor and the IAC valve are electrical components, and should NOT come in contact
with solvent or cleaner in order to avoid damage.
9. Clean the gasket sealing surfaces.
INSTALLATION PROCEDURE
1. Install the throttle body with a new gasket.
NOTE: Refer to the Fastener Notice in Service Precautions.
2. Install the throttle body attaching nuts.
Tighten Tighten the nuts to 10 N.m (89 lb in).
3. Connect the coolant hose to the throttle body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6704
4. Connect the coolant hose to the vapor vent pipe.
5. Connect the accelerator control cable and the cruise control cable to the throttle body.
6. Connect the TP sensor and the IAC valve electrical connectors. 7. Connect the vacuum hose to
the throttle body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6705
8. Install the air intake duct. 9. With the engine OFF, verify that the accelerator pedal moves freely.
Depress the accelerator pedal to the floor and release the pedal.
10. In order to reset the IAC valve, perform the following procedure:
10.1. Turn ON the ignition for 10 seconds. 10.2. Turn OFF the ignition for 5 seconds. 10.3. Start the
engine and check for the proper idle speed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6706
Throttle Body: Service and Repair Throttle Body Assembly Replacement (W/ ETC)
REMOVAL PROCEDURE
NOTE: Handle the electronic throttle control components carefully. Use cleanliness in order to
prevent damage. Do not drop the electronic throttle control components. Do not roughly handle the
electronic throttle control components. Do not immerse the electronic throttle control components in
cleaning solvents of any type.
IMPORTANT: An eight digit part identification number is stamped on the throttle body casting.
Refer to this number if servicing, or part replacement is required.
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle. 2. Partially drain the cooling system
in order to allow the hoses at the throttle body to be removed. Refer to Draining and Filling Cooling
System in
Cooling System.
3. Lower the vehicle.
IMPORTANT: Cover or plug any openings when servicing the throttle body in order to prevent
possible contamination.
4. Remove the air intake duct.
5. Disconnect the throttle actuator motor harness connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6707
6. Disconnect the throttle position (TP) and intake air control (IAC) sensor harness connector. 7.
Disconnect the crankcase ventilation hose from the throttle body.
8. Remove the throttle body attaching bolts. 9. Disconnect the coolant hoses from the throttle body.
10. Remove the throttle body and the gasket.
IMPORTANT: Do not reuse the throttle body gasket. Install a new gasket during assembly.
11. Discard the throttle body gasket. 12. Inspect the crankcase ventilation hose and the tube.
Replace any damaged components.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6708
1. Install a new throttle body gasket. 2. Connect the coolant hoses to the throttle body. 3. Install the
throttle body assembly.
NOTE: Refer to Fastener Notice in Service Precautions.
IMPORTANT: Always use a torque wrench in order to obtain the proper torque.
4. Install the throttle body attaching bolts.
Tighten Tighten the throttle body bolts to 10 N.m (89 lb in).
5. Connect the TP and IAC sensor harness connector. 6. Connect the crankcase ventilation hose
to the throttle body.
IMPORTANT: Verify that the throttle actuator motor harness connector and the connector seal are
properly installed and not damaged.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6709
7. Connect the throttle actuator motor harness connector.
8. Install the air intake duct. 9. Connect the intake air temperature sensor harness connector.
10. Refill the cooling system. Refer to Draining and Filling Cooling System in Cooling System. 11.
Verify that the vehicle meets the following conditions:
- The vehicle is not in a Reduced Engine Power mode.
- The ignition is ON.
- The engine is OFF.
12. Connect a scan tool in order to test for a proper throttle-opening and throttle-closing range. 13.
Operate the accelerator pedal and monitor the throttle angles. The accelerator pedal should
operate freely, without binding, between a closed
throttle, and a wide open throttle (WOT).
14. Start the engine. 15. Inspect for coolant leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Body > Component
Information > Service and Repair > Throttle Body Assembly Replacement (W/O ETC) > Page 6710
Throttle Body: Service and Repair Throttle Body Cleaning Procedure
IMPORTANT: Over extended time and mileage, deposits may accumulate on the back of the
throttle valve plate. The source of the deposit is exhaust gas recirculation (EGR) gas. Typically
these deposits pose no problem. Occasionally the deposit may accumulate to a point where
perceived pedal effort or throttle valve movement is effected. This procedure should not be
performed on vehicles with mileage under 80450 km (50,000 mi).
1. Remove the air intake duct.
CAUTION: Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected
movement of the throttle blade could cause personal injury.
NOTE: Do not insert any tools into the throttle body bore in order to avoid damage to the throttle
valve plate.
2. Inspect the throttle body bore and the throttle valve plate for deposits. You will need to open the
throttle valve in order to inspect all surfaces.
NOTE: Do not use any solvent that contains Methyl Ethyl ketone (MEK). This solvent may damage
fuel system components.
3. Clean the throttle body bore and the throttle valve plate using a clean shop towel with GM Top
Engine Cleaner, P/N 1052626 or AC-Delco
Carburetor Tune-Up Conditioner, P/N X66-P, or an equivalent product.
4. Install the air intake duct.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Cable/Linkage >
Component Information > Service and Repair
Throttle Cable/Linkage: Service and Repair
ACCELERATOR CONTROLS CABLE REPLACEMENT
REMOVAL PROCEDURE
1. Remove the engine sight shield.
2. Disconnect the accelerator cable from the throttle body lever.
3. Remove the accelerator cable from the cable bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Cable/Linkage >
Component Information > Service and Repair > Page 6714
4. Unclip the accelerator cable from the engine sight shield mounting bracket.
5. Remove the left instrument panel (IP) insulator. 6. Disconnect the accelerator cable retainer (3)
from the accelerator pedal lever (2). 7. Squeeze the accelerator cable cover tangs (1) and push the
cable through the dash panel. 8. Remove the accelerator cable.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Cable/Linkage >
Component Information > Service and Repair > Page 6715
1. Install the accelerator cable through the dash panel. Snap the accelerator cable cover tangs (1)
through the dash panel. 2. Install the accelerator cable through the slot in the accelerator pedal
lever (2). 3. Seat the retainer (3) in the accelerator pedal lever (2).
4. Connect the accelerator cable to the throttle body lever.
5. Slide the accelerator cable into the slot on the accelerator cable bracket. Snap the locking tab
into position.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Cable/Linkage >
Component Information > Service and Repair > Page 6716
6. Clip the accelerator cable into the engine sight shield mounting bracket.
7. Test for complete throttle opening and closing range by operating the accelerator pedal. Also
inspect the carpet fit under the accelerator pedal. The
throttle should operate freely without binding between full closed throttle and wide open throttle
(WOT).
8. Install the left IP insulator. 9. Install the engine sight shield.
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Component Information > Locations
Locations View
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Throttle Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Component Information > Diagrams > Diagram Information and Instructions > Page 6724
Electrical Symbols Part 3
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Component Information > Diagrams > Diagram Information and Instructions > Page 6725
Electrical Symbols Part 4
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Throttle Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6736
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6738
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 6739
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6740
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 6746
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6750
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Fuel Delivery and Air Induction > Throttle Position Sensor >
Component Information > Diagrams > Diagram Information and Instructions > Page 6751
Conversion - English/Metric
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Component Information > Diagrams > Diagram Information and Instructions > Page 6752
Throttle Position Sensor: Connector Views
Throttle Position (TP) Sensor
Throttle Position (TP) Sensor (Dual Track)
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Throttle Position Sensor: Service and Repair
REMOVAL PROCEDURE
CAUTION: Refer to the Battery Disconnect Caution in Service Precautions.
NOTE: The TP sensor is an electrical component. Do not soak the TP sensor in any liquid cleaner
or solvent as damage may result.
IMPORTANT: If the vehicle is equipped with electronic throttle control (ETC) the throttle position
(TP) sensor is NOT serviceable. The throttle body and TP sensor MUST be serviced as a complete
assembly.
1. Disconnect the negative battery cable. 2. Remove the generator.
3. Disconnect the throttle position TP sensor electrical connector.
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4. Remove the TP sensor attaching screws (5). 5. Remove the TP sensor (6). 6. Remove the TP
sensor O-ring seal (7).
INSTALLATION PROCEDURE
1. Install the TP sensor O-ring seal (7) on the TP sensor (6). 2. Install the TP sensor on the throttle
body with the throttle valve in the closed position. Verify the TP sensor lever lines up with the TP
sensor drive
lever on the throttle shaft.
NOTE: Refer to the Fastener Notice in Service Precautions.
3. Install the TP sensor attaching screws (5).
Tighten Tighten the screws to 2 N.m (18 lb in).
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4. Connect the TP sensor electrical connector.
5. Install the generator. 6. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions
Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Information > Diagrams > Diagram Information and Instructions > Page 6762
Electrical Symbols Part 1
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Information > Diagrams > Diagram Information and Instructions > Page 6763
Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Information > Diagrams > Diagram Information and Instructions > Page 6776
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6777
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6778
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6779
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6780
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6781
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6782
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6783
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6784
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6785
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6786
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6787
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information > Diagrams > Diagram Information and Instructions > Page 6788
Equivalents - Decimal And Metric Part 1
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Information > Diagrams > Diagram Information and Instructions > Page 6789
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Information > Diagrams > Diagram Information and Instructions > Page 6790
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6791
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6792
Camshaft Position (CMP) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Camshaft Position Sensor > Component
Information > Diagrams > Page 6793
Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Information > Diagrams > Page 6794
Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Locations
Locations View
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions
Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6800
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6801
Electrical Symbols Part 2
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6802
Electrical Symbols Part 3
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6803
Electrical Symbols Part 4
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6804
Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6815
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6816
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6817
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6818
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6819
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6820
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6821
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6822
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6823
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6824
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Information > Diagrams > Diagram Information and Instructions > Page 6826
Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6828
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6829
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Diagram Information and Instructions > Page 6830
Crankshaft Position (CKP) Sensor
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Diagrams > Page 6831
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Service and Repair > CKP System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Service and Repair > CKP System Variation Learn Procedure > Page 6834
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
Information > Service and Repair > CKP System Variation Learn Procedure > Page 6835
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Crankshaft Position Sensor > Component
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3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Cable > Component Information >
Specifications
Ignition System Specifications
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Cable > Component Information >
Service and Repair > Spark Plug Wire Inspection
Ignition Cable: Service and Repair Spark Plug Wire Inspection
Spark plug wire integrity is vital for proper engine operation. A thorough inspection will be
necessary to accurately identify conditions that may affect engine operation. Inspect for the
following conditions:
^ Correct routing of the spark plug wires-Incorrect routing may cause cross-firing.
^ Any signs of cracks or splits in the wires.
^ Inspect each boot for the following conditions: Tearing
- Piercing
- Arcing
- Carbon tracking
- Corroded terminal
If corrosion, carbon tracking or arcing are indicated on a spark plug wire boot or on a terminal,
replace the wire and the component connected to the wire.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Cable > Component Information >
Service and Repair > Spark Plug Wire Inspection > Page 6842
Ignition Cable: Service and Repair Spark Plug Wire Replacement
REMOVAL PROCEDURE
1. Disconnect the spark plug wire at each spark plug.
^ Twist each spark plug 1/2 turn.
^ Pull only on the boot in order to remove the wire from each spark plug.
2. Disconnect the spark plug wire from the ignition coil.
^ Twist each spark plug boot 1/2 turn.
^ Pull only on the boot in order to remove the wires from the ignition coil.
SPARK PLUG WIRE LENGTH V8
Spark Plug Wire Length V8
^ The Melco(R), square design, uses a spark plug wire (1) that is 145 mm (5.70 in) length cable
seal to cable seal.
^ The Delphi(R), round design uses a spark plug wire (2) that is 110 mm (4.30 in) length cable seal
to cable seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Cable > Component Information >
Service and Repair > Spark Plug Wire Inspection > Page 6843
Ignition Coils
^ There are 2 different manufacturers for the ignition coils, the Melco(R) (1) square design, and the
Delphi(R) (2) round design. These 2 coils use 2 different spark plug wire, and mounting brackets.
^ Melco(R), square design, coil mounting bracket (1).
^ Delphi(R), round design, coil mounting bracket (2).
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Cable > Component Information >
Service and Repair > Spark Plug Wire Inspection > Page 6844
1. Install the spark plug wires at the ignition coil. 2. Install the spark plug wire to each spark plug. 3.
Inspect the wires for proper installation:
^ Push sideways on each boot in order to inspect the seating.
^ Reinstall any loose boot.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams
Ignition Coil: Diagrams
Ignition Coil/Driver - Cylinder 1
Ignition Coil/Driver - Cylinder 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6848
Ignition Coil/Driver - Cylinder 3
Ignition Coil/Driver - Cylinder 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6849
Ignition Coil/Driver - Cylinder 5
Ignition Coil/Driver - Cylinder 6
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6850
Ignition Coil/Driver - Cylinder 7
Ignition Coil/Driver - Cylinder 8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6851
Ignition Coil: Description and Operation
IGNITION COILS
Ignition Coils
The following are the 2 different manufacturers for the ignition coils. ^
Melco (1), square design
^ Delphi (2), round design
These 2 coils use 2 different spark plug wire lengths, and mounting brackets.
Each ignition coil has an ignition 1 feed and a ground. The PCM supplies a low reference and an
Ignition Control (IC) circuit. Each ignition coil contains a solid state driver module as the primary
element. The PCM signals the coil driver to initiate a firing event by applying the IC circuit voltage
for the appropriate time, or dwell. When the voltage is removed the coil fires the spark plug. The
coils are current limited to prevent overloading if the IC current is held high too long.
IGNITION COIL MOUNTING BRACKETS
Ignition Coil Mounting Brackets
The following are the 2 different types of mounting brackets. ^
Melco (1), square design
^ Delphi (2), round design
The ignition coil mounting brackets must match the appropriate coil type.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6852
Spark Plug Wire Length V8
The following are the 2 different lengths of spark plug wire. ^
Melco (1), square design-Uses a spark plug wire that is 145 mm length cable seal to cable seal.
^ Delphi (2), round design-Uses a spark plug wire that is 110 mm length cable seal to cable seal.
The ignition coil wires must match the appropriate coil type.
The spark plugs are connected to their respective coils by a short secondary wire. The plugs are
tipped with platinum for long wear and higher efficiency.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6853
Ignition Coil: Service and Repair
REMOVAL PROCEDURE
1. Disconnect the spark plug wires at the ignition coils.
2. Disconnect the ignition coil harness connector.
3. Remove the ignition coil mounting bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6854
4. Remove the ignition coil.
INSTALLATION PROCEDURE
1. Install the ignition coil to the bracket.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ignition coil mounting bolts.
Tighten Tighten the ignition coil mounting bolts to 8 N.m (71 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Coil > Component Information >
Diagrams > Page 6855
3. Connect the ignition coil harness connector.
4. Connect the spark plug wires at the ignition coils.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Relay > Component Information >
Locations
Ignition Relay: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Relay > Component Information >
Locations > Page 6859
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Relay > Component Information >
Locations > Page 6860
Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTION
The ignition relay supplies battery positive voltage to the following components: ^
The fuel injectors
^ The ignition coils
^ The powertrain control module (PCM)
^ The throttle actuator control (TAC) module
DIAGNOSTIC AIDS
The following will occur if the ignition relay fails to close: ^
The engine cranks, but does not run.
^ Scan tool data will be available.
^ Instrument panel lights will illuminate.
TEST DESCRIPTION
Steps 1-5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Ignition Relay > Component Information >
Locations > Page 6861
Steps 6-11
The numbers below refer to the step numbers on the diagnostic table. 2. This step is testing the
battery positive voltage circuit of the ignition relay. 3. This step is testing the ignition 1 positive
voltage circuit of the ignition relay. 4. This step is testing the coil ground circuit of the ignition relay.
5. This step isolates the circuits from the ignition relay. All of the circuits at the relay are good if the
test lamp illuminates.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark
Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark
Knock/MIL ON/ DTC P0332 Set > Page 6870
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > Customer Interest for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine Controls - Spark
Knock/MIL ON/ DTC P0332 Set > Page 6871
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 6877
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: > 02-06-04-023A > Jun > 02 > Engine
Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 6878
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Technical Service Bulletins > Page 6879
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6882
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6883
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6884
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6885
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6886
Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6887
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6888
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6889
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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Diagrams > Diagram Information and Instructions > Page 6903
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Diagrams > Diagram Information and Instructions > Page 6904
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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Diagrams > Diagram Information and Instructions > Page 6905
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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Diagrams > Diagram Information and Instructions > Page 6906
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Diagrams > Diagram Information and Instructions > Page 6908
Equivalents - Decimal And Metric Part 1
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Diagrams > Diagram Information and Instructions > Page 6909
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Diagrams > Diagram Information and Instructions > Page 6910
Various symbols are used in order to describe different service operations.
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Diagrams > Diagram Information and Instructions > Page 6911
Conversion - English/Metric
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Diagram Information and Instructions > Page 6912
Knock Sensor (KS)
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Knock Sensor > Component Information >
Diagrams > Page 6913
Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
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Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
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1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Relays and Modules - Ignition System >
Ignition Relay > Component Information > Locations
Ignition Relay: Locations
Locations View
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Ignition Relay > Component Information > Locations > Page 6920
Fuse Block - Underhood
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Ignition Relay > Component Information > Locations > Page 6921
Ignition Relay: Testing and Inspection
CIRCUIT DESCRIPTION
The ignition relay supplies battery positive voltage to the following components: ^
The fuel injectors
^ The ignition coils
^ The powertrain control module (PCM)
^ The throttle actuator control (TAC) module
DIAGNOSTIC AIDS
The following will occur if the ignition relay fails to close: ^
The engine cranks, but does not run.
^ Scan tool data will be available.
^ Instrument panel lights will illuminate.
TEST DESCRIPTION
Steps 1-5
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Steps 6-11
The numbers below refer to the step numbers on the diagnostic table. 2. This step is testing the
battery positive voltage circuit of the ignition relay. 3. This step is testing the ignition 1 positive
voltage circuit of the ignition relay. 4. This step is testing the coil ground circuit of the ignition relay.
5. This step isolates the circuits from the ignition relay. All of the circuits at the relay are good if the
test lamp illuminates.
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Camshaft Position Sensor > Component Information > Locations
Locations View
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Camshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions
Camshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
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Electrical Symbols Part 1
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Camshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6930
Electrical Symbols Part 2
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Camshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6931
Electrical Symbols Part 3
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Camshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6932
Electrical Symbols Part 4
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Camshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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Camshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6945
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Conversion - English/Metric
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Camshaft Position (CMP) Sensor
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Camshaft Position Sensor: Description and Operation
The CMP sensor is also a magneto resistive sensor, with the same type of circuits as the CKP
sensor. The CMP sensor signal is a digital ON/OFF pulse, output once per revolution of the
camshaft. The CMP sensor information is used by the PCM to determine the position of the valve
train relative to the CKP.
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Camshaft Position Sensor: Service and Repair
REMOVAL PROCEDURE
IMPORTANT: Clean the area around the camshaft position (CMP) sensor before removal in order
to prevent debris from entering the engine.
Camshaft Position Sensor (CMP)
1. Remove the engine sight shield, as necessary. 2. Disconnect the CMP sensor electrical
connector. 3. Remove the CMP sensor bolt. 4. Remove the CMP sensor.
INSTALLATION PROCEDURE
Camshaft Position Sensor (CMP)
1. Install the CMP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CMP sensor bolt.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
3. Connect the CMP sensor electrical connector. 4. Install the engine sight shield, as necessary.
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Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Locations
Locations View
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Crankshaft Position Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Crankshaft Position Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6987
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6988
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6989
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6990
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6991
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6992
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6993
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6994
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6995
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6996
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 6997
Crankshaft Position (CKP) Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Diagrams > Page 6998
Crankshaft Position Sensor: Description and Operation
The Crankshaft Position (CKP) sensor is a three wire sensor based on the magneto resistive
principle. A magneto resistive sensor uses two magnetic pickups between a permanent magnet. As
an element such as a reluctor wheel passes the magnets the resulting change in the magnetic field
is used by the sensor electronics to produce a digital output pulse. The PCM supplies a 12-volt, low
reference, and signal circuit to the CKP sensor. The sensor returns a digital ON/OFF pulse 24
times per crankshaft revolution. The CKP sensor reads the crankshaft mounted reluctor wheel to
identify pairs of cylinders at Top Dead Center (TDC).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Service and Repair > CKP System Variation Learn Procedure
Crankshaft Position Sensor: Service and Repair CKP System Variation Learn Procedure
IMPORTANT: For additional diagnostic information, refer to DTC P1336.
1. Install a scan tool. 2. With a scan tool, monitor the powertrain control module (PCM) for DTCs. If
other DTCs are set, except DTC P1336, refer to Diagnostic Trouble
Code (DTC) List for the applicable DTC that set.
3. With a scan tool, select the crankshaft position (CKP) variation learn procedure. 4. Observe the
fuel cut-off for the engine that you are performing the learn procedure on. 5. The scan tool instructs
you to perform the following:
^ Block the drive wheels.
^ Apply the vehicles parking brake.
^ Cycle the ignition from OFF to ON.
^ Apply and hold the brake pedal.
^ Start and idle the engine.
^ Turn OFF the AC.
^ Place the vehicle's transmission in Park (A/T) or Neutral (M/T).
^ The scan tool monitors certain component signals to determine if all the conditions are met to
continue with the procedure. The scan tool only displays the condition that inhibits the procedure.
The scan tool monitors the following components: - CKP sensors activity-If there is a CKP sensor
condition, refer to the applicable DTC that set. - Camshaft position (CMP) sensor activity-If there is
a CMP sensor condition, refer to the applicable DTC that set. - Engine coolant temperature
(ECT)-If the ECT is not warm enough, idle the engine until the engine coolant temperature reaches
the correct
temperature.
6. With the scan tool, enable the CKP system variation learn procedure.
IMPORTANT: While the learn procedure is in progress, release the throttle immediately when the
engine starts to decelerate. The engine control is returned to the operator and the engine responds
to throttle position after the learn procedure is complete.
7. Slowly increase the engine speed to the RPM that you observed. 8. Immediately release the
throttle when fuel cut-off is reached. 9. The scan tool displays Learn Status: Learned this ignition. If
the scan tool does NOT display this message and no additional DTCs set, refer to
Symptoms - Engine Mechanical. If a DTC set, refer to Diagnostic Trouble Code (DTC) List for the
applicable DTC that set.
10. Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Service and Repair > CKP System Variation Learn Procedure >
Page 7001
Crankshaft Position Sensor: Service and Repair Crankshaft Position (CKP) Sensor Replacement
REMOVAL PROCEDURE
IMPORTANT: Perform the CKP System Variation Learn Procedure when the crankshaft position
sensor is removed or replaced.
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise the vehicle. Refer to Lifting and Jacking the
Vehicle. 3. Remove the starter.
4. Disconnect the crankshaft position (CKP) sensor electrical connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Service and Repair > CKP System Variation Learn Procedure >
Page 7002
5. Clean the area around the CKP sensor before removal in order to avoid debris from entering the
engine. 6. Remove the CKP sensor retaining bolt. 7. Remove the CKP sensor.
INSTALLATION PROCEDURE
Crankshaft Position Sensor (CKP)
1. Install the CKP sensor.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the CKP sensor retaining fastener.
Tighten Tighten the bolt to 25 N.m (18 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Crankshaft Position Sensor > Component Information > Service and Repair > CKP System Variation Learn Procedure >
Page 7003
3. Connect the CKP sensor electrical connector.
4. Install the starter. 5. Lower the vehicle. 6. Connect the negative battery cable. 7. Perform the
CKP system variation learn procedure. See: Testing and Inspection/Programming and Relearning
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Ignition Switch > Ignition Switch Lock Cylinder > Component Information > Technical Service Bulletins > Ignition Lock
Cylinder - Revised Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: Customer Interest Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 7017
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > Customer Interest for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 7018
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set
Knock Sensor: All Technical Service Bulletins Engine Controls - Spark Knock/MIL ON/ DTC P0332
Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 02-06-04-023A
Date: June, 2002
TECHNICAL
Subject: Audible Spark Knock (Detonation), MIL Illuminated, DTC P0332 Set (Replace Rear Bank
Knock Sensor and RTV Area Around Sensor)
Models: 1998-2002 Chevrolet Camaro, Corvette 1998-2002 Pontiac Firebird with 5.7L Engine (VIN
G - RPO LS1) 1999-2002 Chevrolet Silverado, Suburban, Tahoe 2002 Chevrolet Avalance
1999-2002 GMC Sierra, Yukon, Yukon XL 2002 Cadillac Escalade, Escalade EXT with 4.8L, 5.3L
or 6.0L Engine (VINs V, T, Z, N, U - RPOS LR4, LM7, L59, L09, L04)
This bulletin is being revised to add Cadillac Escalade and Cadillac Escalade EXT to the Models.
Please discard Corporate Bulletin Number 02-06-04-023 (Section 6 - Engine/Propulsion System).
Condition
Some customers may comment on a mild to severe engine ping (commonly referred to as spark
knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the
technician may find DTC P0332 set.
Cause
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion
into the sensor cavity. This condition is more apparent on vehicles in which customers frequently
wash the engine compartment.
Correction
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert
water away from the sensor. Use the procedure and part number listed.
1. Remove the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
2. Remove the wiring harness assembly from the knock sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 7024
3. Remove the rear bank knock sensor.
4. Install the new rear bank knock sensor.
Tighten
Tighten the knock sensor to 20 N.m (15 lb ft).
5. Install the wiring harness assembly to the knock sensor.
6. Apply a bead of RTV silicone sealant approximately 9 mm (3/8 in) wide and 6 mm (1/4 in) high
along the outside edge of the ridge on the engine block valley cover around the rear bank knock
sensor. DO NOT form a complete circle. Leave the rear section open as shown.
7. From the underside of the intake manifold, completely remove the rear intake manifold seal
(foam material).
8. Install the intake manifold. Refer to the Intake Manifold Replacement procedure in the Engine
Controls sub-section of the appropriate Service Manual.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Knock Sensor: >
02-06-04-023A > Jun > 02 > Engine Controls - Spark Knock/MIL ON/ DTC P0332 Set > Page 7025
For vehicles repaired under warranty, use the table as shown
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Technical Service Bulletins > Page 7026
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions
Knock Sensor: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7029
Electrical Symbols Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7030
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7031
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7032
Electrical Symbols Part 4
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Knock Sensor: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7044
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7045
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7046
1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7047
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7048
Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7049
8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7050
12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7051
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7052
1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7053
- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7054
performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7055
Equivalents - Decimal And Metric Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7056
Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7057
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7058
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Diagram Information and Instructions > Page 7059
Knock Sensor (KS)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Page 7060
Knock Sensor: Description and Operation
PURPOSE
The Knock Sensor (KS) system enables the Powertrain Control Module (PCM) to control the
ignition timing advance for the best possible performance while protecting the engine from
potentially damaging levels of detonation. The sensors in the KS system are used by the PCM as
microphones to listen for abnormal engine noise that may indicate pre-ignition/detonation.
SENSOR DESCRIPTION
There are 2 types of KS currently being used: ^
The broadband single wire sensor
^ The flat response 2-wire sensor
Both sensors use piezo-electric crystal technology to produce and send signals to the PCM. The
amplitude and frequency of this signal will vary constantly depending on the vibration level within
the engine. Flat response and broadband KS signals are processed differently by the PCM. The
major differences are outlined below: ^
All broadband sensors use a single wire circuit. Some types of controllers will output a bias voltage
on the KS signal wire. The bias voltage creates a voltage drop the PCM monitors and uses to help
diagnose KS faults. The KS noise signal rides along this bias voltage, and due to the constantly
fluctuating frequency and amplitude of the signal, will always be outside the bias voltage
parameters. Another way to use the KS signals is for the PCM to learn the average normal noise
output from the KS. The PCM uses this noise channel, and KS signal that rides along the noise
channel, in much the same way as the bias voltage type does. Both systems will constantly monitor
the KS system for a signal that is not present or falls within the noise channel.
^ The flat response KS uses a 2-wire circuit. The KS signal rides within a noise channel which is
learned and output by the PCM. This noise channel is based upon the normal noise input from the
KS and is known as background noise. As engine speed and load change, the noise channel upper
and lower parameters will change to accommodate the KS signal, keeping the signal within the
channel. If there is knock, the signal will range outside the noise channel and the PCM will reduce
spark advance until the knock is reduced. These sensors are monitored in much the same way as
the broadband sensors, except that an abnormal signal will stay outside of the noise channel or will
not be present.
KS diagnostics can be calibrated to detect faults with the KS diagnostic inside the PCM, the KS
wiring, the sensor output, or constant knocking from an outside influence such as a loose or
damaged component. In order to determine which cylinders are knocking, the PCM uses KS signal
information when the cylinders are near Top Dead Center (TDC) of the firing stroke.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Page 7061
Knock Sensor: Service and Repair
REMOVAL PROCEDURE
1. Remove the intake manifold. 2. Remove the knock sensor wiring harness assembly.
3. Remove the knock sensor (KS).
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Sensors and Switches - Ignition System >
Knock Sensor > Component Information > Diagrams > Page 7062
1. Install the knock sensor.
Tighten Torque the sensor to 20 N.m (15 lb ft).
2. Install the knock sensor wiring harness assembly. 3. Install the intake manifold.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Technical Service Bulletins > Ignition System - New Spark Plugs & Gapping Info.
Spark Plug: Technical Service Bulletins Ignition System - New Spark Plugs & Gapping Info.
INFORMATION
Bulletin No.: 03-06-04-060B
Date: July 30 2008
Subject: Information on New Spark Plugs and Gapping
Models
Attention:
Please disregard the Set Gap Per Vehicle Specification statement on the side of an ACOelco(R)
Iridium Spark Plug Box. The statement will be removed from the boxes in the future.
Supercede:
This bulletin is being revised to add the Chevrolet SSR and the 2005 Pontiac GTO. Please discard
Corporate Bulletin Number 03-06-04-060A (Section 06 - Engine/Propulsion System).
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the different tip design the gap of the spark
plug has also changed.
^ The new spark plug P/N 12571164 with AC Delco P/N 41-985 is gapped to 1.01 mm (0.040 in)
when the spark plug is made.
Notice:
The spark plug gap is set during manufacturing and should not be changed or damage to the spark
plug may result. Any new spark plug found to not be properly gapped should not be used.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Technical Service Bulletins > Page 7067
Spark Plug: Specifications
This article has been updated with TSB #03-06-04-060B
INFORMATION ON NEW SPARK PLUGS AND GAPPING
SPARK PLUG GAP..............................................................................................................................
.................................................. 1.01 mm (0.040 in.)
^ A new spark plug has been released for use in the above vehicles. The new spark plug has an
Iridium tip instead of the current Platinum tip. Due to the
different tip design, the gap of the spark plug has also changed.
^ The new spark plug, P/N 12571164 with AC Delco P/N 41-985, is gapped to 1.01mm (0.040
inches) when the spark plug is made.
Notice: The spark plug gap is set during manufacturing and should not be changed or damage to
the spark plug may result. Any new spark plug found to not be properly gapped should not be used.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Technical Service Bulletins > Page 7068
Spark Plug: Application and ID
AC Plug Type ......................................................................................................................................
................................................................... 25171803
NGK Plug Type ....................................................................................................................................
................................................................. 12567759
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Service and Repair > Spark Plug Inspection
Spark Plug: Service and Repair Spark Plug Inspection
SPARK PLUG USAGE
^ Verify that the correct spark plug is installed. An incorrect spark plug causes driveability
conditions. Refer to Ignition System Specifications for the correct spark plug.
^ Ensure that the spark plug has the correct heat range. An incorrect heat range causes the
following conditions: Spark plug fouling-Colder plug
- Pre-ignition causing spark plug and/or engine damage-Hotter plug
SPARK PLUG INSPECTION
^ Inspect the terminal P05 (1) for damage. Inspect for a bent or broken terminal post (1).
- Test for a loose terminal post (1) by twisting and pulling the post. The terminal post (1) should
NOT move.
^ Inspect the insulator (2) for flashover or carbon tracking, soot. This is caused by the electrical
charge traveling across the insulator (2) between the terminal post (1) and ground. Inspect for the
following conditions: Inspect the spark plug boot for damage.
- Inspect the spark plug recess area of the cylinder head for moisture, such as oil, coolant, or
water. A spark plug boot that is saturated causes arcing to ground.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Service and Repair > Spark Plug Inspection > Page 7071
^ Inspect the insulator (2) for cracks. All or part of the electrical charge may arc through the crack
instead of the electrodes (3, 4).
^ Inspect for evidence of improper arcing. Measure the gap between the center electrode (4) and the side electrode (3) terminals. Refer to
Ignition System Specifications. An excessively wide electrode gap can prevent correct spark plug
operation.
- Inspect for the correct spark plug torque. Refer to Ignition System Specifications. Insufficient
torque can prevent correct spark plug operation. An over torqued spark plug, causes the insulator
(2) to crack.
- Inspect for signs of tracking that occurred near the insulator tip instead of the center electrode (4).
- Inspect for a broken or worn side electrode (3).
- Inspect for a broken, worn, or loose center electrode (4) by shaking the spark plug. ^
A rattling sound indicates internal damage.
^ A loose center electrode (4) reduces the spark intensity.
- Inspect for bridged electrodes (3, 4). Deposits on the electrodes (3, 4) reduce or eliminates the
gap.
- Inspect for worn or missing platinum pads on the electrodes (3, 4), if equipped.
- Inspect for excessive fouling.
^ Inspect the spark plug recess area of the cylinder head for debris. Dirty or damaged threads can
cause the spark plug not to seat correctly during installation.
SPARK PLUG VISUAL INSPECTION
^ Normal operation-Brown to grayish-tan with small amounts of white powdery deposits are normal
combustion by-products from fuels with additives.
^ Carbon fouled-Dry, fluffy black carbon, or soot caused by the following conditions: Rich fuel mixtures ^
Leaking fuel injectors
^ Excessive fuel pressure
^ Restricted air filter element
^ Incorrect combustion
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Service and Repair > Spark Plug Inspection > Page 7072
- Reduced ignition system voltage output ^
Weak coils
^ Worn ignition wires
^ Incorrect spark plug gap
- Excessive idling or slow speeds under light loads can keep spark plug temperatures so low that
normal combustion deposits may not burn off.
^ Deposit fouling-Oil, coolant, or additives that include substances such as silicone, very white
coating, reduces the spark intensity. Most powdery deposits will not effect spark intensity unless
they form into a glazing over the electrode.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Ignition System > Spark Plug > Component Information >
Service and Repair > Spark Plug Inspection > Page 7073
Spark Plug: Service and Repair Spark Plug Replacement
REMOVAL PROCEDURE
1. Remove the spark plug wires. 2. Loosen each spark plug 1 or 2 turns. 3. Brush or air blast away
any dirt from around the spark plugs. 4. Remove the spark plugs 1 at a time. Place each plug in a
tray marked with the corresponding cylinder numbers.
INSTALLATION PROCEDURE
1. Properly position each spark plug washer. 2. Inspect each spark plug gap. Adjust each plug as
needed.
Specification Spark plug gap: 1.52 mm (0.060 in)
NOTE: Refer to Fastener Notice in Service Precautions.
3. Hand start the spark plugs in the corresponding cylinders. 4. Tighten the spark plugs.
Tighten ^
For used heads tighten the spark plugs to 15 N.m (11 lb ft).
^ For new aluminum heads tighten the spark plugs to 20 N.m (15 lb ft).
^ For new iron heads, tighten the spark plugs to 30 N.m (22 lb ft).
5. Install the spark plug wires.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Specifications
Pressure Regulating Solenoid: Specifications
4L60-E
Pressure Control Solenoid Bracket to Valve Body Bolt .......................................................................
.......................................................................................................... 8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Pressure Control Solenoid Bracket to Valve Body ..............................................................................
...................................................................................................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Diagrams > 4L60-E
Pressure Control Solenoid Valve Connector, Wiring Harness Side
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Diagrams > 4L60-E > Page 7082
Pressure Control Solenoid Valve Connector, Wiring Harness Side
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E
Pressure Regulating Solenoid: Service and Repair 4L60-E
Pressure Regulator Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
filter. 3. Compress the reverse boost valve sleeve into the bore of the oil pump to release tension
on the reverse boost valve retaining ring. 4. Remove the reverse boost valve retaining ring, then
slowly release tension on the reverse boost valve sleeve.
5. Remove the reverse boost valve sleeve (5) and the reverse boost valve (4). 6. Remove the
pressure regulator isolator spring (3) and the pressure regulator valve spring (2). 7. Remove the
pressure regulator valve (1).
Installation Procedure
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7085
1. Install the pressure regulator valve (1). 2. Install the pressure regulator isolator spring (3) and the
pressure regulator valve spring (2). 3. Install the reverse boost valve (4) in the reverse boost valve
sleeve (5). 4. Install the reverse boost valve (4) and sleeve (5) in the oil pump cover.
5. Compress the reverse boost valve sleeve into the bore of the oil pump to expose the retaining
ring slot. 6. Install the reverse boost valve retaining ring, then slowly release tension on the reverse
boost valve sleeve. 7. Install the transmission oil filter and pan. 8. Lower the vehicle. 9. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7086
Pressure Regulating Solenoid: Service and Repair 4L80-E
Pressure Regulator Replacement
^ Tools Required J 36850 Transjel
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the reverse boost valve bushing retainer ring (2).
4. Remove the following from the reverse boost valve cylinder:
^ The reverse boost valve bushing
^ The reverse boost valve
^ The pressure regulator spring retainer
^ The pressure regulator spring
^ The pressure regulator valve
^ The reverse boost valve bushing
Installation Procedure
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7087
1. Install the pressure regulator valve with J 36850. 2. Pre-assemble the following parts:
^ The reverse boost valve bushing
^ A new reverse boost valve
^ A new pressure regulator spring retainer
^ The added isolator pressure regulator spring
^ The pressure regulator spring
3. Install the pre-assembled parts into the pump bore.
4. Install the reverse boost valve bushing retainer ring while holding the reverse boost valve
bushing in place.
Ensure the retainer ring (2) is in the groove.
5. Install the transmission oil pan and the oil filter. 6. Lower the vehicle. 7. Fill the transmission to
the proper level with DEXRON III transmission fluid.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams > Page 7091
Shift Interlock Solenoid: Service and Repair
Automatic Transmission Shift Lock Actuator Replacement
Removal Procedure
Caution: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the body control module bracket. 3. Put the shift lever clevis
into the neutral position. 4. Disconnect the electrical connector. 5. Use a small screwdriver to pry
the automatic transmission shift lock control actuator away from the steering column jacket
assembly and the cable
shift cam assembly.
6. Remove the automatic transmission shift lock control actuator.
Installation Procedure
1. Firmly install the automatic transmission shift lock control actuator onto the steering column
jacket assembly and the cable shift cam assembly. 2. Connect the electrical connector
3. Adjust the automatic transmission shift lock control actuator (with the shift lever clevis in the
neutral position) in the following way:
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams > Page 7092
3.1. Pull out the tab (1) on the adjuster block side (2) of the automatic transmission shift lock
control actuator.
3.2. Press on the adjuster block (2) to compress the internal adjuster spring, which disengages the
adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible.
3.3. Lock the adjuster block (2) in place by pushing in on the tab (1).
4. Inspect the automatic transmission shift lock control actuator for the following items:
4.1. The automatic transmission shift lock control actuator must lock the shift lever clevis when the
shift lever clevis is put into the park position.
4.2. Depress the brake pedal to move the shift lever out of the park position.
4.3. The actuator will be energized.
4.4. Readjust the automatic transmission shift lock control actuator if needed.
5. Install the body control module bracket. 6. Enable the SIR system.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information >
Specifications
Shift Solenoid: Specifications
4L80-E
Solenoid to Valve Body .......................................................................................................................
............................................... 8 Nm (71 inch lbs.)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
4L60-E
Shift Solenoid: Diagrams 4L60-E
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
4L60-E > Page 7098
Shift Solenoid: Diagrams 4L80-E
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 7099
Shift Solenoid: Service and Repair
Control and Shift Solenoids Replacement
Removal Procedure
1. Remove the transmission oil pan and filter.
Important: Do not remove the valve body for the following procedures. Removal of the 1-2
accumulator is necessary only if servicing the pressure control solenoid.
2. Remove the 1-2 accumulator if necessary. 3. Disconnect the internal wiring harness electrical
connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
4. Remove the pressure control solenoid retainer. 5. Remove the pressure control solenoid.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 7100
6. Remove the 1-2 and 2-3 shift solenoid retainers. 7. Remove the 1-2 and 2-3 shift solenoids.
8. Remove the 3-2 control solenoid retainer. 9. Remove the 3-2 control solenoid.
Installation Procedure
1. Install the 3-2 control solenoid. 2. Install the 3-2 control solenoid retainer.
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Page 7101
3. Install the 1-2 and 2-3 shift solenoids. 4. Install the 1-2 and 2-3 shift solenoid retainers.
5. Install the pressure control solenoid. Ensure that the electrical tabs are facing outboard.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
7. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
8. Install the 1-2 accumulator. 9. Install the transmission oil pan and filter.
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Page 7102
10. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Specifications
Torque Converter Clutch Solenoid: Specifications
4L60-E
TCC Solenoid Assembly to Case Bolt
..................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Diagrams > 4L60-E
Torque Converter Clutch Solenoid: Diagrams 4L60-E
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Diagrams > 4L60-E > Page 7108
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E
Torque Converter Clutch Solenoid: Service and Repair 4L60-E
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid, TCC Solenoid, and Wiring
Harness
^ Tools Required J 28458 Seal Protector Retainer Installer
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
the filter. 3. Disconnect the transmission harness 20-way connector from the transmission internal
harness pass-through connector.
Depress both tabs on the connector and pull straight up; do not pry the connector.
Important: Removal of the valve body is not necessary for the following procedure.
4. Remove the 1-2 accumulator assembly. Do not remove the spacer plate.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7111
6. Remove the TCC PWM solenoid retainer. 7. Remove the TCC PWM solenoid in order to access
one of the TCC solenoid retaining bolts.
8. Remove the pressure control solenoid retainer. 9. Remove the pressure control solenoid.
10. Remove the TCC solenoid retaining bolts and the valve body bolts, which retain the internal
wiring harness.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7112
11. Using J28458, release the pass-through electrical connector from the transmission case.
11.1. Use the small end of the J28458 over the top of the connector.
11.2. Twist in order to release the four tabs retaining the connector.
11.3. Pull the harness connector down through the transmission case.
12. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the
transmission case.
13. Inspect the TCC solenoid and wiring harness assembly for the following defects:
^ Damage
^ Cracked connectors
^ Exposed wires
^ Loose pins
Installation Procedure
1. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the
transmission. 2. Install the pass-through electrical connector to the transmission case.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7113
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the valve body bolts, which retain the internal wiring harness and install the TCC solenoid
retaining bolts.
^ Tighten the control valve body retaining bolts to 11 Nm (97 inch lbs.).
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
4. Install the pressure control solenoid.
Ensure that the electrical tabs are facing outboard.
5. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
6. Install the TCC PWM solenoid to the control valve body. 7. Install the TCC PWM solenoid
retainer.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7114
8. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
9. Install the 1-2 accumulator.
10. Connect the transmission harness 20-way connector to the transmission pass-through
connector.
Align the arrows on each half of the connector and insert straight down.
11. Install the transmission oil pan and filter. 12. Lower the vehicle. 13. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7115
Torque Converter Clutch Solenoid: Service and Repair 4L80-E
Torque Converter Clutch (TCC) Valve and Spring Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the oil filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the valve bore plug retainer ring (1).
4. Remove the following parts:
^ The valve bore plug
^ The TCC valve
^ The TCC valve spring
Installation Procedure
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 7116
1. Install the following parts:
^ The TCC valve spring
^ The TCC valve
^ The valve bore plug
2. Install the valve bore plug retainer ring (1). 3. Install the transmission oil pan and oil filter. 4.
Lower the vehicle. 5. Fill the transmission to the proper level with DEXRON III transmission fluid.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Specifications
Transfer Case Actuator: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (14 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (15 ft. lbs.)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator > Page 7123
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator > Page 7124
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> Diagrams > Page 7125
Transfer Case Actuator: Service and Repair
Transfer Case Motor/Encoder Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the front propeller shaft. 4. Remove the motor/encoder electrical connectors.
5. Remove the motor/encoder mounting bolts. 6. Remove the motor/encoder assembly. 7. Remove
the motor/encoder gasket.
Installation Procedure
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Page 7126
Important: ^
If the motor/encoder assembly is being replaced because it is defective, make sure that the transfer
case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench if
necessary.
^ When installing the motor/encoder unit to the transfer case, make sure that the transfer case is
indexed properly and it is flat against the transfer case before tightening the mounting bolts.
1. Install the NEW motor/encoder gasket to the transfer case. 2. Install the motor/encoder to the
transfer case.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install motor/encoder mounting bolts.
^ Tighten the bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
4. Install the motor/encoder electrical connector. Ensure that the retention clips activate. 5. Install
the front propeller shaft. 6. Install the transfer case shield. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Lamps and Indicators Transmission and Drivetrain > Lamps and Indicators - A/T > Shift Indicator > Component Information > Description and
Operation
Shift Indicator: Description and Operation
The IPC displays the vehicle speed based on the vehicle speed signal from the PCM. The PCM
converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The IPC uses the
vehicle speed signal circuit from the PCM in order to calculate the vehicle speed. The speedometer
defaults to 0 km/h (0 mph) if a malfunction in the vehicle speed signal circuit exists.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Lamps and Indicators Transmission and Drivetrain > Lamps and Indicators - Transfer Case > Malfunction Indicator Lamp - Transfer Case >
Component Information > Service and Repair
Malfunction Indicator Lamp - Transfer Case: Service and Repair
Service AWD/4WD Indicator Lamp
Illumination of the Lamp indicates a problem with the drive system. There will probably be a
Transfer Case Code set to aid in diagnostics.
The only way to get the light to go off is to clear Transfer Case codes. This light can NOT be shut
off or reset any other way. Transfer Case codes should be read and repaired before clearing them.
Refer to Transfer Case. See: Transmission and Drivetrain/Transfer Case/Testing and Inspection
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement > Page 7142
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 7145
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 7146
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 7147
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 7148
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 7149
10. Start the engine and test the automatic transfer case system for proper shift operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > 4L60-E > Page 7157
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > Page 7158
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7163
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7164
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7165
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7166
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7167
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Diagrams > 4L60-E > Page 7173
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Adjustments > 4L60-E > Page 7176
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 7179
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 7180
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 7181
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Diagrams > 4L60-E > Page 7187
Transmission Speed Sensor: Diagrams 4L80-E
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E > Page 7190
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
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Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E > Page 7191
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Temperature Sensor/Switch, A/T > Component
Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Technical Service Bulletins > Customer Interest for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr >
02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Four Wheel Drive Selector Switch: >
02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Transfer Case Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Transfer Case Shift Control Switch - C1 > Page 7211
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Page 7212
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Page 7213
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Updated Transfer Case Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Page 7218
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front > Page 7221
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 7224
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 7225
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 7226
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 7227
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 7228
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > PROM - Programmable Read Only Memory > Component
Information > Technical Service Bulletins > Customer Interest: > 04-06-04-040 > Jun > 04 > Fuel System - Low/Rough or
Unstable Idle
PROM - Programmable Read Only Memory: Customer Interest Fuel System - Low/Rough or
Unstable Idle
Bulletin No.: 04-06-04-040
Date: June 14, 2004
TECHNICAL
Subject: Idle Instability, Low or Rough Idle with Electronic Throttle Control (Clean Throttle Body)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC Sierra, Yukon, Yukon XL with 4.8L, 5.3L
or 6.0L V8 Engine (VINs V, T, Z, N, U - RPOs LR4, LM7, L59, LQ9, LQ4) and Electronic Throttle
Control
Condition
Some owners may comment on an idle instability, low idle speed or rough idle.
Cause
Condition may be caused by deposits in the throttle body bore.
Correction
Clean throttle body bore and throttle valve plate of carbon using a shop rag and an appropriate
cleaner. Refer to Engine Controls Repair Procedures - Throttle Body Cleaning Procedure. This
procedure may be performed at any mileage necessary. Check to determine if the PCM calibration
has been previously updated to one that includes the update for throttle body coking. For 2003
model year vehicles, look in the operating system portion of the calibration. For 2000-2002 model
year vehicles, look in the engine portion of the calibration. If not, then update the PCM calibration to
the latest calibration.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > PROM - Programmable Read Only Memory > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for PROM - Programmable Read Only Memory: >
04-06-04-040 > Jun > 04 > Fuel System - Low/Rough or Unstable Idle
PROM - Programmable Read Only Memory: All Technical Service Bulletins Fuel System Low/Rough or Unstable Idle
Bulletin No.: 04-06-04-040
Date: June 14, 2004
TECHNICAL
Subject: Idle Instability, Low or Rough Idle with Electronic Throttle Control (Clean Throttle Body)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2000-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2000-2003 GMC Sierra, Yukon, Yukon XL with 4.8L, 5.3L
or 6.0L V8 Engine (VINs V, T, Z, N, U - RPOs LR4, LM7, L59, LQ9, LQ4) and Electronic Throttle
Control
Condition
Some owners may comment on an idle instability, low idle speed or rough idle.
Cause
Condition may be caused by deposits in the throttle body bore.
Correction
Clean throttle body bore and throttle valve plate of carbon using a shop rag and an appropriate
cleaner. Refer to Engine Controls Repair Procedures - Throttle Body Cleaning Procedure. This
procedure may be performed at any mileage necessary. Check to determine if the PCM calibration
has been previously updated to one that includes the update for throttle body coking. For 2003
model year vehicles, look in the operating system portion of the calibration. For 2000-2002 model
year vehicles, look in the engine portion of the calibration. If not, then update the PCM calibration to
the latest calibration.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > PROM - Programmable Read Only Memory > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for PROM - Programmable Read Only Memory: >
99-06-03-010A > Jun > 01 > PCM/BCM Replacement - DTC's B001/B1271/B1780 Set
PROM - Programmable Read Only Memory: All Technical Service Bulletins PCM/BCM
Replacement - DTC's B001/B1271/B1780 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 99-06-03-010A
Date: June, 2001
INFORMATION
Subject: DTCs B1001, B1271 or B1780 Set When Replacing/Reprogramming Other Modules
Models: 1999-2002 All Passenger Cars and Trucks With Class 2 Serial Data Communication
Between Modules
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
99-06-03-010 (Section 06 - Engine/propulsion System).
Class 2 Serial Data Communication allows control modules (i.e. the Powertrain Control Module
(PCM), the Body Control Module (BCM), the Dash Integration Module (DIM), the Instrument Panel
Cluster (IPC), the radio, the Heating, Ventilation and Air Conditioning (HVAC) Controller, and the
Sensing and Diagnostic Module (SDM) to exchange information. This information may be
operational information or identification information. Among the identification information
exchanged and compared within these modules is the Vehicle Identification Number (VIN).
Typically, the PCM broadcasts a portion of the VIN, while another module broadcasts another
portion of the VIN. This information is compared by the SDM in order to ensure installation is in the
correct vehicle. When the broadcast VIN does not match the VIN stored within the SDM, the
following actions occur:
^ DTC B1001 Option Configuration Error is set and deployment of the airbags is inhibited.
^ The VIN information is also used by the radio in order to prevent theft. When the broadcast VIN
does not match the VIN stored within the radio, a DTC B1271 ora DTC B1780 Theft Locked is set
and the radio is inoperative.
This situation may occur when a vehicle is being repaired. When a PCM or a body control type
module is replaced, the VIN information must be programmed into the replaced (new) control
module. A module which has had VIN information entered into it (for example, one taken from
another vehicle) cannot be reprogrammed. VIN information can only be entered into new modules.
The ignition must be ON in order to program the control module. Since the VIN information is
broadcast when the ignition goes to ON from any other ignition switch position, DTCs may be set in
the SDM and/or the radio. Therefore, always follow the specified control module replacement
procedures.
1. After completing the repair, turn OFF the ignition for at least 30 seconds.
2. Turn ON the ignition and check for DTCs using a scan tool.
If DTCs B1001, B1271, or B178C are present with a history status, DO NOT REPLACE THE SDM
OR THE RADIO.
3. Clear the DTCs from all modules using the scan tool. The SDM and/or the radio should then
operate properly.
4. Ensure the proper operation of the SDM by turning OFF the ignition and then turning ON the
ignition. The air bag warning indicator should flash seven times and then go OFF.
Refer to Corporate Bulletin Number 99-09-41-001 for additional information regarding proper
reprogramming of the new/replaced module.
Clearing codes from the other modules is part of the replacement and reprogramming procedure
for the replaced module. The repair is not complete unless all codes have been cleared from all
modules.
DO NOT SUBMIT CLAIMS FOR OTHER MODULE REPLACEMENTS OR REPROGRAMMING.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Powertrain Management > PROM - Programmable Read Only Memory > Component
Information > Technical Service Bulletins > All Other Service Bulletins for PROM - Programmable Read Only Memory: >
99-06-03-010A > Jun > 01 > PCM/BCM Replacement - DTC's B001/B1271/B1780 Set
PROM - Programmable Read Only Memory: All Technical Service Bulletins PCM/BCM
Replacement - DTC's B001/B1271/B1780 Set
File In Section: 06 - Engine/Propulsion System
Bulletin No.: 99-06-03-010A
Date: June, 2001
INFORMATION
Subject: DTCs B1001, B1271 or B1780 Set When Replacing/Reprogramming Other Modules
Models: 1999-2002 All Passenger Cars and Trucks With Class 2 Serial Data Communication
Between Modules
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
99-06-03-010 (Section 06 - Engine/propulsion System).
Class 2 Serial Data Communication allows control modules (i.e. the Powertrain Control Module
(PCM), the Body Control Module (BCM), the Dash Integration Module (DIM), the Instrument Panel
Cluster (IPC), the radio, the Heating, Ventilation and Air Conditioning (HVAC) Controller, and the
Sensing and Diagnostic Module (SDM) to exchange information. This information may be
operational information or identification information. Among the identification information
exchanged and compared within these modules is the Vehicle Identification Number (VIN).
Typically, the PCM broadcasts a portion of the VIN, while another module broadcasts another
portion of the VIN. This information is compared by the SDM in order to ensure installation is in the
correct vehicle. When the broadcast VIN does not match the VIN stored within the SDM, the
following actions occur:
^ DTC B1001 Option Configuration Error is set and deployment of the airbags is inhibited.
^ The VIN information is also used by the radio in order to prevent theft. When the broadcast VIN
does not match the VIN stored within the radio, a DTC B1271 ora DTC B1780 Theft Locked is set
and the radio is inoperative.
This situation may occur when a vehicle is being repaired. When a PCM or a body control type
module is replaced, the VIN information must be programmed into the replaced (new) control
module. A module which has had VIN information entered into it (for example, one taken from
another vehicle) cannot be reprogrammed. VIN information can only be entered into new modules.
The ignition must be ON in order to program the control module. Since the VIN information is
broadcast when the ignition goes to ON from any other ignition switch position, DTCs may be set in
the SDM and/or the radio. Therefore, always follow the specified control module replacement
procedures.
1. After completing the repair, turn OFF the ignition for at least 30 seconds.
2. Turn ON the ignition and check for DTCs using a scan tool.
If DTCs B1001, B1271, or B178C are present with a history status, DO NOT REPLACE THE SDM
OR THE RADIO.
3. Clear the DTCs from all modules using the scan tool. The SDM and/or the radio should then
operate properly.
4. Ensure the proper operation of the SDM by turning OFF the ignition and then turning ON the
ignition. The air bag warning indicator should flash seven times and then go OFF.
Refer to Corporate Bulletin Number 99-09-41-001 for additional information regarding proper
reprogramming of the new/replaced module.
Clearing codes from the other modules is part of the replacement and reprogramming procedure
for the replaced module. The repair is not complete unless all codes have been cleared from all
modules.
DO NOT SUBMIT CLAIMS FOR OTHER MODULE REPLACEMENTS OR REPROGRAMMING.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Specifications
Pressure Regulating Solenoid: Specifications
4L60-E
Pressure Control Solenoid Bracket to Valve Body Bolt .......................................................................
.......................................................................................................... 8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Pressure Control Solenoid Bracket to Valve Body ..............................................................................
...................................................................................................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Diagrams > 4L60-E
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page
7259
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair >
4L60-E
Pressure Regulating Solenoid: Service and Repair 4L60-E
Pressure Regulator Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
filter. 3. Compress the reverse boost valve sleeve into the bore of the oil pump to release tension
on the reverse boost valve retaining ring. 4. Remove the reverse boost valve retaining ring, then
slowly release tension on the reverse boost valve sleeve.
5. Remove the reverse boost valve sleeve (5) and the reverse boost valve (4). 6. Remove the
pressure regulator isolator spring (3) and the pressure regulator valve spring (2). 7. Remove the
pressure regulator valve (1).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7262
1. Install the pressure regulator valve (1). 2. Install the pressure regulator isolator spring (3) and the
pressure regulator valve spring (2). 3. Install the reverse boost valve (4) in the reverse boost valve
sleeve (5). 4. Install the reverse boost valve (4) and sleeve (5) in the oil pump cover.
5. Compress the reverse boost valve sleeve into the bore of the oil pump to expose the retaining
ring slot. 6. Install the reverse boost valve retaining ring, then slowly release tension on the reverse
boost valve sleeve. 7. Install the transmission oil filter and pan. 8. Lower the vehicle. 9. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7263
Pressure Regulating Solenoid: Service and Repair 4L80-E
Pressure Regulator Replacement
^ Tools Required J 36850 Transjel
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the reverse boost valve bushing retainer ring (2).
4. Remove the following from the reverse boost valve cylinder:
^ The reverse boost valve bushing
^ The reverse boost valve
^ The pressure regulator spring retainer
^ The pressure regulator spring
^ The pressure regulator valve
^ The reverse boost valve bushing
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7264
1. Install the pressure regulator valve with J 36850. 2. Pre-assemble the following parts:
^ The reverse boost valve bushing
^ A new reverse boost valve
^ A new pressure regulator spring retainer
^ The added isolator pressure regulator spring
^ The pressure regulator spring
3. Install the pre-assembled parts into the pump bore.
4. Install the reverse boost valve bushing retainer ring while holding the reverse boost valve
bushing in place.
Ensure the retainer ring (2) is in the groove.
5. Install the transmission oil pan and the oil filter. 6. Lower the vehicle. 7. Fill the transmission to
the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams > Page 7268
Shift Interlock Solenoid: Service and Repair
Automatic Transmission Shift Lock Actuator Replacement
Removal Procedure
Caution: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the body control module bracket. 3. Put the shift lever clevis
into the neutral position. 4. Disconnect the electrical connector. 5. Use a small screwdriver to pry
the automatic transmission shift lock control actuator away from the steering column jacket
assembly and the cable
shift cam assembly.
6. Remove the automatic transmission shift lock control actuator.
Installation Procedure
1. Firmly install the automatic transmission shift lock control actuator onto the steering column
jacket assembly and the cable shift cam assembly. 2. Connect the electrical connector
3. Adjust the automatic transmission shift lock control actuator (with the shift lever clevis in the
neutral position) in the following way:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams > Page 7269
3.1. Pull out the tab (1) on the adjuster block side (2) of the automatic transmission shift lock
control actuator.
3.2. Press on the adjuster block (2) to compress the internal adjuster spring, which disengages the
adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible.
3.3. Lock the adjuster block (2) in place by pushing in on the tab (1).
4. Inspect the automatic transmission shift lock control actuator for the following items:
4.1. The automatic transmission shift lock control actuator must lock the shift lever clevis when the
shift lever clevis is put into the park position.
4.2. Depress the brake pedal to move the shift lever out of the park position.
4.3. The actuator will be energized.
4.4. Readjust the automatic transmission shift lock control actuator if needed.
5. Install the body control module bracket. 6. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Specifications
Shift Solenoid: Specifications
4L80-E
Solenoid to Valve Body .......................................................................................................................
............................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > 4L60-E
Shift Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7275
Shift Solenoid: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7276
Shift Solenoid: Service and Repair
Control and Shift Solenoids Replacement
Removal Procedure
1. Remove the transmission oil pan and filter.
Important: Do not remove the valve body for the following procedures. Removal of the 1-2
accumulator is necessary only if servicing the pressure control solenoid.
2. Remove the 1-2 accumulator if necessary. 3. Disconnect the internal wiring harness electrical
connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
4. Remove the pressure control solenoid retainer. 5. Remove the pressure control solenoid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7277
6. Remove the 1-2 and 2-3 shift solenoid retainers. 7. Remove the 1-2 and 2-3 shift solenoids.
8. Remove the 3-2 control solenoid retainer. 9. Remove the 3-2 control solenoid.
Installation Procedure
1. Install the 3-2 control solenoid. 2. Install the 3-2 control solenoid retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7278
3. Install the 1-2 and 2-3 shift solenoids. 4. Install the 1-2 and 2-3 shift solenoid retainers.
5. Install the pressure control solenoid. Ensure that the electrical tabs are facing outboard.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
7. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
8. Install the 1-2 accumulator. 9. Install the transmission oil pan and filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7279
10. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Specifications
Torque Converter Clutch Solenoid: Specifications
4L60-E
TCC Solenoid Assembly to Case Bolt
..................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E
Torque Converter Clutch Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E >
Page 7285
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E
Torque Converter Clutch Solenoid: Service and Repair 4L60-E
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid, TCC Solenoid, and Wiring
Harness
^ Tools Required J 28458 Seal Protector Retainer Installer
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
the filter. 3. Disconnect the transmission harness 20-way connector from the transmission internal
harness pass-through connector.
Depress both tabs on the connector and pull straight up; do not pry the connector.
Important: Removal of the valve body is not necessary for the following procedure.
4. Remove the 1-2 accumulator assembly. Do not remove the spacer plate.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7288
6. Remove the TCC PWM solenoid retainer. 7. Remove the TCC PWM solenoid in order to access
one of the TCC solenoid retaining bolts.
8. Remove the pressure control solenoid retainer. 9. Remove the pressure control solenoid.
10. Remove the TCC solenoid retaining bolts and the valve body bolts, which retain the internal
wiring harness.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7289
11. Using J28458, release the pass-through electrical connector from the transmission case.
11.1. Use the small end of the J28458 over the top of the connector.
11.2. Twist in order to release the four tabs retaining the connector.
11.3. Pull the harness connector down through the transmission case.
12. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the
transmission case.
13. Inspect the TCC solenoid and wiring harness assembly for the following defects:
^ Damage
^ Cracked connectors
^ Exposed wires
^ Loose pins
Installation Procedure
1. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the
transmission. 2. Install the pass-through electrical connector to the transmission case.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7290
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the valve body bolts, which retain the internal wiring harness and install the TCC solenoid
retaining bolts.
^ Tighten the control valve body retaining bolts to 11 Nm (97 inch lbs.).
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
4. Install the pressure control solenoid.
Ensure that the electrical tabs are facing outboard.
5. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
6. Install the TCC PWM solenoid to the control valve body. 7. Install the TCC PWM solenoid
retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7291
8. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
9. Install the 1-2 accumulator.
10. Connect the transmission harness 20-way connector to the transmission pass-through
connector.
Align the arrows on each half of the connector and insert straight down.
11. Install the transmission oil pan and filter. 12. Lower the vehicle. 13. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7292
Torque Converter Clutch Solenoid: Service and Repair 4L80-E
Torque Converter Clutch (TCC) Valve and Spring Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the oil filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the valve bore plug retainer ring (1).
4. Remove the following parts:
^ The valve bore plug
^ The TCC valve
^ The TCC valve spring
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair >
4L60-E > Page 7293
1. Install the following parts:
^ The TCC valve spring
^ The TCC valve
^ The valve bore plug
2. Install the valve bore plug retainer ring (1). 3. Install the transmission oil pan and oil filter. 4.
Lower the vehicle. 5. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Specifications
Transfer Case Actuator: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (14 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Diagrams > Front Axle
Actuator
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Diagrams > Front Axle
Actuator > Page 7300
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Diagrams > Front Axle
Actuator > Page 7301
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Diagrams > Page 7302
Transfer Case Actuator: Service and Repair
Transfer Case Motor/Encoder Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the front propeller shaft. 4. Remove the motor/encoder electrical connectors.
5. Remove the motor/encoder mounting bolts. 6. Remove the motor/encoder assembly. 7. Remove
the motor/encoder gasket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Actuators and Solenoids - Transmission and Drivetrain >
Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information > Diagrams > Page 7303
Important: ^
If the motor/encoder assembly is being replaced because it is defective, make sure that the transfer
case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench if
necessary.
^ When installing the motor/encoder unit to the transfer case, make sure that the transfer case is
indexed properly and it is flat against the transfer case before tightening the mounting bolts.
1. Install the NEW motor/encoder gasket to the transfer case. 2. Install the motor/encoder to the
transfer case.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install motor/encoder mounting bolts.
^ Tighten the bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
4. Install the motor/encoder electrical connector. Ensure that the retention clips activate. 5. Install
the front propeller shaft. 6. Install the transfer case shield. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Specifications
Pressure Regulating Solenoid: Specifications
4L60-E
Pressure Control Solenoid Bracket to Valve Body Bolt .......................................................................
.......................................................................................................... 8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Pressure Control Solenoid Bracket to Valve Body ..............................................................................
...................................................................................................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Diagrams > 4L60-E
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7311
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair > 4L60-E
Pressure Regulating Solenoid: Service and Repair 4L60-E
Pressure Regulator Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
filter. 3. Compress the reverse boost valve sleeve into the bore of the oil pump to release tension
on the reverse boost valve retaining ring. 4. Remove the reverse boost valve retaining ring, then
slowly release tension on the reverse boost valve sleeve.
5. Remove the reverse boost valve sleeve (5) and the reverse boost valve (4). 6. Remove the
pressure regulator isolator spring (3) and the pressure regulator valve spring (2). 7. Remove the
pressure regulator valve (1).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7314
1. Install the pressure regulator valve (1). 2. Install the pressure regulator isolator spring (3) and the
pressure regulator valve spring (2). 3. Install the reverse boost valve (4) in the reverse boost valve
sleeve (5). 4. Install the reverse boost valve (4) and sleeve (5) in the oil pump cover.
5. Compress the reverse boost valve sleeve into the bore of the oil pump to expose the retaining
ring slot. 6. Install the reverse boost valve retaining ring, then slowly release tension on the reverse
boost valve sleeve. 7. Install the transmission oil filter and pan. 8. Lower the vehicle. 9. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7315
Pressure Regulating Solenoid: Service and Repair 4L80-E
Pressure Regulator Replacement
^ Tools Required J 36850 Transjel
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the reverse boost valve bushing retainer ring (2).
4. Remove the following from the reverse boost valve cylinder:
^ The reverse boost valve bushing
^ The reverse boost valve
^ The pressure regulator spring retainer
^ The pressure regulator spring
^ The pressure regulator valve
^ The reverse boost valve bushing
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7316
1. Install the pressure regulator valve with J 36850. 2. Pre-assemble the following parts:
^ The reverse boost valve bushing
^ A new reverse boost valve
^ A new pressure regulator spring retainer
^ The added isolator pressure regulator spring
^ The pressure regulator spring
3. Install the pre-assembled parts into the pump bore.
4. Install the reverse boost valve bushing retainer ring while holding the reverse boost valve
bushing in place.
Ensure the retainer ring (2) is in the groove.
5. Install the transmission oil pan and the oil filter. 6. Lower the vehicle. 7. Fill the transmission to
the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams > Page 7320
Shift Interlock Solenoid: Service and Repair
Automatic Transmission Shift Lock Actuator Replacement
Removal Procedure
Caution: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the body control module bracket. 3. Put the shift lever clevis
into the neutral position. 4. Disconnect the electrical connector. 5. Use a small screwdriver to pry
the automatic transmission shift lock control actuator away from the steering column jacket
assembly and the cable
shift cam assembly.
6. Remove the automatic transmission shift lock control actuator.
Installation Procedure
1. Firmly install the automatic transmission shift lock control actuator onto the steering column
jacket assembly and the cable shift cam assembly. 2. Connect the electrical connector
3. Adjust the automatic transmission shift lock control actuator (with the shift lever clevis in the
neutral position) in the following way:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Interlock Solenoid > Component Information > Diagrams > Page 7321
3.1. Pull out the tab (1) on the adjuster block side (2) of the automatic transmission shift lock
control actuator.
3.2. Press on the adjuster block (2) to compress the internal adjuster spring, which disengages the
adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible.
3.3. Lock the adjuster block (2) in place by pushing in on the tab (1).
4. Inspect the automatic transmission shift lock control actuator for the following items:
4.1. The automatic transmission shift lock control actuator must lock the shift lever clevis when the
shift lever clevis is put into the park position.
4.2. Depress the brake pedal to move the shift lever out of the park position.
4.3. The actuator will be energized.
4.4. Readjust the automatic transmission shift lock control actuator if needed.
5. Install the body control module bracket. 6. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Specifications
Shift Solenoid: Specifications
4L80-E
Solenoid to Valve Body .......................................................................................................................
............................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > 4L60-E
Shift Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7327
Shift Solenoid: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7328
Shift Solenoid: Service and Repair
Control and Shift Solenoids Replacement
Removal Procedure
1. Remove the transmission oil pan and filter.
Important: Do not remove the valve body for the following procedures. Removal of the 1-2
accumulator is necessary only if servicing the pressure control solenoid.
2. Remove the 1-2 accumulator if necessary. 3. Disconnect the internal wiring harness electrical
connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
4. Remove the pressure control solenoid retainer. 5. Remove the pressure control solenoid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7329
6. Remove the 1-2 and 2-3 shift solenoid retainers. 7. Remove the 1-2 and 2-3 shift solenoids.
8. Remove the 3-2 control solenoid retainer. 9. Remove the 3-2 control solenoid.
Installation Procedure
1. Install the 3-2 control solenoid. 2. Install the 3-2 control solenoid retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7330
3. Install the 1-2 and 2-3 shift solenoids. 4. Install the 1-2 and 2-3 shift solenoid retainers.
5. Install the pressure control solenoid. Ensure that the electrical tabs are facing outboard.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
7. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
8. Install the 1-2 accumulator. 9. Install the transmission oil pan and filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams > Page 7331
10. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Specifications
Torque Converter Clutch Solenoid: Specifications
4L60-E
TCC Solenoid Assembly to Case Bolt
..................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E
Torque Converter Clutch Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7337
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E
Torque Converter Clutch Solenoid: Service and Repair 4L60-E
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid, TCC Solenoid, and Wiring
Harness
^ Tools Required J 28458 Seal Protector Retainer Installer
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
the filter. 3. Disconnect the transmission harness 20-way connector from the transmission internal
harness pass-through connector.
Depress both tabs on the connector and pull straight up; do not pry the connector.
Important: Removal of the valve body is not necessary for the following procedure.
4. Remove the 1-2 accumulator assembly. Do not remove the spacer plate.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7340
6. Remove the TCC PWM solenoid retainer. 7. Remove the TCC PWM solenoid in order to access
one of the TCC solenoid retaining bolts.
8. Remove the pressure control solenoid retainer. 9. Remove the pressure control solenoid.
10. Remove the TCC solenoid retaining bolts and the valve body bolts, which retain the internal
wiring harness.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7341
11. Using J28458, release the pass-through electrical connector from the transmission case.
11.1. Use the small end of the J28458 over the top of the connector.
11.2. Twist in order to release the four tabs retaining the connector.
11.3. Pull the harness connector down through the transmission case.
12. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the
transmission case.
13. Inspect the TCC solenoid and wiring harness assembly for the following defects:
^ Damage
^ Cracked connectors
^ Exposed wires
^ Loose pins
Installation Procedure
1. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the
transmission. 2. Install the pass-through electrical connector to the transmission case.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7342
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the valve body bolts, which retain the internal wiring harness and install the TCC solenoid
retaining bolts.
^ Tighten the control valve body retaining bolts to 11 Nm (97 inch lbs.).
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
4. Install the pressure control solenoid.
Ensure that the electrical tabs are facing outboard.
5. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
6. Install the TCC PWM solenoid to the control valve body. 7. Install the TCC PWM solenoid
retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7343
8. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
9. Install the 1-2 accumulator.
10. Connect the transmission harness 20-way connector to the transmission pass-through
connector.
Align the arrows on each half of the connector and insert straight down.
11. Install the transmission oil pan and filter. 12. Lower the vehicle. 13. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7344
Torque Converter Clutch Solenoid: Service and Repair 4L80-E
Torque Converter Clutch (TCC) Valve and Spring Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the oil filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the valve bore plug retainer ring (1).
4. Remove the following parts:
^ The valve bore plug
^ The TCC valve
^ The TCC valve spring
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Actuators and
Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page
7345
1. Install the following parts:
^ The TCC valve spring
^ The TCC valve
^ The valve bore plug
2. Install the valve bore plug retainer ring (1). 3. Install the transmission oil pan and oil filter. 4.
Lower the vehicle. 5. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Technical Service Bulletins > Customer Interest for Band Apply Servo: > 04-07-30-028A > Jan
> 06 > A/T - 4T65-E Fluid Leaks From Reverse Servo Cover
Band Apply Servo: Customer Interest A/T - 4T65-E Fluid Leaks From Reverse Servo Cover
Bulletin No.: 04-07-30-028A
Date: January 12, 2006
TECHNICAL
Subject: 4T65-E Automatic Transmission Fluid Leak From Reverse Servo Cover (Replace Reverse
Servo Cover Seal)
Models: 2005 and Prior Cars and Light Duty Trucks
with Automatic Transmission 4T65-E (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to announce an improved reverse servo cover seal is available from
GMSPO and to advise technicians that it is no longer necessary to replace the reverse servo cover
when replacing the seal. The 2005 model year vehicles are also being added. Please discard
Corporate Bulletin Number 04-07-30-028 (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a fluid leak under the vehicle. A transmission fluid leak may be
noted during the Pre-delivery Inspection (PDI).
Cause
A possible cause of a transmission fluid leak usually only during cold ambient temperatures below
-6.7°C (20°F) may be the reverse servo cover seal. The reverse servo cover seal may shrink in
cold ambient temperatures causing a transmission fluid leak.
Correction
Follow the diagnosis and repair procedure below to correct this condition.
1. Diagnose the source of the fluid leak.
2. If the source of the transmission fluid leak is the reverse servo cover, replace the reverse servo
cover seal with P/N 24235894. Refer to Reverse Servo Replacement in the appropriate Service
Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Technical Service Bulletins > Customer Interest for Band Apply Servo: > 04-07-30-028A > Jan
> 06 > A/T - 4T65-E Fluid Leaks From Reverse Servo Cover > Page 7354
3. Clean the area around and below the cover.
4. Inspect the transmission fluid level. Refer to Transmission Fluid Checking Procedure in the
appropriate Service Manual.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Band Apply Servo: >
04-07-30-028A > Jan > 06 > A/T - 4T65-E Fluid Leaks From Reverse Servo Cover
Band Apply Servo: All Technical Service Bulletins A/T - 4T65-E Fluid Leaks From Reverse Servo
Cover
Bulletin No.: 04-07-30-028A
Date: January 12, 2006
TECHNICAL
Subject: 4T65-E Automatic Transmission Fluid Leak From Reverse Servo Cover (Replace Reverse
Servo Cover Seal)
Models: 2005 and Prior Cars and Light Duty Trucks
with Automatic Transmission 4T65-E (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to announce an improved reverse servo cover seal is available from
GMSPO and to advise technicians that it is no longer necessary to replace the reverse servo cover
when replacing the seal. The 2005 model year vehicles are also being added. Please discard
Corporate Bulletin Number 04-07-30-028 (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a fluid leak under the vehicle. A transmission fluid leak may be
noted during the Pre-delivery Inspection (PDI).
Cause
A possible cause of a transmission fluid leak usually only during cold ambient temperatures below
-6.7°C (20°F) may be the reverse servo cover seal. The reverse servo cover seal may shrink in
cold ambient temperatures causing a transmission fluid leak.
Correction
Follow the diagnosis and repair procedure below to correct this condition.
1. Diagnose the source of the fluid leak.
2. If the source of the transmission fluid leak is the reverse servo cover, replace the reverse servo
cover seal with P/N 24235894. Refer to Reverse Servo Replacement in the appropriate Service
Manual.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Band Apply Servo: >
04-07-30-028A > Jan > 06 > A/T - 4T65-E Fluid Leaks From Reverse Servo Cover > Page 7360
3. Clean the area around and below the cover.
4. Inspect the transmission fluid level. Refer to Transmission Fluid Checking Procedure in the
appropriate Service Manual.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Technical Service Bulletins > Page 7361
Band Apply Servo: Specifications
4L80-E
Rear Servo Cover to Case ..................................................................................................................
................................................... 24 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E
Band Apply Servo: Service and Repair 4L60-E
2-4 Servo
^ Tools Required J 29714-A Servo Cover Depressor
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the exhaust pipe assembly. 3. Remove the
heat shield.
4. Install the J29714-A. 5. Tighten the bolt in order to compress the servo cover.
6. Remove the servo cover retaining ring. 7. Remove the J 29714-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E > Page 7364
8. Remove the servo cover and the O-ring seal. If the cover is hung up on the seal, use a pick (2)
to pull and stretch the seal (1) out of the groove. Cut
and remove the O-ring seal before removing the cover.
9. Remove the 2-4 servo from the transmission.
10. Inspect the 4th apply piston, 2-4 servo converter, 2nd apply piston, and the servo piston inner
housing for the following defects.
^ Cracks
^ Scoring
^ Burrs and nicks
Installation Procedure
1. Install new seals on the servo pistons and the servo cover. 2. Install the 2-4 servo assembly into
the transmission. 3. Install the J29714-A.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E > Page 7365
4. Tighten the bolt in order to compress the servo cover. 5. Install the servo cover retaining ring. 6.
Remove the J29714-A from the oil pan flange.
Notice: Refer to Fastener Notice in Service Precautions.
7. Install the oil pan bolt.
^ Tighten the oil pan bolt to 11 Nm (97 inch lbs.).
8. Install the heat shield. 9. Install the two bolts securing the transmission heat shield to the
transmission.
^ Tighten the bolts to 17 Nm (13 ft. lbs.).
10. Install the exhaust pipe assembly. 11. Lower the vehicle. 12. Fill the transmission to the proper
level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E > Page 7366
Band Apply Servo: Service and Repair 4L80-E
Reverse Servo Replacement
Reverse Servo Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and filter. 3.
Remove the rear servo assembly from the transmission case as follows:
^ Cover bolts (6)
^ Cover (5)
^ Cover gasket (4)
^ Bottom retaining clip (3)
^ Servo piston (2)
^ Outer ring oil seal (1)
^ Inner ring oil seal (7)
^ Accumulator piston (8)
^ Piston seal (9)
^ Washer (10)
^ Servo spring (11)
^ Servo spring retainer (12)
^ Selective pin (13)
^ Accumulator spring (14)
Installation Procedure
1. Install the rear servo assembly to the transmission case as follows:
^ Accumulator spring (14)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E > Page 7367
^ Selective pin (13)
^ Servo spring retainer (12)
^ Servo spring (11)
^ Washer (10)
^ Piston seal (9)
^ Accumulator piston (8)
^ Inner ring oil seal (7)
^ Outer ring oil seal (1)
^ Servo piston (2)
^ Bottom retaining clip (3)
^ Cover gasket (4)
^ Cover (5)
^ Cover Bolt (6)
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the cover bolts (61).
^ Tighten the bolts to 24 Nm (18 ft. lbs.).
3. Install the transmission oil pan and filter. 4. Lower the vehicle. 5. Fill the transmission to the
proper level with DEXRON III transmission fluid.
Forward Servo Replacement
Forward Servo Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the oil pan and filter. 3. Remove the six
forward servo cover bolts, cover, and gasket. 4. Remove the following parts:
4.1. Forward servo piston pin (5)
4.2. O-ring seal (4)
4.3. Servo piston (3)
4.4. Retainer (2)
4.5. Piston spring (1)
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Band Apply Servo, A/T
> Component Information > Service and Repair > 4L60-E > Page 7368
1. Install the following parts:
^ Piston spring (1)
^ Retainer (2)
^ Servo piston (3)
^ O-ring seal (4)
^ Forward servo piston pin (5)
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the forward servo gasket, cover, and bolts.
^ Tighten the bolts to 24 Nm (18 ft. lbs.).
3. Install the oil pan and filter. 4. Lower the vehicle. 5. Fill the transmission to the proper level with
DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Bell Housing, A/T >
Component Information > Specifications
Bell Housing: Specifications
4L60-E
Converter Housing to Case Screw
........................................................................................................................................ 65.0-75.0
Nm (48-55 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis
Case: Technical Service Bulletins A/T - Cracked Case Diagnosis
Bulletin No.: 02-07-30-024B
Date: August 18, 2005
INFORMATION
Subject: Diagnosis of Cracked or Broken Transmission Case
Models: 2006 and Prior Cars and Light Duty Trucks 2006 and Prior HUMMER H2 2006 HUMMER
H3 2005-2006 Saab 9-7X
with 4L60/4L60-E/4L65-E or 4L80-E/4L85-E or Allison(R) Series 1000 Automatic Transmission
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 02-07-30-024A (Section 07 - Transmission/Transaxle).
Diagnosing the cause of a cracked or broken transmission case requires additional diagnosis and
repair or a repeat failure will occur.
A cracked or broken transmission case is most often the result of abnormal external torsional
forces acting on the transmission case. If none of the conditions listed below are apparent, an
internal transmission component inspection may be required. Repairs of this type may be the result
of external damage or abuse for which General Motors is not responsible. They are not the result of
defects in materials or workmanship. If in doubt, contact your General Motors Service
Representative.
The following items should be considered:
^ It is important to inspect the vehicle for signs of an out of line condition, impact damage or foreign
material to the following components:
- The transmission
- The engine mounts
- The transmission rear mount and crossmember
- Vehicle frame damage that alters the front to rear alignment of the driveshaft
- The driveshafts (both front and rear)
- The wheels (caked with mud, concrete, etc.)
- The tires (roundness, lack of cupping, excessive balance weights)
- The transfer case (if the vehicle is 4WD)
^ A worn or damaged driveshaft U-Joint has shown to be a frequent cause of transmission case
cracking, especially on vehicles that see extended periods of highway driving. Always inspect the
U-joint condition when diagnosing this condition.
^ For driveshaft damage or imbalance, Inspect the driveshafts (both front and rear) for dents,
straightness/runout or signs of missing balance weights. Also, inspect for foreign material such as
undercoat sprayed on the driveshaft.
^ The driveshaft working angles may be excessive or non-canceling, especially if the vehicle
carrying height has been altered (lifted or lowered) or if the frame has been extended or modified.
^ Damaged or worn upper or lower rear control arms or bushings.
^ A rear axle that is not seated in the rear spring properly (leaf spring vehicles).
^ Broken rear springs and or worn leaf spring bushings.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7376
In some cases, the customer may not comment about a vibration but it is important to test drive the
vehicle while using the electronic vibration analysis tool in an attempt to locate the cause of the
torsional vibration. Refer to the Vibration Diagnosis and Correction sub-section of the appropriate
Service Manual for more details on diagnosing and correcting vibrations.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7377
Case: Technical Service Bulletins A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service
Bulletin No.: 04-07-30-023
Date: May 12, 2004
INFORMATION
Subject: Oil Pump Assembly Seal and Transmission Case Change
Models: 2002-2004 Cars and Light Duty Trucks with 4L60-E or 4L65-E Automatic Transmissions
(RPOs M30, M32 or M33)
An improved oil pump to case seal design has been made to the 4L60-E/4L65-E transmission. The
new design affects the oil pump, the oil pump seal, the transmission pan bolts and the transmission
case. The complete design was implemented in three phases.
The first phase, beginning in September 2002, relocated the machining of the oil pump 0-ring seal
groove in the pump body. The 0-ring seal groove moved 1.6 mm (0.62 in) inward on the pump body
in order to place the sealing surface deeper into the case bore. The relocated pump body groove
can be identified by measuring the groove location. Pump bodies that measure 2.3 mm (0.09 in)
from the machined surface to the groove opening have the relocated 0-ring seal groove. Pump
bodies that measure 3.9 mm (0.15 in) are prior to September 2002 design.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7378
The first phase also machined a case chamfer leading into the pump bore (2). The chamfer is
designed to help eliminate possible 0-ring seal damage during pump installation.
Phase two modified the case casting and the chamfer into the pump bore. The casting change left
additional material in the surrounding pump bore to allow deeper bore machining in order to create
the necessary sealing surface for a new pump seal design. The leading surface into the pump bore
was also machined with a modified chamfer (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7379
Phase three will eliminate the oil pump body 0-ring seal groove and the 0-ring seal. Beginning
March 2004, a new stamped carrier molded rubber seal (2) will be used to seal the pump assembly
to the transmission case.
The pump sealing surface is now the outer diameter of the pump and the inner diameter (1) of the
transmission case bore. Unlike the current 0-ring seal, which is installed on the oil pump body, the
new seal is installed after the pump assembly is properly positioned and torqued in place. Seating
the seal is accomplished when the torque converter housing is installed, which presses the seal (3)
into position between the pump and the case bore (1).
As a result of the modified casting and the deeper pump bore machining, the area between the oil
pan mounting surface and the pump bore has decreased. Because of the reduced material in this
area (1) it is necessary to use the shorter oil pan attaching bolts (2). Early pan bolts (3), before
November 2002, should not be used with the modified case design, since they are 1.0 mm (0.39 in)
longer and could deform the chamfer surface (4).
Service Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7380
When Servicing transmissions with the new seal design, use the following precautions:
^ The outer diameter of the pump assembly and case bore must be clean and free of burrs or
raised surfaces. Be aware of sharp edges that could damage the seal during installation.
^ The seal should be clean and dry before installation. It does not require lubrication for installation.
^ The seal should be inspected prior to installation for obvious damage.
^ It is preferable to hand-start the seal positioning the seal evenly around the case bore before
installing the torque converter housing.
^ The seal can be easily removed by prying it out, typical of a pressed-on seal.
^ The seal may be reused, however a thorough inspection must be performed. Inspect the seal for
the following conditions:
^ Distortion of the metal carrier or separation from the rubber seal.
^ A cut, deformed, or damaged seal.
^ Refer to the appropriate unit repair information in SI for seal removal and installation procedures.
Parts Interchangeability Information
In order to properly service the different designs, it is necessary to correctly identify and select
corresponding parts for each level. This table provides a summary of the part usage for the
different design levels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > A/T - Cracked Case Diagnosis > Page 7381
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Technical Service Bulletins > Page 7382
Case: Specifications
4L60-E
Case Extension to Case Bolt
................................................................................................................................................
42.0-48.0 Nm (31-35 ft. lbs.) Case Extension to Case Bolt (4WD Shipping) ......................................
......................................................................................................................... 11.2-22.6 Nm
(8.3-16.7 ft. lbs.)
4L80-E
Case Center Support ...........................................................................................................................
.................................................. 43 Nm (32 ft. lbs.) Transmission Case to Engine .............................
................................................................................................................................... 44 Nm (32 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Service and Repair > Heat Shield Replacement - 4L80-E
Case: Service and Repair Heat Shield Replacement - 4L80-E
Heat Shield Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the two bolts securing the transmission
heat shield to the cross member. 3. Remove the transmission heat shield from the cross member.
Installation Procedure
1. Install the transmission heat shield to the cross member.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the two bolts securing the transmission heat shield to the cross member.
^ Tighten the bolts to 17 Nm (13 ft. lbs.).
3. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Case, A/T >
Component Information > Service and Repair > Heat Shield Replacement - 4L80-E > Page 7385
Case: Service and Repair Vent Hose - 4L80-E
Vent Hose
Removal Procedure
1. Remove the vent hose clip. 2. Remove the vent hose from the transmission vent.
Installation Procedure
1. Install the vent hose to the transmission. 2. Install the vent hose to the clip.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt and the clamp.
^ Tighten the bolt to 10 Nm (89 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > Customer Interest: > 01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid
Leaking From A/T Vent
Channel Plate: Customer Interest A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > Customer Interest: > 01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid
Leaking From A/T Vent > Page 7394
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Channel Plate: > 01-07-30-036H
> Jan > 09 > A/T Control - DTC P0756 Diagnostic Tips
Channel Plate: All Technical Service Bulletins A/T Control - DTC P0756 Diagnostic Tips
INFORMATION
Bulletin No.: 01-07-30-036H
Date: January 29, 2009
Subject: Diagnostic Tips for Automatic Transmission DTC P0756, Second, Third, Fourth Gear Start
Models: 2009 and Prior GM Passenger Cars and Light Duty Trucks 2009 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
with 4L60-E, 4L65-E or 4L70E Automatic Transmission (RPOs M30, M32 or M70)
Supercede:
This bulletin is being revised to add the 2009 model year and add details regarding spacer plates.
Please discard Corporate Bulletin Number 01-07-30-036G (Section 07 - Transmission/Transaxle).
Some dealership technicians may have difficulty diagnosing DTC P0756, 2-3 Shift Valve
Performance on 4L60-E, 4L65-E or 4L70E automatic transmissions. As detailed in the Service
Manual, when the PCM detects a 4-3-3-4 shift pattern, DTC P0756 will set. Some customers may
also describe a condition of a second, third or fourth gear start that may have the same causes but
has not set this DTC yet. Below are some tips when diagnosing this DTC:
^ This is a performance code. This means that a mechanical malfunction exists.
^ This code is not set by electrical issues such as a damaged wiring harness or poor electrical
connections. Electrical problems would cause a DTC P0758, P0787 or P0788 to set.
^ The most likely cause is chips/debris plugging the filtered AFL oil at orifice # 29 on the top of the
spacer plate (48). This is a very small hole and is easily plugged by a small amount of debris. It is
important to remove the spacer plate and inspect orifice # 29 and the immediate area for the
presence of chips/debris. Also, the transmission case passage directly above this orifice and the
valve body passage directly below should be inspected and cleaned of any chips/debris. For 2003
and newer vehicles the spacer plate should be replaced. The service replacement spacer plate is a
bonded style with gaskets and solenoid filter screens bonded to the spacer plate. These screens
can help to prevent plugging of orifice # 29 caused by small debris or chips.
^ This code could be set if the 2-3 shift valve (368) were stuck or hung-up in its bore. Inspect the
2-3 shift valve (368) and the 2-3 shuttle valve (369) for free movement or damage and clean the
valves, the bore and the valve body passages.
^ This code could be set by a 2-3 shift solenoid (367b) if it were cracked, broken or leaking. Refer
to Shift Solenoid Leak Test in the appropriate Service Manual for the leak test procedure. Based on
parts return findings, a damaged or leaking shift solenoid is the least likely cause of this condition.
Simply replacing a shift solenoid will not correct this condition unless the solenoid has been found
to be cracked, broken or leaking.
It is important to also refer to the appropriate Service Manual or Service Information (SI) for further
possible causes of this condition.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Channel Plate: > 01-07-30-032E
> Sep > 08 > A/T - 4T65E Fluid Leaking From A/T Vent
Channel Plate: All Technical Service Bulletins A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Channel Plate: > 01-07-30-032E
> Sep > 08 > A/T - 4T65E Fluid Leaking From A/T Vent > Page 7404
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Channel Plate: > 01-07-30-036H >
Jan > 09 > A/T Control - DTC P0756 Diagnostic Tips
Channel Plate: All Technical Service Bulletins A/T Control - DTC P0756 Diagnostic Tips
INFORMATION
Bulletin No.: 01-07-30-036H
Date: January 29, 2009
Subject: Diagnostic Tips for Automatic Transmission DTC P0756, Second, Third, Fourth Gear Start
Models: 2009 and Prior GM Passenger Cars and Light Duty Trucks 2009 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
with 4L60-E, 4L65-E or 4L70E Automatic Transmission (RPOs M30, M32 or M70)
Supercede:
This bulletin is being revised to add the 2009 model year and add details regarding spacer plates.
Please discard Corporate Bulletin Number 01-07-30-036G (Section 07 - Transmission/Transaxle).
Some dealership technicians may have difficulty diagnosing DTC P0756, 2-3 Shift Valve
Performance on 4L60-E, 4L65-E or 4L70E automatic transmissions. As detailed in the Service
Manual, when the PCM detects a 4-3-3-4 shift pattern, DTC P0756 will set. Some customers may
also describe a condition of a second, third or fourth gear start that may have the same causes but
has not set this DTC yet. Below are some tips when diagnosing this DTC:
^ This is a performance code. This means that a mechanical malfunction exists.
^ This code is not set by electrical issues such as a damaged wiring harness or poor electrical
connections. Electrical problems would cause a DTC P0758, P0787 or P0788 to set.
^ The most likely cause is chips/debris plugging the filtered AFL oil at orifice # 29 on the top of the
spacer plate (48). This is a very small hole and is easily plugged by a small amount of debris. It is
important to remove the spacer plate and inspect orifice # 29 and the immediate area for the
presence of chips/debris. Also, the transmission case passage directly above this orifice and the
valve body passage directly below should be inspected and cleaned of any chips/debris. For 2003
and newer vehicles the spacer plate should be replaced. The service replacement spacer plate is a
bonded style with gaskets and solenoid filter screens bonded to the spacer plate. These screens
can help to prevent plugging of orifice # 29 caused by small debris or chips.
^ This code could be set if the 2-3 shift valve (368) were stuck or hung-up in its bore. Inspect the
2-3 shift valve (368) and the 2-3 shuttle valve (369) for free movement or damage and clean the
valves, the bore and the valve body passages.
^ This code could be set by a 2-3 shift solenoid (367b) if it were cracked, broken or leaking. Refer
to Shift Solenoid Leak Test in the appropriate Service Manual for the leak test procedure. Based on
parts return findings, a damaged or leaking shift solenoid is the least likely cause of this condition.
Simply replacing a shift solenoid will not correct this condition unless the solenoid has been found
to be cracked, broken or leaking.
It is important to also refer to the appropriate Service Manual or Service Information (SI) for further
possible causes of this condition.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Channel Plate, A/T >
Component Information > Technical Service Bulletins > Page 7410
Channel Plate: Specifications
4L60-E
Plate to Case Bolt (Shipping)
...............................................................................................................................................
27.0-34.0 Nm (20-25 ft. lbs.) Plate to Converter Bolt (Shipping)
....................................................................................................................................... 27.0-34.0 Nm
(20-25 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Clutch: > 08-07-30-027 > Jun > 08 > A/T - No
Movement in Drive or 3rd Gear
Clutch: Customer Interest A/T - No Movement in Drive or 3rd Gear
TECHNICAL
Bulletin No.: 08-07-30-027
Date: June 04, 2008
Subject: No Movement When Transmission is Shifted to Drive or Third - Normal Operation When
Shifted to Second, First or Reverse (Replace Forward Sprag Assembly)
Models: 1982 - 2005 GM Passenger Cars and Light Duty Trucks 2006 - 2007 Buick Rainier 2006
Cadillac Escalade, Escalade ESV, Escalade EXT 2006 Chevrolet SSR 2006 - 2008 Chevrolet
Avalanche, Colorado, Express, Silverado Classic, Silverado, Suburban, Tahoe, TrailBlazer 2006
GMC Yukon Denali, Yukon Denali XL 2006 - 2008 GMC Canyon, Envoy, Savana, Sierra Classic,
Sierra, Yukon, Yukon XL 2006 Pontiac GTO 2006 - 2007 HUMMER H2 2006 - 2008 HUMMER H3
2006 - 2008 Saab 9-7X
with 4L60, 4L60E, 4L65E or 4L70E Automatic Transmission (RPOs MD8, M30, M32, M33 or M70)
Condition
Some customers may comment that the vehicle has no movement when the transmission is shifted
to DRIVE or THIRD position, but there is normal operation when it is shifted to SECOND, FIRST or
REVERSE position.
Cause
This condition may be caused by a damaged forward sprag assembly (642).
Correction
When inspecting the sprag, it is important to test the sprag for proper operation by holding the outer
race (644) with one hand while rotating the input sun gear (640) with the other hand. The sun gear
should rotate only in the counterclockwise direction with the input sun gear facing upward. If the
sprag rotates in both directions or will not rotate in either direction, the sprag elements should be
inspected by removing one of the sprag assembly retaining rings (643). Refer to SI Unit Repair
section for forward clutch sprag disassembly procedures.
If the sprag is found to be damaged, make repairs to the transmission as necessary. A new forward
roller clutch sprag assembly is now available from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Clutch: > 08-07-30-027 > Jun > 08 > A/T - No
Movement in Drive or 3rd Gear > Page 7419
If clutch debris is found, it is also very important to inspect the Pressure Control (PC) solenoid
valve (377) fluid screens. Clean or replace the PC solenoid (377) as necessary. It is also important
to flush and flow check the transmission oil cooler using J45096. Refer to SI Automatic
Transmission Oil Cooler Flushing and Flow Test for the procedure.
The notches above each sprag must point up as shown when assembled into the outer race.
Bearing Assembly, Input Sun Gear
Snap Ring, Overrun Clutch Hub Retaining
Hub, Overrun Clutch
Wear Plate, Sprag Assembly
Retainer and Race Assembly, Sprag
Forward Sprag Assembly
Retainer Rings, Sprag Assembly
Outer Race, Forward Clutch
Washer, Thrust (Input Carrier to Race)
The following information applies when this sprag is used in 1982-86 transmissions.
The new design sprag can be used on models 1982 through 1986, by replacing the entire
assembly (637 - 644). Individual components are NOT
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Clutch: > 08-07-30-027 > Jun > 08 > A/T - No
Movement in Drive or 3rd Gear > Page 7420
interchangeable.
Important:
The wear plate (640) and input thrust washer (660) are not required with the new sprag. Use of the
thrust washer and wear plate with the new sprag assembly will cause a misbuild (correct end play
cannot be obtained).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Clutch: > 08-07-30-009B > May > 08 > A/T 4T80E, Slips in Gear/L/H Axle Seal Leaks
Clutch: Customer Interest A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Clutch: > 08-07-30-027 > Jun >
08 > A/T - No Movement in Drive or 3rd Gear
Clutch: All Technical Service Bulletins A/T - No Movement in Drive or 3rd Gear
TECHNICAL
Bulletin No.: 08-07-30-027
Date: June 04, 2008
Subject: No Movement When Transmission is Shifted to Drive or Third - Normal Operation When
Shifted to Second, First or Reverse (Replace Forward Sprag Assembly)
Models: 1982 - 2005 GM Passenger Cars and Light Duty Trucks 2006 - 2007 Buick Rainier 2006
Cadillac Escalade, Escalade ESV, Escalade EXT 2006 Chevrolet SSR 2006 - 2008 Chevrolet
Avalanche, Colorado, Express, Silverado Classic, Silverado, Suburban, Tahoe, TrailBlazer 2006
GMC Yukon Denali, Yukon Denali XL 2006 - 2008 GMC Canyon, Envoy, Savana, Sierra Classic,
Sierra, Yukon, Yukon XL 2006 Pontiac GTO 2006 - 2007 HUMMER H2 2006 - 2008 HUMMER H3
2006 - 2008 Saab 9-7X
with 4L60, 4L60E, 4L65E or 4L70E Automatic Transmission (RPOs MD8, M30, M32, M33 or M70)
Condition
Some customers may comment that the vehicle has no movement when the transmission is shifted
to DRIVE or THIRD position, but there is normal operation when it is shifted to SECOND, FIRST or
REVERSE position.
Cause
This condition may be caused by a damaged forward sprag assembly (642).
Correction
When inspecting the sprag, it is important to test the sprag for proper operation by holding the outer
race (644) with one hand while rotating the input sun gear (640) with the other hand. The sun gear
should rotate only in the counterclockwise direction with the input sun gear facing upward. If the
sprag rotates in both directions or will not rotate in either direction, the sprag elements should be
inspected by removing one of the sprag assembly retaining rings (643). Refer to SI Unit Repair
section for forward clutch sprag disassembly procedures.
If the sprag is found to be damaged, make repairs to the transmission as necessary. A new forward
roller clutch sprag assembly is now available from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Clutch: > 08-07-30-027 > Jun >
08 > A/T - No Movement in Drive or 3rd Gear > Page 7430
If clutch debris is found, it is also very important to inspect the Pressure Control (PC) solenoid
valve (377) fluid screens. Clean or replace the PC solenoid (377) as necessary. It is also important
to flush and flow check the transmission oil cooler using J45096. Refer to SI Automatic
Transmission Oil Cooler Flushing and Flow Test for the procedure.
The notches above each sprag must point up as shown when assembled into the outer race.
Bearing Assembly, Input Sun Gear
Snap Ring, Overrun Clutch Hub Retaining
Hub, Overrun Clutch
Wear Plate, Sprag Assembly
Retainer and Race Assembly, Sprag
Forward Sprag Assembly
Retainer Rings, Sprag Assembly
Outer Race, Forward Clutch
Washer, Thrust (Input Carrier to Race)
The following information applies when this sprag is used in 1982-86 transmissions.
The new design sprag can be used on models 1982 through 1986, by replacing the entire
assembly (637 - 644). Individual components are NOT
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Clutch: > 08-07-30-027 > Jun >
08 > A/T - No Movement in Drive or 3rd Gear > Page 7431
interchangeable.
Important:
The wear plate (640) and input thrust washer (660) are not required with the new sprag. Use of the
thrust washer and wear plate with the new sprag assembly will cause a misbuild (correct end play
cannot be obtained).
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Clutch: > 08-07-30-009B > May >
08 > A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
Clutch: All Technical Service Bulletins A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Clutch, A/T >
Component Information > Technical Service Bulletins > Page 7436
Clutch: Specifications
4L80-E
Fourth Clutch Housing .........................................................................................................................
................................................. 23 Nm (17 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Specifications
Automatic Transmission Dipstick - Dipstick Tube: Specifications
4L60-E
Oil Level Indicator Bolt .........................................................................................................................
............................................... 47 Nm (35 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Service and Repair > 4L60-E
Automatic Transmission Dipstick - Dipstick Tube: Service and Repair 4L60-E
Filler Tube and Seal Replacement
Removal Procedure
1. Remove the transmission oil level indicator. 2. Raise the vehicle. Refer to Vehicle Lifting. 3.
Remove the nut securing the oil lever indicator tube to the transmission housing.
4. Place a drain pan under the vehicle. 5. Remove the oil level indicator tube from the transmission
case and seal. 6. Remove the seal from the transmission case.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Service and Repair > 4L60-E > Page 7442
1. Install a new seal into the transmission case. 2. Install the oil level indicator tube into the seal.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the nut securing the oil level indicator tube to the transmission stud.
^ Tighten the nut to 18 Nm (13 ft. lbs.).
4. Fill the transmission to the proper level with DEXRON III III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Service and Repair > 4L60-E > Page 7443
Automatic Transmission Dipstick - Dipstick Tube: Service and Repair 4L80-E
Filler Tube and Seal Replacement
Removal Procedure
1. Remove the oil level indicator from the oil level indicator tube.
2. For the gasoline engine, remove the stud securing the transmission fluid fill tube bracket to the
transmission.
3. For the diesel engine, remove the transmission fluid fill tube bracket and ground wire to the
transmission. 4. Raise the vehicle. Refer to Vehicle Lifting. 5. Remove any dirt from the
transmission where the fluid fill tube enters the transmission case. 6. Place a drain pan under the
transmission. 7. Remove the transmission fluid fill tube from the transmission. Pull the tube upward
from the transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Service and Repair > 4L60-E > Page 7444
8. Remove the transmission fill tube seal.
Installation Procedure
1. Install a new oil level indicator tube seal into the transmission case.
2. Install the oil level indicator tube into the seal.
Notice: Refer to Fastener Notice in Service Precautions.
3. For the gasoline engine, install the stud securing the oil level indicator tube bracket to the
transmission.
^ Tighten the stud to 47 Nm (35 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Automatic
Transmission Dipstick - Dipstick Tube > Component Information > Service and Repair > 4L60-E > Page 7445
4. For the diesel engine, install the bolt and nut that secures the oil level indicator tube bracket and
ground wire to the transmission.
^ Tighten the bolt and the nut to 25 Nm (18 ft. lbs.).
5. Lower the vehicle.
6. Install the oil level indicator. 7. Fill the transmission to the proper level with DEXRON III
transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Drain Plug, A/T >
Component Information > Specifications
Drain Plug: Specifications
4L60-E
Plug Assembly, Automatic Transmission Oil Pan (C/K) ......................................................................
.............................................................................................................. 30-40 Nm (22.1-29.5 ft. lbs.)
4L80-E
Oil Pan Drain Plug ...............................................................................................................................
................................................. 34 Nm (25 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Extension Housing, A/T
> Component Information > Specifications
Extension Housing: Specifications
4L80-E
Extension Housing to Case .................................................................................................................
.................................................. 34 Nm (25 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Extension Housing, A/T
> Component Information > Service and Repair > 4L60-E
Extension Housing: Service and Repair 4L60-E
Transmission Extension Housing Assembly Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Support the transmission with
a transmission jack. 3. Place a drain pan under the vehicle. 4. Remove the propeller shaft. 5.
Remove the transmission mount. 6. Remove the case extension bolts (1). 7. Remove the case
extension (2). 8. Remove and discard the case extension O ring seal (3).
Installation Procedure
1. Install a new case extension O ring seal (3). 2. Install the case extension (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the case extension bolts (1).
^ Tighten the case extension bolts (1) to 45 Nm (33 ft. lbs.).
4. Install the transmission mount. 5. Install the propeller shaft. 6. Remove the drain pan and the
transmission jack. 7. Lower the vehicle. 8. Fill the transmission to the proper level with DEXRON III
transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Extension Housing, A/T
> Component Information > Service and Repair > 4L60-E > Page 7454
Extension Housing: Service and Repair 4L80-E
Transmission Extension Housing Assembly Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Support the transmission with
a transmission jack. 3. Place a drain pan under the vehicle. 4. Remove the propeller shaft. 5.
Remove the transmission support and the transmission mount. 6. Remove the case extension bolts
(3). 7. Remove the case extension (1). 8. Remove and discard the case extension O-ring (2).
Installation Procedure
1. Install a new O-ring (2) to the case extension. 2. Install the case extension (1).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the case extension bolts (3).
^ Tighten the case extension bolts (3) to 34 Nm (25 ft. lbs.).
4. Install the transmission support and the transmission mount. 5. Install the propeller shaft. 6.
Remove the drain pan and the transmission jack. 7. Lower the vehicle. 8. Fill the transmission to
the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Technical Service Bulletins > A/T - DEXRON(R)-VI Fluid Information
Fluid - A/T: Technical Service Bulletins A/T - DEXRON(R)-VI Fluid Information
INFORMATION
Bulletin No.: 04-07-30-037E
Date: April 07, 2011
Subject: Release of DEXRON(R)-VI Automatic Transmission Fluid (ATF)
Models:
2008 and Prior GM Passenger Cars and Light Duty Trucks 2003-2008 HUMMER H2 2006-2008
HUMMER H3 2005-2007 Saturn Relay 2005 and Prior Saturn L-Series 2005-2007 Saturn ION
2005-2008 Saturn VUE with 4T45-E 2005-2008 Saab 9-7X Except 2008 and Prior Chevrolet Aveo,
Equinox Except 2006 and Prior Chevrolet Epica Except 2007 and Prior Chevrolet Optra Except
2008 and Prior Pontiac Torrent, Vibe, Wave Except 2003-2005 Saturn ION with CVT or AF23 Only
Except 1991-2002 Saturn S-Series Except 2008 and Prior Saturn VUE with CVT, AF33 or 5AT
(MJ7/MJ8) Transmission Only Except 2008 Saturn Astra
Attention:
DEXRON(R)-VI Automatic Transmission Fluid (ATF) is the only approved fluid for warranty repairs
for General Motors transmissions/transaxles requiring DEXRON(R)-III and/or prior DEXRON(R)
transmission fluids.
Supercede: This bulletin is being revised to update information. Please discard Corporate Bulletin
Number 04-07-30-037D (Section 07 - Transmission/Transaxle).
MANUAL TRANSMISSIONS / TRANSFER CASES and POWER STEERING
The content of this bulletin does not apply to manual transmissions or transfer cases. Any vehicle
that previously required DEXRON(R)-III for a manual transmission or transfer case should now use
P/N 88861800. This fluid is labeled Manual Transmission and Transfer Case Fluid. Some manual
transmissions and transfer cases require a different fluid. Appropriate references should be
checked when servicing any of these components.
Power Steering Systems should now use P/N 9985010 labeled Power Steering Fluid.
Consult the Parts Catalog, Owner's Manual, or Service Information (SI) for fluid recommendations.
Some of our customers and/or General Motors dealerships/Saturn Retailers may have some
concerns with DEXRON(R)-VI and DEXRON(R)-III Automatic Transmission Fluid (ATF) and
transmission warranty claims. DEXRON(R)-VI is the only approved fluid for warranty repairs for
General Motors transmissions/transaxles requiring DEXRON(R)-III and/or prior DEXRON(R)
transmission fluids (except as noted above). Please remember that the clean oil reservoirs of the
J-45096 - Flushing and Flow Tester machine should be purged of DEXRON(R)-III and filled with
DEXRON(R)-VI for testing, flushing or filling General Motors transmissions/transaxles (except as
noted above).
DEXRON(R)-VI can be used in any proportion in past model vehicles equipped with an automatic
transmission/transaxle in place of DEXRON(R)-III (i.e. topping off the fluid in the event of a repair
or fluid change). DEXRON(R)-VI is also compatible with any former version of DEXRON(R) for use
in automatic transmissions/transaxles.
DEXRON(R)-VI ATF
General Motors Powertrain has upgraded to DEXRON(R)-VI ATF with the start of 2006 vehicle
production.
Current and prior automatic transmission models that had used DEXRON(R)-III must now only use
DEXRON(R)-VI.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Technical Service Bulletins > A/T - DEXRON(R)-VI Fluid Information > Page 7459
All 2006 and future model transmissions that use DEXRON(R)-VI are to be serviced ONLY with
DEXRON(R)-VI fluid.
DEXRON(R)-VI is an improvement over DEXRON(R)-III in the following areas:
* These ATF change intervals remain the same as DEXRON(R)-III for the time being.
2006-2008 Transmission Fill and Cooler Flushing
Some new applications of the 6L80 six speed transmission will require the use of the J 45096 Flushing and Flow Tester to accomplish transmission fluid fill. The clean oil reservoir of the
machine should be purged of DEXRON(R)-III and filled with DEXRON(R)-VI.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Technical Service Bulletins > A/T - DEXRON(R)-VI Fluid Information > Page 7460
Fluid - A/T: Technical Service Bulletins A/T - Water Or Coolant Contamination Information
INFORMATION
Bulletin No.: 08-07-30-035B
Date: November 01, 2010
Subject: Information on Water or Ethylene Glycol in Transmission Fluid
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks with Automatic Transmission
Supercede: This bulletin is being revised to update model years. Please discard Corporate Bulletin
Number 08-07-30-035A (Section 07 - Transmission/Transaxle).
Water or ethylene glycol in automatic transmission fluid (ATF) is harmful to internal transmission
components and will have a negative effect on reliability and durability of these parts. Water or
ethylene glycol in ATF will also change the friction of the clutches, frequently resulting in shudder
during engagement or gear changes, especially during torque converter clutch engagement.
Indications of water in the ATF may include:
- ATF blowing out of the transmission vent tube.
- ATF may appear cloudy or, in cases of extreme contamination, have the appearance of a
strawberry milkshake.
- Visible water in the oil pan.
- A milky white substance inside the pan area.
- Spacer plate gaskets that appear to be glued to the valve body face or case.
- Spacer plate gaskets that appear to be swollen or wrinkled in areas where they are not
compressed.
- Rust on internal transmission iron/steel components.
If water in the ATF has been found and the source of the water entry has not been identified, or if a
leaking in-radiator transmission oil cooler is suspected (with no evidence of cross-contamination in
the coolant recovery reservoir), a simple and quick test kit is available that detects the presence of
ethylene glycol in ATF. The "Gly-Tek" test kit, available from the Nelco Company, should be
obtained and the ATF tested to make an accurate decision on the need for radiator replacement.
This can help to prevent customer comebacks if the in-radiator transmission oil cooler is leaking
and reduce repair expenses by avoiding radiator replacement if the cooler is not leaking. These
test kits can be obtained from:
Nelco Company
Test kits can be ordered by phone or through the website listed above. Orders are shipped
standard delivery time but can be shipped on a next day delivery basis for an extra charge. One
test kit will complete 10 individual fluid sample tests. For vehicles repaired under warranty, the cost
of the complete test kit plus shipping charges should be divided by 10 and submitted on the
warranty claim as a net item.
The transmission should be repaired or replaced based on the normal cost comparison procedure.
Important If water or coolant is found in the transmission, the following components MUST be
replaced.
- Replace all of the rubber-type seals.
- Replace all of the composition-faced clutch plates and/or bands.
- Replace all of the nylon parts.
- Replace the torque converter.
- Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
Important The following steps must be completed when repairing or replacing.
Flush and flow check the transmission oil cooler using J 45096. Refer to Corporate Bulletin Number
02-07-30-052F- Automatic Transmission Oil Cooler Flush and Flow Test Essential Tool J 45096
TransFlow.
- Thoroughly inspect the engine cooling system and hoses and clean/repair as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Technical Service Bulletins > A/T - DEXRON(R)-VI Fluid Information > Page 7461
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Technical Service Bulletins > A/T - DEXRON(R)-VI Fluid Information > Page 7462
Fluid - A/T: Technical Service Bulletins A/T - Oil Cooler Flushing/Flow Check Procedures
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 99-07-30-017A
Date: February, 2003
INFORMATION
Subject: Automatic Transmission Oil Cooler Flushing and Flow Check Procedures
Models: 2003 and Prior GM Light Duty Trucks 2003 HUMMER H2 with Allison(R) Automatic
Transmission (RPO M74)
This bulletin revises bulletin 99-07-30-017 to reflect the release of the new Transflow(R) J 45096
Transmission Cooling System Service Tool. The Transflow(R) Transmission Cooling System
Service Tool is to be used for all vehicles. Please discard Corporate Bulletin Number 99-07-30-017
(Section 07 - Transmission/Transaxle). Refer to Corporate Bulletin Number 02-07-30-052.
Important:
If you were sent here by the instruction booklet for the J 45096 TransFlow(R) machine, note that
the table has been moved to Corporate Bulletin Number 02-07-30-052.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Specifications > Capacity Specifications
Fluid - A/T: Capacity Specifications
Transmission Fluid 4L60-E Pan Removal ...........................................................................................
.......................................................................................................... 4.7L (5.0 Qt) Overhaul ..............
..............................................................................................................................................................
............................ 10.6L (11.0 Qt) 4L80-E Dry ....................................................................................
............................................................................................................................ 12.8L (13.5 Qt) Pan
Removal ..............................................................................................................................................
....................................................... 7.8L (7.7 Qt)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Specifications > Capacity Specifications > Page 7465
Fluid - A/T: Fluid Type Specifications
Transmission Fluid Type
Type .....................................................................................................................................................
...................................... DEXRON III or Equivalent
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E
Fluid - A/T: Service and Repair 4L60-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
Caution: When the transmission is at operating temperatures, take necessary precautions when
removing the drain plug, to avoid being burned by draining field.
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the
transmission oil pan. 3. Remove the oil pan drain plug, if equipped. 4. If necessary, remove the
bolts and position aside the range selector cable bracket for clearance while lowering the pan. It is
not necessary to
remove the cable from the lever or bracket.
5. Remove the oil pan bolts from the front and sides of the pan only. 6. Loosen the rear oil pan
bolts approximately 4 turns. 7. Lightly tap the oil pan with a rubber mallet in order to loosen the pan
to allow the fluid to drain.
8. Remove the remaining oil pan bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E > Page 7468
9. Remove the oil pan and the gasket.
10. Grasp firmly while pulling down with a twisting motion in order to remove the filter.
11. Remove the filter seal. The filter seal may be stuck in the pump; if necessary, carefully use
pliers or another suitable tool to remove the seal. 12. Discard the seal. 13. Inspect the fluid color.
14. Inspect the filter. Pry the metal crimping away from the top of the filter and pull apart. The filter
may contain the following evidence for root cause
diagnosis: ^
Clutch material
^ Bronze slivers indicating bushing wear
^ Steel particles
15. Clean the transmission case and the oil pan gasket surfaces with solvent, and air dry. You must
remove all traces of the old gasket material.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E > Page 7469
1. Coat the new filter seal with automatic transmission fluid. 2. Install the new filter seal into the
transmission case. Tap the seal into place using a suitable size socket. 3. Install the new filter into
the case.
4. Install the oil pan and a new gasket.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan bolts.
^ Tighten the oil pan to transmission case bolts alternately and evenly to 11 Nm (97 inch lbs.).
6. If previously removed, install the range selector cable bracket and bolts.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Apply a small amount of sealant GM P/N 12346004 to the threads of the oil pan drain plug, if
equipped. 8. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E > Page 7470
9. Lower the vehicle.
10. Fill the transmission to the proper level with DEXRON III transmission fluid. 11. Check the
COLD fluid level reading for initial fill only. 12. Inspect the oil pan gasket for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E > Page 7471
Fluid - A/T: Service and Repair 4L80-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the transmission oil pan. 3.
Remove the oil pan drain plug, if equipped. 4. Remove the oil pan bolts. 5. Remove the oil pan. 6.
Remove the gasket. 7. Remove the magnet.
8. Remove the oil filter. 9. Remove the filter neck seal.
10. The transmission oil pan gasket is reusable. Inspect the gasket and replace as needed. 11.
Clean the transmission case and the oil pan gasket surfaces with solvent.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid - A/T >
Component Information > Service and Repair > 4L60-E > Page 7472
1. Install the filter neck seal. 2. Install the oil filter.
3. Install the oil pan gasket to the pan. 4. Install the magnet into the bottom of the pan.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan to the transmission with seventeen bolts.
^ Tighten the oil pan bolts to 11 Nm (97 inch lbs.).
6. Apply a small amount of sealant GM P/N 12346004 to the treads of the drain plug, if equipped.
7. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
8. Lower the vehicle. 9. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E
Fluid Filter - A/T: Service and Repair 4L60-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
Caution: When the transmission is at operating temperatures, take necessary precautions when
removing the drain plug, to avoid being burned by draining field.
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the
transmission oil pan. 3. Remove the oil pan drain plug, if equipped. 4. If necessary, remove the
bolts and position aside the range selector cable bracket for clearance while lowering the pan. It is
not necessary to
remove the cable from the lever or bracket.
5. Remove the oil pan bolts from the front and sides of the pan only. 6. Loosen the rear oil pan
bolts approximately 4 turns. 7. Lightly tap the oil pan with a rubber mallet in order to loosen the pan
to allow the fluid to drain.
8. Remove the remaining oil pan bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E > Page 7477
9. Remove the oil pan and the gasket.
10. Grasp firmly while pulling down with a twisting motion in order to remove the filter.
11. Remove the filter seal. The filter seal may be stuck in the pump; if necessary, carefully use
pliers or another suitable tool to remove the seal. 12. Discard the seal. 13. Inspect the fluid color.
14. Inspect the filter. Pry the metal crimping away from the top of the filter and pull apart. The filter
may contain the following evidence for root cause
diagnosis: ^
Clutch material
^ Bronze slivers indicating bushing wear
^ Steel particles
15. Clean the transmission case and the oil pan gasket surfaces with solvent, and air dry. You must
remove all traces of the old gasket material.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E > Page 7478
1. Coat the new filter seal with automatic transmission fluid. 2. Install the new filter seal into the
transmission case. Tap the seal into place using a suitable size socket. 3. Install the new filter into
the case.
4. Install the oil pan and a new gasket.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan bolts.
^ Tighten the oil pan to transmission case bolts alternately and evenly to 11 Nm (97 inch lbs.).
6. If previously removed, install the range selector cable bracket and bolts.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Apply a small amount of sealant GM P/N 12346004 to the threads of the oil pan drain plug, if
equipped. 8. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E > Page 7479
9. Lower the vehicle.
10. Fill the transmission to the proper level with DEXRON III transmission fluid. 11. Check the
COLD fluid level reading for initial fill only. 12. Inspect the oil pan gasket for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E > Page 7480
Fluid Filter - A/T: Service and Repair 4L80-E
Automatic Transmission Fluid/Filter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the transmission oil pan. 3.
Remove the oil pan drain plug, if equipped. 4. Remove the oil pan bolts. 5. Remove the oil pan. 6.
Remove the gasket. 7. Remove the magnet.
8. Remove the oil filter. 9. Remove the filter neck seal.
10. The transmission oil pan gasket is reusable. Inspect the gasket and replace as needed. 11.
Clean the transmission case and the oil pan gasket surfaces with solvent.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Filter - A/T >
Component Information > Service and Repair > 4L60-E > Page 7481
1. Install the filter neck seal. 2. Install the oil filter.
3. Install the oil pan gasket to the pan. 4. Install the magnet into the bottom of the pan.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the oil pan to the transmission with seventeen bolts.
^ Tighten the oil pan bolts to 11 Nm (97 inch lbs.).
6. Apply a small amount of sealant GM P/N 12346004 to the treads of the drain plug, if equipped.
7. Install the oil pan drain plug, if equipped.
^ Tighten the oil pan drain plug to 18 Nm (13 ft. lbs.).
8. Lower the vehicle. 9. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line Fitting
Fluid Line/Hose: Technical Service Bulletins A/T - Revised Converter Check Valve/Cooler Line
Fitting
INFORMATION
Bulletin No.: 04-07-30-017B
Date: November 25, 2008
Subject: Information on 4T65-E MN7, M15, M76, MN3 Automatic Transmission Case, Cooler
Fitting and Torque Converter Drain Back Check Ball Change
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks
with one of the HYDRA-MATIC(R) Automatic Transmissions shown above.
Supercede:
This bulletin is being revised to update the Parts Information. Please discard Corporate Bulletin
Number 04-07-30-017A (Section 07 - Transmission/Transaxle).
Effective with Julian date 4019 (January 19, 2004), the 4T65E transaxle cases and cooler fittings
have changed and are not interchangeable with past models. The technician may find that when
replacing the inlet or outlet transmission cooler lines, the new lines cannot be connected to the
transmission.
A change to the transmission cooler line fittings was implemented in production on February 1,
2004. The cooler line fittings were changed to a design with a longer lead in pilot (1). The cooler
line fittings with the longer lead in pilot will not fit on models built before February 1, 2004.
The longer lead in pilot fittings (1) (9/16-18 UNF) have replaced the shorter lead in pilot fittings (2)
(3/8-18 NPSF w/check ball & 1/4-18 NPSF).
If the transmission cooler lines will not connect, then replace them with the following cooler line
fittings as appropriate with the older, shorter lead in pilot design:
^ For vehicles built prior to February 1, 2004, use Transmission Fluid Cooler Inlet Hose, P/N
20793004.
^ For vehicles built after February 1, 2004, use Transmission Fluid Cooler Inlet Hose, second
design P/N 15264588.
^ For vehicles built prior to February 1, 2004, use Transmission Fluid Cooler Outlet Hose, P/N
20793005.
^ For vehicles built after February 1, 2004, use Transmission Fluid Cooler Outlet Hose, second
design P/N 15264589.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line Fitting > Page
7486
The torque specification has changed for the fittings to case. The torque has changed from 38 Nm
(28 lb ft) to 32 Nm (23 lb ft).
Tighten
Tighten the new cooler fittings to 32 Nm (23 lb ft).
The converter drain back check ball (420C) has been removed from the cooler line fitting and is
now located in the channel plate.
If you get a concern of no movement in the morning or after sitting for several hours, the cooler
check ball should be inspected.
The best way to determine where the check ball is located is to look at the cooler line fittings. The
old fittings are different sizes (3/8-18 NPSF & 1/4-18 NPSF) and would contain the cooler check
ball. The new fittings are the same size as each other (9/16-18 UNF) and do not have a cooler
check ball.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line Fitting > Page
7487
Fluid Line/Hose: Technical Service Bulletins A/T - Cooler Line Fitting Applications
Bulletin No.: 08-07-30-004
Date: January 31, 2008
INFORMATION
Subject: 4L60-E, 4L65-E, 4L70-E HYDRA-MATIC(R) Automatic Transmission (RPOs M30, M70
M32, M33, MK2 MD6)
Oil Cooler Fitting Change
Models: 1997-2008 GM Light Duty Trucks (Including Saab)
with 4L60-E, 4L65-E, 4L70-E HYDRA-MATIC(R) Automatic Transmission (RPOs M30, M70, M3,
M33, MK2, MD6)
Aluminum cooler line fittings - These new fittings (2) cannot be used on earlier cases because the
threaded hole is not the same size. Old style fittings (1) will continue to be available through SPO
parts.
Service cases will be the new case and fittings. The old cases with the old thread design will not be
maintained for service. The connection on the hose side will accept both the short snout and the
newer longer snout cooler hose assemblies.
The fittings (1) have a new torque specification of 20 N.m (14 lb ft). They also have one inner and
one outer "0" ring that are not serviced separately.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line Fitting > Page
7488
The new thread size 9/16-1a UNF-2A (1) was implemented on 11-29-07 or Julian date 333.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Technical Service Bulletins > Page 7489
Fluid Line/Hose: Specifications
4L60-E
Transmission Oil Cooler Pipe Fitting
................................................................................................................................... 35.0-41.0 Nm
(26-30 ft. lbs.) Cooler Pipe Connector
.........................................................................................................................................................
35.0-41.0 Nm (26-30 ft. lbs.)
4L80-E
Cooler Pipe Connector Nut at Case and Radiator
................................................................................................................................. 38 Nm (28 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E
Fluid Line/Hose: Service and Repair 4L60-E
Transmission Fluid Cooler Hose/Pipe Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Pull the plastic cap back from the quick connect
fitting. 3. Remove the cooling lines from the clips. 4. Remove the two retaining rings securing the
two cooling lines to the transmission.
5. Use a bent tip screwdriver.
6. Pull on the open ends of the retaining ring in order to rotate the retaining ring around the quick
connect fitting until the retaining ring is out of the
fitting. Discard the retaining ring.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7492
7. Pull the cooling line straight out from the quick connect fitting. 8. Repeat this procedure to
remove all the remaining cooling lines from quick connect fittings.
9. If equipped, remove the oil cooling lines from the auxiliary oil cooler.
10. Remove the oil cooling lines from the vehicle.
Installation Procedure
1. Install the transmission oil cooler lines to the vehicle.
Important: ^
Do not reuse any of the existing oil lines or oil line fittings if there is excessive corrosion.
^ Do not reuse any of the existing retaining rings that were removed from the existing quick
connect fittings. All retaining rings being installed must be new.
^ Ensure the following procedures are performed when installing the new retaining rings onto the
fittings.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7493
2. Install a NEW retaining ring (E-clip) into the quick connect fitting using the following procedure:
3. Hook one of the open ends of the retaining ring in one of the slots in the quick connect fitting.
4. Rotate the retaining ring around the fitting until the retaining ring is positioned with all three ears
through the three slots on the fitting.
5. Do not install the new retaining ring onto the fitting by pushing the retaining ring.
6. Ensure that the three retaining ring ears are seen from inside the fitting and that the retaining
ring moves freely in the fitting slots. 7. Install the NEW retaining ring (E-clip) into the remaining
quick connect fittings.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7494
8. Install the cooler line into the quick connect fitting. 9. Insert the cooler line end into the quick
connect fitting until a click is either heard or felt.
10. Do not use the plastic cap on the cooler line in order to install the cooler line into the fitting. 11.
Pull back sharply on the cooler line in order to ensure that the cooler line is fastened into the quick
connect fitting.
12. Position (snap) the plastic cap onto the fitting. Do not manually depress the retaining ring when
installing the plastic cap onto the quick connect
fitting.
13. Ensure that the plastic cap is fully seated against the fitting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7495
14. Ensure that no gap is present between the cap and the fitting.
15. Ensure that the yellow identification band on the tube is hidden within the quick connect fitting.
A hidden yellow identification band indicates
proper joint seating.
16. Do not install the cooler line end into the fining incorrectly. 17. If you cannot position the plastic
cap against the fitting, remove the retaining ring from the quick connect fitting. Check the retaining
ring and the
tube end in order to ensure neither is bent. Replace the cooler line or the retaining ring if
necessary, and reinstall the cooler line per the installation procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7496
18. Install the cooling lines to the transmission. 19. If equipped, install the oil cooling lines to the
auxiliary oil cooler. 20. Install the cooling lines to the clips. 21. Ensure all of the protective plastic
caps are positioned over all of the quick connect fittings. 22. Lower the vehicle. 23. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7497
Fluid Line/Hose: Service and Repair 4L80-E
Transmission Fluid Cooler Hose/Pipe Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Pull the plastic cap back from the quick connect
fitting. 3. Remove the cooling lines from the clips. 4. Remove the two retaining rings securing the
two cooling lines to the transmission.
5. Use a bent tip screwdriver.
6. Pull on the open ends of the retaining ring in order to rotate the retaining ring around the quick
connect fitting until the retaining ring is out of the
fitting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7498
Discard the retaining ring.
7. Pull the cooling line straight out from the quick connect fitting. 8. Repeat this procedure to
remove all the remaining cooling lines from quick connect fittings.
9. If vehicle does not have an auxiliary transmission oil cooler, disconnect the cooling lines from the
radiator.
10. If vehicle is equipped with an auxiliary oil cooler, disconnect the oil cooling lines from the
auxiliary oil cooler.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7499
11. For vehicles equipped with an auxiliary oil cooler, remove the oil cooling lines from the frame
rail.
Installation Procedure
1. Install the transmission oil cooler line to the vehicle.
Important: ^
Do not reuse any of the oil lines or oil line fittings if there is excessive corrosion.
^ Do not reuse any of the existing retaining rings that were removed from the existing quick
connect fittings. All retaining rings being installed must be new.
^ Ensure the following procedures are performed when installing the new retaining rings onto the
fittings.
2. Install a NEW retaining ring (E-clip) into the quick connect fitting using the following procedure:
3. Hook one of the open ends of the retaining ring in one of the slots in the quick connect fitting.
4. Rotate the retaining ring around the fitting until the retaining ring is positioned with all three ears
through the three slots on the fitting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7500
5. Do not install the new retaining ring onto the fitting by pushing the retaining ring.
6. Ensure that the three retaining ring ears are seen from inside the fitting and that the retaining
ring moves freely in the fitting slots. 7. Install a NEW retaining ring (E-clip) into the remaining quick
connect fittings.
8. Install the cooler line into the quick connect fitting. 9. Insert the cooler line end into the quick
connect fitting until a click is either heard or felt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7501
10. Install the cooler lines to the vehicle.
11. Do not use the plastic cap on the cooler line in order to install the cooler line into the fitting. 12.
Pull back sharply, on the cooler line, in order to ensure that the cooler line is fastened into the quick
connect fitting.
13. Position (snap) the plastic cap onto the fitting. Do not manually depress the retaining ring when
installing the plastic cap onto the quick connect
fitting.
14. Ensure that the plastic cap is fully seated against the fitting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7502
15. Ensure that no gap is present between the cap and the fitting.
16. Ensure that the yellow identification band on the tube is hidden within the quick connect fitting.
A hidden yellow identification band indicates
proper joint seating.
17. Do not install the cooler line end into the fitting incorrectly. 18. If you cannot position the plastic
cap against the fitting, remove the retaining ring from the quick connect fitting. Check the retaining
ring and the
tube end in order to ensure neither is bent. Replace the cooler line or the retaining ring if
necessary, and reinstall the cooler line per the installation procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7503
19. For vehicles not equipped with an auxiliary oil cooler, install the cooling lines to the radiator.
20. For vehicles equipped with an auxiliary oil cooler, install the oil cooling lines to the auxiliary oil
cooler.
21. For vehicles equipped with an auxiliary oil cooler, install the oil cooling lines to the frame rail.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Line/Hose, A/T >
Component Information > Service and Repair > 4L60-E > Page 7504
22. Install the cooling lines to the transmission. 23. Install the cooling lines to the clips. 24. Ensure
all of the protective plastic caps are positioned over all of the quick connect fittings. 25. Lower the
vehicle. 26. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pan, A/T >
Component Information > Specifications
Fluid Pan: Specifications
4L60-E
Oil Pan to Transmission Case Bolt
.................................................................................................................................................... 11
Nm (97 inch lbs.) Transmission Oil Pan to Case Bolt
.......................................................................................................................................... 9.5-13.8
Nm (7-10 ft. lbs.)
4L80-E
Oil Pan to Case ...................................................................................................................................
.................................................. 24 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pressure
Sensor/Switch, A/T > Component Information > Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pressure
Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pressure
Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E > Page 7513
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pressure
Sensor/Switch, A/T > Component Information > Diagrams > Page 7514
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service
Fluid Pump: Technical Service Bulletins A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service
Bulletin No.: 04-07-30-023
Date: May 12, 2004
INFORMATION
Subject: Oil Pump Assembly Seal and Transmission Case Change
Models: 2002-2004 Cars and Light Duty Trucks with 4L60-E or 4L65-E Automatic Transmissions
(RPOs M30, M32 or M33)
An improved oil pump to case seal design has been made to the 4L60-E/4L65-E transmission. The
new design affects the oil pump, the oil pump seal, the transmission pan bolts and the transmission
case. The complete design was implemented in three phases.
The first phase, beginning in September 2002, relocated the machining of the oil pump 0-ring seal
groove in the pump body. The 0-ring seal groove moved 1.6 mm (0.62 in) inward on the pump body
in order to place the sealing surface deeper into the case bore. The relocated pump body groove
can be identified by measuring the groove location. Pump bodies that measure 2.3 mm (0.09 in)
from the machined surface to the groove opening have the relocated 0-ring seal groove. Pump
bodies that measure 3.9 mm (0.15 in) are prior to September 2002 design.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7519
The first phase also machined a case chamfer leading into the pump bore (2). The chamfer is
designed to help eliminate possible 0-ring seal damage during pump installation.
Phase two modified the case casting and the chamfer into the pump bore. The casting change left
additional material in the surrounding pump bore to allow deeper bore machining in order to create
the necessary sealing surface for a new pump seal design. The leading surface into the pump bore
was also machined with a modified chamfer (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7520
Phase three will eliminate the oil pump body 0-ring seal groove and the 0-ring seal. Beginning
March 2004, a new stamped carrier molded rubber seal (2) will be used to seal the pump assembly
to the transmission case.
The pump sealing surface is now the outer diameter of the pump and the inner diameter (1) of the
transmission case bore. Unlike the current 0-ring seal, which is installed on the oil pump body, the
new seal is installed after the pump assembly is properly positioned and torqued in place. Seating
the seal is accomplished when the torque converter housing is installed, which presses the seal (3)
into position between the pump and the case bore (1).
As a result of the modified casting and the deeper pump bore machining, the area between the oil
pan mounting surface and the pump bore has decreased. Because of the reduced material in this
area (1) it is necessary to use the shorter oil pan attaching bolts (2). Early pan bolts (3), before
November 2002, should not be used with the modified case design, since they are 1.0 mm (0.39 in)
longer and could deform the chamfer surface (4).
Service Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7521
When Servicing transmissions with the new seal design, use the following precautions:
^ The outer diameter of the pump assembly and case bore must be clean and free of burrs or
raised surfaces. Be aware of sharp edges that could damage the seal during installation.
^ The seal should be clean and dry before installation. It does not require lubrication for installation.
^ The seal should be inspected prior to installation for obvious damage.
^ It is preferable to hand-start the seal positioning the seal evenly around the case bore before
installing the torque converter housing.
^ The seal can be easily removed by prying it out, typical of a pressed-on seal.
^ The seal may be reused, however a thorough inspection must be performed. Inspect the seal for
the following conditions:
^ Distortion of the metal carrier or separation from the rubber seal.
^ A cut, deformed, or damaged seal.
^ Refer to the appropriate unit repair information in SI for seal removal and installation procedures.
Parts Interchangeability Information
In order to properly service the different designs, it is necessary to correctly identify and select
corresponding parts for each level. This table provides a summary of the part usage for the
different design levels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7522
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7523
Fluid Pump: Technical Service Bulletins A/T - 4L65E, 4L60E, 4L60, 200-4R Oil Pump Spring
Bulletin No.: 04-07-30-006
Date: February 11, 2004
INFORMATION
Subject: 4L65-E, 4L60-E, 4L60 and 200-4R Automatic Transmission Oil Pump Spring First and
Second Design Identification
Models: 2004 and Prior Passenger Cars and Light Duty Trucks 2003-2004 HUMMER H2
with 4L65-E, 4L60-E, 4L60 or 200-4R Automatic Transmission
The purpose of this bulletin is to identify the oil pump spring usage for the two different pump
designs. Manufacturing of the first design oil pump springs ended December 15, 2003.
Manufacturing of the second design oil pump spring began December 16, 2003
The first design oil pump springs (206) and (207) DO NOT have any identification markings. The
first design springs (206) and (207) use an inner and outer spring, two springs.
The second design oil pump spring (245) is identified with tapered ends on the spring (245) as
shown above. The second design spring (245) is a single spring.
When servicing either (first design or second design) oil pump body, use the new single oil pump
spring (245) with tapered ends.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7524
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7525
Fluid Pump: Technical Service Bulletins A/T - 4L60-E Oil Pump Identification
Bulletin No.: 03-07-30-056
Date: November 05, 2003
INFORMATION
Subject: 4L60-E Automatic Transmission Oil Pump First And Second Design Identification
Models: 1997-2002 Chevrolet Camaro 1997-2002 Pontiac Firebird 2002-2004 Cadillac Escalade,
Escalade EXT 1997-1999 Chevrolet C/K Full Size Pickup 1997-2004 Chevrolet Astro, Blazer,
Corvette, Express, S-10, Suburban 1999-2004 Chevrolet Silverado 2000-2004 Chevrolet Tahoe
2002-2004 Chevrolet Avalanche, TrailBlazer 2004 Chevrolet Colorado, SSR 1997-1999 GMC
Suburban 1997-2001 GMC Jimmy 1997-2004 GMC Envoy, Safari, Savana, Sierra, Sonoma
1999-2004 GMC Denali 2000-2004 GMC Yukon, Yukon XL 2004 GMC Canyon 1997-2004
Oldsmobile Bravada 2003-2004 HUMMER H2 with 4L60-E Automatic Transmission (RPOs M30,
M32, M33)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7526
The purpose of this bulletin is to identify the correct oil pump rotor (212) and slide (203) usage for
the two different transmission oil pump designs.
Manufacturing of the first design oil pump rotor (212) and slide (203) ended November 30, 2000.
Manufacturing of the second design oil pump rotor (212) and slide (203) began December 1, 2000.
Important:
It is critical that the first and second design oil pump rotors and slides do not become intermixed.
Do not use first design pump components with second design pump components. If the pump
components from either design are intermixed, pump efficiency will be affected resulting in less
than optimal pump performance.
The first design oil pump rotor (212) and slide (203) DO NOT have any identification markings.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7527
The second design oil pump rotor (212) and slide (203) are identified with dimples (circular
depression) as shown above.
The rotor (212) has two dimples adjacent to the rotor drive tangs (1).
The slide (203) has one dimple located on the spring tab (2).
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Fluid Pump, A/T >
Component Information > Technical Service Bulletins > Page 7528
Fluid Pump: Specifications
4L60-E
Pump Assembly to Case Bolt
...............................................................................................................................................
26.0-32.0 Nm (19-24 ft. lbs.) Pump Cover to Pump Body Bolt
.......................................................................................................................................... 20.0-27.0
Nm (15-20 ft. lbs.)
4L80-E
Pump Assembly to Case .....................................................................................................................
.................................................. 24 Nm (18 ft. lbs.) Pump Body to Cover ...........................................
................................................................................................................................. 24 Nm (18 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Lamps and Indicators A/T > Shift Indicator > Component Information > Description and Operation
Shift Indicator: Description and Operation
The IPC displays the vehicle speed based on the vehicle speed signal from the PCM. The PCM
converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The IPC uses the
vehicle speed signal circuit from the PCM in order to calculate the vehicle speed. The speedometer
defaults to 0 km/h (0 mph) if a malfunction in the vehicle speed signal circuit exists.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Output Shaft, A/T >
Component Information > Technical Service Bulletins > A/T - 2-3 Upshift or 3-2 Downshift Clunk Noise
Output Shaft: Technical Service Bulletins A/T - 2-3 Upshift or 3-2 Downshift Clunk Noise
INFORMATION
Bulletin No.: 01-07-30-042F
Date: February 05, 2010
Subject: Information on 2-3 Upshift or 3-2 Downshift Clunk Noise
Models:
2010 and Prior GM Passenger Cars and Light Duty Trucks 2010 and Prior HUMMER H2, H3
2005-2009 Saab 9-7X with 4L60-E, 4L65-E or 4L70-E Automatic Transmission (RPOs M30, M32,
M70)
Supercede: This bulletin is being revised to add the 2010 model year and 4L70E transmission.
Please discard Corporate Bulletin Number 01-07-30-042E (Section 07 - Transmission/Transaxle).
Important For 2005 model year fullsize utilities and pickups, refer to Corporate Bulletin
05-07-30-012.
Some vehicles may exhibit a clunk noise that can be heard on a 2-3 upshift or a 3-2 downshift.
During a 2-3 upshift, the 2-4 band is released and the 3-4 clutch is applied. The timing of this shift
can cause a momentary torque reversal of the output shaft that results in a clunk noise. This same
torque reversal can also occur on a 3-2 downshift when the 3-4 clutch is released and the 2-4 band
applied. This condition may be worse on a 4-wheel drive vehicle due to the additional tolerances in
the transfer case.
This is a normal condition. No repairs should be attempted.
Disclaimer
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Parking Pawl, A/T >
Component Information > Specifications
Parking Pawl: Specifications
4L80-E
Parking Pawl Bracket to Case .............................................................................................................
.................................................. 24 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Parking Pawl, A/T >
Component Information > Specifications > Page 7540
Parking Pawl: Service and Repair
Park Lock Pawl and Actuator Replacement (4L80-E)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the oil pan and filter. 3. Remove the
park/neutral position switch. 4. Remove the manual shaft nut and the pin. 5. Remove the detent
lever and the actuator assembly. 6. Remove the bolts and the parking pawl bracket. 7. Remove the
parking pawl return spring.
8. Use the modified screw extractor in order to remove the plug. 9. Remove the parking pawl shaft
retainer, the shaft and the pawl.
Important: If the manual shaft binds in the case during removal, file or sand the shaft in the area
adjacent to the detent lever.
10. Remove the manual shaft. 11. Remove the manual shaft seal.
Installation Procedure
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Parking Pawl, A/T >
Component Information > Specifications > Page 7541
1. Install the pawl shaft. 2. Install the parking pawl. 3. Install the plug using a 8 mm or (5/16 inch)
rod with Loctite or the equivalent. 4. Install the retainer.
5. Install the pawl return spring. 6. Install the detent lever to the actuator assembly. 7. Install
actuator assembly over the parking pawl. 8. Install the manual shaft seal. 9. Lubricate the manual
shaft with transmission oil and install the manual shaft into the case.
10. install the nut on the shaft. 11. Install the roll pin.
Notice: Refer to Fastener Notice in Service Precautions.
12. Install the parking lock bracket with the two bolts.
^ Tighten the bolts to 24 Nm (18 ft. lbs.).
13. Install the park/neutral position switch. 14. Install the oil pan and filter. 15. Lower the vehicle.
16. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Specifications
Pressure Regulating Solenoid: Specifications
4L60-E
Pressure Control Solenoid Bracket to Valve Body Bolt .......................................................................
.......................................................................................................... 8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Pressure Control Solenoid Bracket to Valve Body ..............................................................................
...................................................................................................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Diagrams > 4L60-E
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7547
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Service and Repair > 4L60-E
Pressure Regulating Solenoid: Service and Repair 4L60-E
Pressure Regulator Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
filter. 3. Compress the reverse boost valve sleeve into the bore of the oil pump to release tension
on the reverse boost valve retaining ring. 4. Remove the reverse boost valve retaining ring, then
slowly release tension on the reverse boost valve sleeve.
5. Remove the reverse boost valve sleeve (5) and the reverse boost valve (4). 6. Remove the
pressure regulator isolator spring (3) and the pressure regulator valve spring (2). 7. Remove the
pressure regulator valve (1).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7550
1. Install the pressure regulator valve (1). 2. Install the pressure regulator isolator spring (3) and the
pressure regulator valve spring (2). 3. Install the reverse boost valve (4) in the reverse boost valve
sleeve (5). 4. Install the reverse boost valve (4) and sleeve (5) in the oil pump cover.
5. Compress the reverse boost valve sleeve into the bore of the oil pump to expose the retaining
ring slot. 6. Install the reverse boost valve retaining ring, then slowly release tension on the reverse
boost valve sleeve. 7. Install the transmission oil filter and pan. 8. Lower the vehicle. 9. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7551
Pressure Regulating Solenoid: Service and Repair 4L80-E
Pressure Regulator Replacement
^ Tools Required J 36850 Transjel
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the reverse boost valve bushing retainer ring (2).
4. Remove the following from the reverse boost valve cylinder:
^ The reverse boost valve bushing
^ The reverse boost valve
^ The pressure regulator spring retainer
^ The pressure regulator spring
^ The pressure regulator valve
^ The reverse boost valve bushing
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Pressure Regulating
Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7552
1. Install the pressure regulator valve with J 36850. 2. Pre-assemble the following parts:
^ The reverse boost valve bushing
^ A new reverse boost valve
^ A new pressure regulator spring retainer
^ The added isolator pressure regulator spring
^ The pressure regulator spring
3. Install the pre-assembled parts into the pump bore.
4. Install the reverse boost valve bushing retainer ring while holding the reverse boost valve
bushing in place.
Ensure the retainer ring (2) is in the groove.
5. Install the transmission oil pan and the oil filter. 6. Lower the vehicle. 7. Fill the transmission to
the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > Customer Interest: > 01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid
Leaking From A/T Vent
Seals and Gaskets: Customer Interest A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > Customer Interest: > 01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid
Leaking From A/T Vent > Page 7561
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: >
01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid Leaking From A/T Vent
Seals and Gaskets: All Technical Service Bulletins A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: >
01-07-30-032E > Sep > 08 > A/T - 4T65E Fluid Leaking From A/T Vent > Page 7567
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > 04-07-30-023
> May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service
Seals and Gaskets: All Technical Service Bulletins A/T - 4L60-E/4L65-E New
Pump/Seal/Case/Service
Bulletin No.: 04-07-30-023
Date: May 12, 2004
INFORMATION
Subject: Oil Pump Assembly Seal and Transmission Case Change
Models: 2002-2004 Cars and Light Duty Trucks with 4L60-E or 4L65-E Automatic Transmissions
(RPOs M30, M32 or M33)
An improved oil pump to case seal design has been made to the 4L60-E/4L65-E transmission. The
new design affects the oil pump, the oil pump seal, the transmission pan bolts and the transmission
case. The complete design was implemented in three phases.
The first phase, beginning in September 2002, relocated the machining of the oil pump 0-ring seal
groove in the pump body. The 0-ring seal groove moved 1.6 mm (0.62 in) inward on the pump body
in order to place the sealing surface deeper into the case bore. The relocated pump body groove
can be identified by measuring the groove location. Pump bodies that measure 2.3 mm (0.09 in)
from the machined surface to the groove opening have the relocated 0-ring seal groove. Pump
bodies that measure 3.9 mm (0.15 in) are prior to September 2002 design.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > 04-07-30-023
> May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7572
The first phase also machined a case chamfer leading into the pump bore (2). The chamfer is
designed to help eliminate possible 0-ring seal damage during pump installation.
Phase two modified the case casting and the chamfer into the pump bore. The casting change left
additional material in the surrounding pump bore to allow deeper bore machining in order to create
the necessary sealing surface for a new pump seal design. The leading surface into the pump bore
was also machined with a modified chamfer (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > 04-07-30-023
> May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7573
Phase three will eliminate the oil pump body 0-ring seal groove and the 0-ring seal. Beginning
March 2004, a new stamped carrier molded rubber seal (2) will be used to seal the pump assembly
to the transmission case.
The pump sealing surface is now the outer diameter of the pump and the inner diameter (1) of the
transmission case bore. Unlike the current 0-ring seal, which is installed on the oil pump body, the
new seal is installed after the pump assembly is properly positioned and torqued in place. Seating
the seal is accomplished when the torque converter housing is installed, which presses the seal (3)
into position between the pump and the case bore (1).
As a result of the modified casting and the deeper pump bore machining, the area between the oil
pan mounting surface and the pump bore has decreased. Because of the reduced material in this
area (1) it is necessary to use the shorter oil pan attaching bolts (2). Early pan bolts (3), before
November 2002, should not be used with the modified case design, since they are 1.0 mm (0.39 in)
longer and could deform the chamfer surface (4).
Service Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > 04-07-30-023
> May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7574
When Servicing transmissions with the new seal design, use the following precautions:
^ The outer diameter of the pump assembly and case bore must be clean and free of burrs or
raised surfaces. Be aware of sharp edges that could damage the seal during installation.
^ The seal should be clean and dry before installation. It does not require lubrication for installation.
^ The seal should be inspected prior to installation for obvious damage.
^ It is preferable to hand-start the seal positioning the seal evenly around the case bore before
installing the torque converter housing.
^ The seal can be easily removed by prying it out, typical of a pressed-on seal.
^ The seal may be reused, however a thorough inspection must be performed. Inspect the seal for
the following conditions:
^ Distortion of the metal carrier or separation from the rubber seal.
^ A cut, deformed, or damaged seal.
^ Refer to the appropriate unit repair information in SI for seal removal and installation procedures.
Parts Interchangeability Information
In order to properly service the different designs, it is necessary to correctly identify and select
corresponding parts for each level. This table provides a summary of the part usage for the
different design levels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > 04-07-30-023
> May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7575
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > 04-07-30-023 >
May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service
Seals and Gaskets: All Technical Service Bulletins A/T - 4L60-E/4L65-E New
Pump/Seal/Case/Service
Bulletin No.: 04-07-30-023
Date: May 12, 2004
INFORMATION
Subject: Oil Pump Assembly Seal and Transmission Case Change
Models: 2002-2004 Cars and Light Duty Trucks with 4L60-E or 4L65-E Automatic Transmissions
(RPOs M30, M32 or M33)
An improved oil pump to case seal design has been made to the 4L60-E/4L65-E transmission. The
new design affects the oil pump, the oil pump seal, the transmission pan bolts and the transmission
case. The complete design was implemented in three phases.
The first phase, beginning in September 2002, relocated the machining of the oil pump 0-ring seal
groove in the pump body. The 0-ring seal groove moved 1.6 mm (0.62 in) inward on the pump body
in order to place the sealing surface deeper into the case bore. The relocated pump body groove
can be identified by measuring the groove location. Pump bodies that measure 2.3 mm (0.09 in)
from the machined surface to the groove opening have the relocated 0-ring seal groove. Pump
bodies that measure 3.9 mm (0.15 in) are prior to September 2002 design.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > 04-07-30-023 >
May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7581
The first phase also machined a case chamfer leading into the pump bore (2). The chamfer is
designed to help eliminate possible 0-ring seal damage during pump installation.
Phase two modified the case casting and the chamfer into the pump bore. The casting change left
additional material in the surrounding pump bore to allow deeper bore machining in order to create
the necessary sealing surface for a new pump seal design. The leading surface into the pump bore
was also machined with a modified chamfer (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > 04-07-30-023 >
May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7582
Phase three will eliminate the oil pump body 0-ring seal groove and the 0-ring seal. Beginning
March 2004, a new stamped carrier molded rubber seal (2) will be used to seal the pump assembly
to the transmission case.
The pump sealing surface is now the outer diameter of the pump and the inner diameter (1) of the
transmission case bore. Unlike the current 0-ring seal, which is installed on the oil pump body, the
new seal is installed after the pump assembly is properly positioned and torqued in place. Seating
the seal is accomplished when the torque converter housing is installed, which presses the seal (3)
into position between the pump and the case bore (1).
As a result of the modified casting and the deeper pump bore machining, the area between the oil
pan mounting surface and the pump bore has decreased. Because of the reduced material in this
area (1) it is necessary to use the shorter oil pan attaching bolts (2). Early pan bolts (3), before
November 2002, should not be used with the modified case design, since they are 1.0 mm (0.39 in)
longer and could deform the chamfer surface (4).
Service Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > 04-07-30-023 >
May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7583
When Servicing transmissions with the new seal design, use the following precautions:
^ The outer diameter of the pump assembly and case bore must be clean and free of burrs or
raised surfaces. Be aware of sharp edges that could damage the seal during installation.
^ The seal should be clean and dry before installation. It does not require lubrication for installation.
^ The seal should be inspected prior to installation for obvious damage.
^ It is preferable to hand-start the seal positioning the seal evenly around the case bore before
installing the torque converter housing.
^ The seal can be easily removed by prying it out, typical of a pressed-on seal.
^ The seal may be reused, however a thorough inspection must be performed. Inspect the seal for
the following conditions:
^ Distortion of the metal carrier or separation from the rubber seal.
^ A cut, deformed, or damaged seal.
^ Refer to the appropriate unit repair information in SI for seal removal and installation procedures.
Parts Interchangeability Information
In order to properly service the different designs, it is necessary to correctly identify and select
corresponding parts for each level. This table provides a summary of the part usage for the
different design levels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > 04-07-30-023 >
May > 04 > A/T - 4L60-E/4L65-E New Pump/Seal/Case/Service > Page 7584
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > Page 7585
Seals and Gaskets: By Symptom
Technical Service Bulletin # 01-07-30-032E Date: 080929
A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > Page 7586
For vehicles repaired under warranty, use the table.
Disclaimer
Technical Service Bulletin # 01-07-30-032E Date: 080929
A/T - 4T65E Fluid Leaking From A/T Vent
TECHNICAL
Bulletin No.: 01-07-30-032E
Date: September 29, 2008
Subject: Transmission Oil Leaking From Transmission Vent (Replace Transmission Case Cover
(Channel Plate) Gasket)
Models: 1997-2009 GM Passenger Cars and Light Duty Trucks (including Saturn)
with Hydra-Matic 4T65-E Automatic Transmission (RPOs MN3, MN7, M15, M76)
Supercede:
This bulletin is being revised to add the 2008 and 2009 model years. Please discard Corporate
Bulletin Number 01-07-30-032D (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak.
Cause
This condition may be caused by an improperly torqued channel plate gasket.
Correction
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Technical Service Bulletins > All Other Service Bulletins for Seals and Gaskets: > Page 7587
To correct this condition, replace the case cover (channel plate) gaskets (429 and 430). Refer to
Unit Repair publication in SI of the appropriate vehicle being serviced.
Visual inspection of the upper gasket (1) will reveal damage at the referenced area.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Service and Repair > 4L60-E
Seals and Gaskets: Service and Repair 4L60-E
Manual Shift Shaft Seal Replacement
Manual Shift Shaft Seal Replacement
^ Tools Required J 43911 Selector Shaft Seal Remover
- J 43909 Selector Shaft Seal installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the Park/Neutral Position (PNP) Switch. 3.
Be sure that the jackscrew for J43911 is backed off and will not interfere with installation of the
removal tool. Slide the seal remover tool over the
selector shaft (2) with the threaded end of the tool towards the seal.
4. Rotate the removal tool so that the threads on the end of the tool engage the steel shell (1) of
the seal. Use a wrench to be sure that the removal tool
is firmly attached to the seal shell.
5. Rotate the jackscrew in the clockwise direction to remove the seal from the bore. Discard the
seal that was removed.
Installation Procedure
1. Carefully slide a new selector shaft seal (1) over the selector shaft (2) with the wide face of the
steel case facing outward. Position the seal so that
it is starting to enter the seal bore.
2. Obtain J 43909 and remove the inner sleeve so that the tool will slide over the selector shaft. 3.
Slide the J 43909 into position so that the end of the tool contacts the seal being installed. Use a
mallet to strike the J 43909 and drive the new seal
into the seal bore until it is seated at the bottom of the bore.
4. Install the PNP Switch. 5. Lower the vehicle. 6. Fill the transmission to the proper level with
DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Transmission Extension Housing Rear Oil Seal Replacement
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Service and Repair > 4L60-E > Page 7590
Transmission Extension Housing Rear Oil Seal Replacement
^ Tools Required J 21426 Extension Housing Seal Installer
- J 36850 Transmission Assembly Lubricant
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the vehicle. 3. Remove the
propeller shaft. 4. Remove the case extension housing rear oil seal. Use a flat bladed tool and
carefully pry the seal from the housing. 5. Inspect the case extension housing for damage. Replace
the extension housing if necessary.
Installation Procedure
1. Lubricate the inside diameter of the new seal with J 36850. 2. Use the J 21426 with a soft faced
mallet to install the seal. 3. Install the seal to the extension housing. 4. Install the propeller shaft. 5.
Remove the drain pan and lower the vehicle. 6. Fill the transmission to the proper level with
DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Service and Repair > 4L60-E > Page 7591
Seals and Gaskets: Service and Repair 4L80-E
Manual Shift Shaft Seal Replacement
Manual Shift Shaft Seal Replacement
^ Tools Required J 43911 Selector Shaft Seal Remover
- J 43909 Selector Shaft Seal Installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the Park/Neutral Position (PNP) Switch. 3.
Be sure that the jackscrew for J 43911 is backed off and will not interfere with installation of the
removal tool. Slide the seal remover tool over the
selector shaft (2) with the threaded end of the tool towards the seal.
4. Rotate the removal tool so that the threads on the end of the tool engage the steel shell (1) of
the seal. Use a wrench to be sure that the removal tool
is firmly attached to the seal shell.
5. Rotate the jackscrew in the clockwise direction to remove the seal from the bore. Discard the
seal that was removed.
Installation Procedure
1. Carefully slide a new selector shaft seal (1) over the selector shaft (2) with the wide face of the
steel case facing outward. Position the seal so that
it is starting to enter the seal bore.
2. Obtain J 43909 and remove the inner sleeve so that the tool will slide over the selector shaft. 3.
Slide the J 43909 into position so that the end of the tool contacts the seal being installed. Use a
mallet to strike the J 43909 and drive the new seal
into the seal bore until it is seated at the bottom of the bore.
4. Install the PNP Switch. 5. Lower the vehicle. 6. Fill the transmission to the proper level with
DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Transmission Extension Housing Rear Oil Seal Replacement
Transmission Extension Housing Rear Oil Seal Replacement
^ Tools Required J 41505 Output Shaft Seal Installer
- J 6125-1B Slide Hammer
- J 23129 Universal Seal Remover
- J 36850 Transmission Assembly Lubricant
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Seals and Gaskets, A/T
> System Information > Service and Repair > 4L60-E > Page 7592
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Place a drain pan under the vehicle. 3. Remove the
propeller shaft. 4. Using the J 6125-1B (1) and the J23129 (2), remove the output shaft seal (3)
from the extension housing (4). 5. Inspect the case extension housing for damage. Replace the
extension housing if necessary.
Installation Procedure
1. Lubricate the inside diameter of the new seal with J 36850. 2. Use the J 41505 (1) with a soft
faced mallet to install the seal (2). 3. Install the seal (2) to the extension housing (3). 4. Install the
propeller shaft. 5. Remove the drain pan and lower the vehicle. 6. Fill the transmission to the
proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E > Page 7599
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > Page 7600
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission > Page 7605
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission > Page 7606
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission > Page 7607
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission > Page 7608
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E
Transmission > Page 7609
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 7615
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E > Page 7618
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7621
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7622
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7623
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 7629
Transmission Speed Sensor: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7632
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7633
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sensors and Switches A/T > Transmission Temperature Sensor/Switch, A/T > Component Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Interlock, A/T >
Shift Interlock Solenoid > Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Interlock, A/T >
Shift Interlock Solenoid > Component Information > Diagrams > Page 7641
Shift Interlock Solenoid: Service and Repair
Automatic Transmission Shift Lock Actuator Replacement
Removal Procedure
Caution: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the body control module bracket. 3. Put the shift lever clevis
into the neutral position. 4. Disconnect the electrical connector. 5. Use a small screwdriver to pry
the automatic transmission shift lock control actuator away from the steering column jacket
assembly and the cable
shift cam assembly.
6. Remove the automatic transmission shift lock control actuator.
Installation Procedure
1. Firmly install the automatic transmission shift lock control actuator onto the steering column
jacket assembly and the cable shift cam assembly. 2. Connect the electrical connector
3. Adjust the automatic transmission shift lock control actuator (with the shift lever clevis in the
neutral position) in the following way:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Interlock, A/T >
Shift Interlock Solenoid > Component Information > Diagrams > Page 7642
3.1. Pull out the tab (1) on the adjuster block side (2) of the automatic transmission shift lock
control actuator.
3.2. Press on the adjuster block (2) to compress the internal adjuster spring, which disengages the
adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible.
3.3. Lock the adjuster block (2) in place by pushing in on the tab (1).
4. Inspect the automatic transmission shift lock control actuator for the following items:
4.1. The automatic transmission shift lock control actuator must lock the shift lever clevis when the
shift lever clevis is put into the park position.
4.2. Depress the brake pedal to move the shift lever out of the park position.
4.3. The actuator will be energized.
4.4. Readjust the automatic transmission shift lock control actuator if needed.
5. Install the body control module bracket. 6. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Specifications
Shift Solenoid: Specifications
4L80-E
Solenoid to Valve Body .......................................................................................................................
............................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > 4L60-E
Shift Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > 4L60-E > Page 7648
Shift Solenoid: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > Page 7649
Shift Solenoid: Service and Repair
Control and Shift Solenoids Replacement
Removal Procedure
1. Remove the transmission oil pan and filter.
Important: Do not remove the valve body for the following procedures. Removal of the 1-2
accumulator is necessary only if servicing the pressure control solenoid.
2. Remove the 1-2 accumulator if necessary. 3. Disconnect the internal wiring harness electrical
connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
4. Remove the pressure control solenoid retainer. 5. Remove the pressure control solenoid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > Page 7650
6. Remove the 1-2 and 2-3 shift solenoid retainers. 7. Remove the 1-2 and 2-3 shift solenoids.
8. Remove the 3-2 control solenoid retainer. 9. Remove the 3-2 control solenoid.
Installation Procedure
1. Install the 3-2 control solenoid. 2. Install the 3-2 control solenoid retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > Page 7651
3. Install the 1-2 and 2-3 shift solenoids. 4. Install the 1-2 and 2-3 shift solenoid retainers.
5. Install the pressure control solenoid. Ensure that the electrical tabs are facing outboard.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
7. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
8. Install the 1-2 accumulator. 9. Install the transmission oil pan and filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Solenoid, A/T >
Component Information > Diagrams > Page 7652
10. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shifter A/T >
Component Information > Specifications
Shifter A/T: Specifications
4L60-E
Floor shift Control Bolt .........................................................................................................................
............................................ 10 Nm (89 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Technical Service Bulletins > A/T - Slipping/Missed Shifts Diagnostic Tips
Shift Cable: Technical Service Bulletins A/T - Slipping/Missed Shifts Diagnostic Tips
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 01-07-30-043
Date: December, 2001
INFORMATION
Subject: Diagnostic Tips for Slipping or Missing Second, Third and/or Fourth Gear
Models: 2001-2002 Chevrolet Camaro, Corvette 2001-2002 Pontiac Firebird 2001-2002 Chevrolet
and GMC C/K Pickup and Utility Models (Silverado, Sierra, Suburban, Tahoe, Yukon, Yukon XL)
2001-2002 Chevrolet and GMC G-Van Models (Express, Savana) 2001-2002 Chevrolet and GMC
M/L-Van Models (Astro, Safari) 2001-2002 Chevrolet and GMC S/T Pickup and Utility Models (S10,
Sonoma, Blazer, Jimmy) 2002 Chevrolet and GMC S/T Utility Models (New Style) (TrailBlazer,
Envoy) 2002 Cadillac Escalade 2001-2002 Oldsmobile Bravada
Recently, a study was completed to determine the causes of slipping/missing 2nd, 3rd or 4th gear
in the 4L60/4L65-E transmission family. This study was conducted using transmissions which were
determined by dealership technicians as having a slipping/missing shift. The transmissions used
were from vehicles with less than 19,000 km (12,000 mi) and the slipping/missing shift condition
was verified during a test drive by dealership personnel before the transmission was removed from
the vehicle. Eight items were found to cause the majority of the slipping/missing shift concerns.
These eight items are listed below in the order of frequency that they were found.
^ Chips in the servo feed oil passage, orifice # 7 in the spacer plate.
^ Cut forward clutch piston inner seal.
^ Cut 3/4 clutch piston outer seal.
^ Input housing orifice cup plug blown out.
^ Input housing cracked or broken.
^ Mislocated valve body to spacer plate check ball(s).
^ Case damaged at the 2nd clutch apply piston pin bore causing the pin to drag/stick in the bore.
^ Input housing air bleed orifice cup plug with a check ball that does not seal.
In addition to the above items, a misadjusted shift cable has been found to cause these types of
concerns. When attempting to correct a slipping/missing second, third or fourth gear, the items
listed above should be inspected as possible causes. It is also important to reference the
appropriate Service Information for additional possible causes of these concerns.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Technical Service Bulletins > Page 7661
Shift Cable: Specifications
4L60-E
Shift Cable Grommet Screw
.............................................................................................................................................................
1.7 Nm (15 inch lbs.) Shift Control Cable Attachment
............................................................................................................................................................
20 Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Adjustments > 4L60-E
Shift Cable: Adjustments 4L60-E
Automatic Transmission Range Selector Cable Adjustment
1. Ensure that the steering column shift lever and the transmission manual shaft lever are in the
park position. 2. Raise the vehicle. Refer to Vehicle Lifting. 3. Pull back the white plastic cover (1)
on the center connector.
4. Pull up on the center tabs of the lock button (2).
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
shift cable end (2) during this procedure.
5. Release the shift cable end (2) and allow the blue spring to tension/adjust the shift cable system.
6. Pull the white cover (3) on the shift cable end (1) back.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Adjustments > 4L60-E > Page 7664
7. Push the natural colored lock button (2) down to engage the locking teeth on the shift cable end
(1).
8. Release the white cover (1).
9. Verify the white cover (1) conceals the natural colored lock (2).
10. If the white cover (1) does not conceal the natural colored lock (2), the shift cable must be
readjusted. 11. Test the transmission for proper shift operation. 12. If all of the gear positions
cannot be achieved, the shift cable must be readjusted.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Adjustments > 4L60-E > Page 7665
Shift Cable: Adjustments 4L80-E
Automatic Transmission Range Selector Cable Adjustment
1. Ensure that the steering column shift lever and the transmission manual shaft lever are in the
park position. 2. Raise the vehicle. Refer to Vehicle Lifting. 3. Pull back the white plastic cover (1)
on the center connector.
4. Pull up on the center tabs of the lock button (2).
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
shift cable end (2) during this procedure.
5. Release the shift cable end (2) and allow the blue spring to tension/adjust the shift cable system.
6. Pull the white cover (3) on the shift cable end (1) back.
7. Push the natural colored lock button (2) down to engage the locking teeth on the shift cable end
(1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Adjustments > 4L60-E > Page 7666
8. Release the white cover (1).
9. Verify the white cover (1) conceals the natural colored lock (2).
10. If the white cover (1) does not conceal the natural colored lock (2), the shift cable must be
readjusted. 11. Test the transmission for proper shift operation. 12. If all of the gear positions
cannot be achieved, the shift cable must be readjusted.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E
Shift Cable: Service and Repair 4L60-E
A/T Range Selector Cable Replacement (Front/Column End)
Automatic Transmission Range Selector Cable Replacement (Front/Column End)
Important: The range selector cable is a two piece cable assembly.
The front half (column end) or rear half (transmission end) of the range selector cable can be
removed without removing the other end/half of the range selector cable assembly.
Removal Procedure
1. Position the steering column shift lever to the park position. 2. Raise the vehicle. Refer to Vehicle
Lifting. 3. Ensure the transmission manual shaft is positioned to mechanical park. 4. Remove the
range selector cable end (2) from the transmission range selector lever ball stud (1).
5. Locate the center connector on the transmission range selector cable.
6. Pull back the white plastic cover (1) on the center connector.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7669
7. Pull up on the center tabs of the lock button (2).
Important: Do not reuse the existing E-clip. Discard the removed E-clip.
8. Ensure that the steering column shift lever remained in the park position for the best possible
access to the E-clip. Remove the E-clip by pulling
radially on the center section of the E-clip.
9. Pull the range selector cable center connector ends apart.
10. Lower the vehicle and ensure that the steering column shift lever is still in the park position. 11.
Remove the instrument panel knee bolster. 12. Pull back the carpet and insulation around the
driver's area.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7670
13. Remove the cable end (1) from the steering column ball stud. 14. Remove the retainer (2)
securing the cable to the steering column. 15. Depress the tangs and remove the cable from the
steering column bracket.
16. Remove the bolt securing the cable support to the brace.
Important: Avoid unnecessary twisting/bending of the range selector cable when removing the
cable from the support.
17. Remove the range selector cable from the support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7671
18. Remove the cable grommet from the floor panel. 19. Raise the vehicle. Refer to Vehicle Lifting.
20. Remove the two clips on the cable from the floor panel reinforcement. 21. Remove the cable
from the clips on the transfer case, if equipped. 22. Remove the front half (column end) of the
range selector cable assembly from the vehicle.
Installation Procedure
1. Route the cable through the hole in the floor panel. 2. Install the cable to the clips on the transfer
case, if equipped. 3. Install the two clips on the cable to the floor panel reinforcement. 4. Lower the
vehicle. 5. Ensure that the steering column shift lever is in the park position. 6. Install the cable
grommet to the floor panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7672
7. Install the cable to the steering column bracket. Ensure the tangs fully seat (snap) into the
steering column bracket. 8. Install the retainer (2) securing the cable to the steering column. 9.
Install the cable end (1) to the steering column ball stud.
10. Install the cable to the support.
Notice: Refer to Fastener Notice in Service Precautions.
11. Install the bolt securing the cable support to the brace.
^ Tighten the bolts to 10 Nm (89 inch lbs.).
12. Install the carpet and insulation around the driver's area. 13. Install the instrument panel knee
bolster. 14. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7673
15. Ensure that the transmission manual shaft lever is in the mechanical park position. 16. Install
the range selector cable end (2) to the transmission range selector lever ball stud (1).
17. The new front half (steering column end) of the cable will contain a new pre-installed E-clip. 18.
Grasp the front half (cab end) of the transmission cable (1) in the left hand and the rear half
(transmission end) of the transmission cable (2) in the
right hand.
19. Align the outside diameter of cable (2) with the inside of the diameter of cable (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7674
20. Push the end of the cable (2) inside the end of cable (1) until the blue spring on cable (2) is fully
compressed.
Pushing together the two ends of the cable will engage the inner wire and lock both cable wires
together.
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
cable end (2) during this procedure.
21. Release the cable end (2) and allow the blue spring to tension/adjust the cable system. 22. Pull
the white cover (3) on the cable end (1) back.
23. Push the natural colored lock button (2) down to engage the locking teeth on the cable end (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7675
24. Release the white cover (1).
25. Verify the white cover (1) conceals the natural colored lock (2). 26. If the white cover (1) does
not conceal the natural colored lock (2), repeat the cable adjustment procedure. 27. Lower the
vehicle and test the transmission for proper shift operation. 28. If all of the gear positions cannot be
achieved, repeat the cable adjustment procedure.
A/T Range Selector Cable Replacement (Rear/Transmission End)
Automatic Transmission Range Selector Cable Replacement (Rear/Transmission End)
Important: The range selector cable is a two piece cable assembly.
The front half (column end) or rear half (transmission end) of the range selector cable can be
removed without removing the other end/half of the range selector cable assembly.
Removal Procedure
1. Position the steering column shift lever to the park position. 2. Raise the vehicle. Refer to Vehicle
Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7676
3. Ensure the transmission manual shaft is positioned to mechanical park. 4. Remove the range
selector cable end (2) from the transmission range selector lever ball stud (1).
5. Locate the center connector on the transmission range selector cable.
6. Pull back the white plastic cover (1) on the center connector.
7. Pull up on the center tabs of the lock button (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7677
Important: Do not reuse the existing E-clip. Discard the removed E-clip.
8. Ensure that the steering column shift lever remained in the park position for the best possible
access to the E-clip. Remove the E-clip by pulling
radially on the center section of the E-clip.
9. Pull the range selector cable center connector ends apart.
10. Remove the retainer that secures the cable to the bracket. 11. Depress the tangs and remove
the cable from the bracket. 12. Remove the cable to from the clips on the transfer case, if
equipped. 13. Remove the rear half (transmission end) of the range selector cable from the vehicle.
Installation Procedure
1. Install the rear half transmission end of the range selector cable to the vehicle. 2. Install the
cable to the clips on the transfer case, if equipped.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7678
3. Align and install the cable to the bracket. 4. Install the retainer that secures the cable to the
bracket.
5. Install a new E-clip to the front half (steering column end) of the cable.
6. Ensure that the transmission manual shaft lever is in the mechanical park position. 7. Install the
range selector cable end (2) to the transmission range selector lever ball stud (1).
8. Grasp the front half (steering column end) of the transmission cable (1) in the left hand and the
rear half (transmission end) of the transmission
cable (2) in the right hand.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7679
9. Align the outside diameter of cable (2) with the inside of the diameter of cable (1).
10. Push the end of the cable (2) inside the end of cable (1) until the blue spring on cable (2) is fully
compressed.
Pushing together the two ends of the cable will engage the inner wire and lock both cable wires
together.
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
cable end (2) during this procedure.
11. Release the cable end (2) and allow the blue spring to tension/adjust the cable system. 12. Pull
the white cover (3) on the cable end (1) back.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7680
13. Push the natural colored lock button (2) down to engage the locking teeth on the cable end (1).
14. Release the white cover (1).
15. Verify the white cover (1) conceals the natural colored lock (2). 16. If the white cover (1) does
not conceal the natural colored lock (2), repeat the cable adjustment procedure. 17. Lower the
vehicle and test the transmission for proper shift operation. 18. If all of the gear positions cannot be
achieved, repeat the cable adjustment procedure.
A/T Range Selector Cable Bracket Replacement
Automatic Transmission Range Selector Cable Bracket Replacement
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7681
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Disconnect the transmission range selector cable from the shift lever and the
bracket (2). 5. Remove the bolts (1) securing the transmission range selector cable bracket (2) to
the transmission. 6. Remove the transmission range selector cable bracket from the vehicle.
Installation Procedure
1. Install the transmission range selector cable bracket to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the transmission range selector cable bracket bolts (1).
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
3. Install the transmission range selector cable to the bracket (2) and the lever. 4. Lower the
vehicle. 5. Check the vehicle for proper operation. If adjustment of the cable is necessary, refer to
Automatic Transmission Range Selector Cable Adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7682
Shift Cable: Service and Repair 4L80-E
A/T Range Selector Cable Replacement (Front/Column End)
Automatic Transmission Range Selector Cable Replacement (Front/Column End)
Important: The range selector cable is a two piece cable assembly.
The front half (column end) or rear half (transmission end) of the range selector cable can be
removed without removing the other end/half of the range selector cable assembly.
Removal Procedure
1. Position the steering column shift lever to the park position. 2. Raise the vehicle. Refer to Vehicle
Lifting. 3. Ensure the transmission manual shaft is positioned to mechanical park. 4. Remove the
range selector cable end (2) from the transmission range selector lever ball stud (1).
5. Locate the center connector on the transmission range selector cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7683
6. Pull back the white plastic cover (1) on the center connector.
7. Pull up on the center tabs of the lock button (2).
Important: Do not reuse the existing E-clip. Discard the removed E-clip.
8. Ensure that the steering column shift lever remained in the park position for the best possible
access to the E-clip. Remove the E-clip by pulling
radially on the center section of the E-clip.
9. Pull the range selector cable center connector ends apart.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7684
10. Lower the vehicle and ensure that the steering column shift lever is still in the park position. 11.
Remove the instrument panel knee bolster. 12. Pull back the carpet and insulation around the
driver's area.
13. Remove the cable end (1) from the steering column ball stud. 14. Remove the retainer (2)
securing the cable to the steering column. 15. Depress the tangs and remove the cable from the
steering column bracket.
16. Remove the bolt securing the cable support to the brace.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7685
Important: Avoid unnecessary twisting/bending of the range selector cable when removing the
cable from the support.
17. Remove the range selector cable from the support.
18. Remove the cable grommet from the floor panel. 19. Raise the vehicle. Refer to Vehicle Lifting.
20. Remove the two clips on the cable from the floor panel reinforcement. 21. Remove the cable
from the clips on the transfer case, if equipped. 22. Remove the front half (column end) of the
range selector cable assembly from the vehicle.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7686
1. Route the cable through the hole in the floor panel. 2. Install the cable to the clips on the transfer
case, if equipped. 3. Install the two clips on the cable to the floor panel reinforcement. 4. Lower the
vehicle. 5. Ensure that the steering column shift lever is in the park position. 6. Install the cable
grommet to the floor panel.
7. Install the cable to the steering column bracket. Ensure the tangs fully seat (snap) into the
steering column bracket. 8. Install the retainer (2) securing the cable to the steering column. 9.
Install the cable end (1) to the steering column ball stud.
10. Install the cable to the support.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7687
Notice: Refer to Fastener Notice in Service Precautions.
11. Install the bolt securing the cable support to the brace.
^ Tighten the bolts to 10 Nm (89 inch lbs.).
12. Install the carpet and insulation around the driver's area. 13. Install the instrument panel knee
bolster. 14. Raise the vehicle. Refer to Vehicle Lifting.
15. Ensure that the transmission manual shaft lever is in the mechanical park position. 16. Install
the range selector cable end (2) to the transmission range selector lever ball stud (1).
17. The new front half (steering column end) of the cable will contain a new pre-installed E-clip. 18.
Grasp the front half (cab end) of the transmission cable (1) in the left hand and the rear half
(transmission end) of the transmission cable (2) in the
right hand.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7688
19. Align the outside diameter of cable (2) with the inside of the diameter of cable (1).
20. Push the end of the cable (2) inside the end of cable (1) until the blue spring on cable (2) is fully
compressed.
Pushing together the two ends of the cable will engage the inner wire and lock both cable wires
together.
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
cable end (2) during this procedure.
21. Release the cable end (2) and allow the blue spring to tension/adjust the cable system. 22. Pull
the white cover (3) on the cable end (1) back.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7689
23. Push the natural colored lock button (2) down to engage the locking teeth on the cable end (1).
24. Release the white cover (1).
25. Verify the white cover (1) conceals the natural colored lock (2). 26. If the white cover (1) does
not conceal the natural colored lock (2), repeat the cable adjustment procedure. 27. Lower the
vehicle and test the transmission for proper shift operation. 28. If all of the gear positions cannot be
achieved, repeat the cable adjustment procedure.
A/T Range Selector Cable Replacement (Rear/Transmission End)
Automatic Transmission Range Selector Cable Replacement (Rear/Transmission End)
Important: The range selector cable is a two piece cable assembly.
The front half (column end) or rear half (transmission end) of the range selector cable can be
removed without removing the other end/half of the range selector cable assembly.
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7690
1. Position the steering column shift lever to the park position. 2. Raise the vehicle. Refer to Vehicle
Lifting. 3. Ensure the transmission manual shaft is positioned to mechanical park. 4. Remove the
range selector cable end (2) from the transmission range selector lever ball stud (1).
5. Locate the center connector on the transmission range selector cable.
6. Pull back the white plastic cover (1) on the center connector.
7. Pull up on the center tabs of the lock button (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7691
Important: Do not reuse the existing E-clip. Discard the removed E-clip.
8. Ensure that the steering column shift lever remained in the park position for the best possible
access to the E-clip. Remove the E-clip by pulling
radially on the center section of the E-clip.
9. Pull the range selector cable center connector ends apart.
10. Remove the retainer that secures the cable to the bracket. 11. Depress the tangs and remove
the cable from the bracket. 12. Remove the cable to from the clips on the transfer case, if
equipped. 13. Remove the rear half (transmission end) of the range selector cable from the vehicle.
Installation Procedure
1. Install the rear half transmission end of the range selector cable to the vehicle. 2. Install the
cable to the clips on the transfer case, if equipped. 3. Align and install the cable to the bracket. 4.
Install the retainer that secures the cable to the bracket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7692
5. Install a new E-clip to the front half (steering column end) of the cable.
6. Ensure that the transmission manual shaft lever is in the mechanical park position. 7. Install the
range selector cable end (2) to the transmission range selector lever ball stud (1).
8. Grasp the front half (steering column end) of the transmission cable (1) in the left hand and the
rear half (transmission end) of the transmission
cable (2) in the right hand.
9. Align the outside diameter of cable (2) with the inside of the diameter of cable (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7693
10. Push the end of the cable (2) inside the end of cable (1) until the blue spring on cable (2) is fully
compressed.
Pushing together the two ends of the cable will engage the inner wire and lock both cable wires
together.
Important: This step must be performed correctly to avoid a misadjusted cable. Do not grasp the
cable end (2) during this procedure.
11. Release the cable end (2) and allow the blue spring to tension/adjust the cable system. 12. Pull
the white cover (3) on the cable end (1) back.
13. Push the natural colored lock button (2) down to engage the locking teeth on the cable end (1).
14. Release the white cover (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7694
15. Verify the white cover (1) conceals the natural colored lock (2). 16. If the white cover (1) does
not conceal the natural colored lock (2), repeat the cable adjustment procedure. 17. Lower the
vehicle and test the transmission for proper shift operation. 18. If all of the gear positions cannot be
achieved, repeat the cable adjustment procedure.
A/T Range Selector Cable Bracket Replacement
Automatic Transmission Range Selector Cable Bracket Replacement
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Disconnect the transmission range selector cable from the shift lever and the
bracket (2). 5. Remove the bolts (1) securing the transmission range selector cable bracket (2) to
the transmission. 6. Remove the transmission range selector cable bracket from the vehicle.
Installation Procedure
1. Install the transmission range selector cable bracket to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Shift Linkage, A/T >
Shift Cable, A/T > Component Information > Service and Repair > 4L60-E > Page 7695
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the transmission range selector cable bracket bolts (1).
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
3. Install the transmission range selector cable to the bracket (2) and the lever. 4. Lower the
vehicle. 5. Check the vehicle for proper operation. If adjustment of the cable is necessary, refer to
Automatic Transmission Range Selector Cable Adjustment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > Customer Interest for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T - 4L60/65E,
No Reverse/2nd or 4th Gear
Sun Gear: Customer Interest A/T - 4L60/65E, No Reverse/2nd or 4th Gear
TECHNICAL
Bulletin No.: 00-07-30-022D
Date: June 10, 2008
Subject: No Reverse, Second Gear or Fourth Gear (Replace Reaction Sun Shell with More Robust
Heat Treated Parts)
Models: 1993 - 2005 GM Passenger Cars and Light Duty Trucks 2003 - 2005 HUMMER H2
with 4L60/65-E Automatic Transmission (RPOs M30 or M32)
Supercede: This bulletin is being revised to add 2005 model year to the parts information. Please
discard Corporate Bulletin Number 00-07-30-022C (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a no reverse, no second or no fourth gear condition. First and
third gears will operate properly.
Cause
The reaction sun gear (673) may not hold inside the reaction sun shell (670).
Correction
Important:
There are FOUR distinct groups of vehicles and repair procedures involved. Vehicles built in the
2001 model year and prior that make use of a reaction shaft to shell thrust washer:
^ The sun shell can be identified by four square holes used to retain the thrust washer. Use
reaction sun shell P/N 24228345, reaction carrier to shell thrust washer (699B) P/N 8642202 and
reaction sun gear shell thrust washer (674) P/N 8642331er (674) P/N 8642331along with the
appropriate seals and washers listed below.
^ Vehicles built in the 2001 model year and prior that have had previous service to the reaction sun
shell: It is possible that some 2001 and prior model year vehicles have had previous service to the
reaction sun shell. At the time of service, these vehicles may have been updated with a Reaction
Sun Shell Kit (Refer to Service Bulletin 020730003) without four square holes to retain the thrust
washer. If it is found in a 2001 model year and prior vehicles that the reaction sun shell DOES NOT
have four square holes to retain the thrust washer, these vehicles must be serviced with P/Ns
24229825 (674), 24217328 and 8642331 along with the appropriate seals and washers listed
below.
^ Vehicles built in the 2001 model year and later that make use of a reaction shaft to shell thrust
bearing: The sun shell can be identified by no holes to retain the thrust washer. Use reaction sun
shell, P/N 24229825, reaction carrier shaft to shell thrust bearing (669A), P/N 24217328 and
reaction sun gear shell thrust washer (674), P/N 8642331 along with the appropriate seals and
washers listed below.
^ Vehicles built from November, 2001 through June, 2002: These vehicles should have the reaction
carrier shaft replaced when the sun shell is replaced. Use shell kit P/N 24229853, which contains a
sun shell (670), a reaction carrier shaft (666), a reaction carrier shaft to shell thrust bearing (669A)
and a reaction sun gear shell thrust washer (674). The appropriate seals and washers listed below
should also be used.
When servicing the transmission as a result of this condition, the transmission oil cooler and lines
MUST be flushed. Refer to Corporate Bulletin Number 02-07-30-052.
Follow the service procedure below for diagnosis and correction of the no reverse, no second, no
forth condition.
Important:
If metallic debris is found on the transmission magnet, the transmission must be completely
disassembled and cleaned. Metallic debris is defined as broken parts and pieces of internal
transmission components. This should not be confused with typical "normal" fine particles found on
all transmission magnets. Failure to properly clean the transmission case and internal components
may lead to additional repeat repairs.
1. Remove the transmission oil pan and inspect the magnet in the bottom of the pan for metal
debris. Refer to SI Document ID # 825141.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > Customer Interest for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T - 4L60/65E,
No Reverse/2nd or 4th Gear > Page 7704
2. Remove the transmission from the vehicle. Refer to the appropriate SI document.
Important:
^ Inspect all the transmission components for damage or wear. Replace all damaged or worn
components. The parts shown above should be sufficient to correct this concern.
^ This condition does not normally require replacement of the transmission completely.
Components such as clutches, valve body, pump and torque converters will NOT require
replacement to correct this condition.
Disassemble the transmission and replace the appropriate parts listed below. Refer to the Unit
Repair Manual - Repair Instructions.
3. Reinstall the transmission in the vehicle. Refer to appropriate service information.
When servicing the transmission as a result of this condition, the transmission oil cooler and lines
MUST be flushed. Refer to Corporate Bulletin Number 02-07-30-052.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > Customer Interest for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T - 4L60/65E,
No Reverse/2nd or 4th Gear > Page 7705
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T
- 4L60/65E, No Reverse/2nd or 4th Gear
Sun Gear: All Technical Service Bulletins A/T - 4L60/65E, No Reverse/2nd or 4th Gear
TECHNICAL
Bulletin No.: 00-07-30-022D
Date: June 10, 2008
Subject: No Reverse, Second Gear or Fourth Gear (Replace Reaction Sun Shell with More Robust
Heat Treated Parts)
Models: 1993 - 2005 GM Passenger Cars and Light Duty Trucks 2003 - 2005 HUMMER H2
with 4L60/65-E Automatic Transmission (RPOs M30 or M32)
Supercede: This bulletin is being revised to add 2005 model year to the parts information. Please
discard Corporate Bulletin Number 00-07-30-022C (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a no reverse, no second or no fourth gear condition. First and
third gears will operate properly.
Cause
The reaction sun gear (673) may not hold inside the reaction sun shell (670).
Correction
Important:
There are FOUR distinct groups of vehicles and repair procedures involved. Vehicles built in the
2001 model year and prior that make use of a reaction shaft to shell thrust washer:
^ The sun shell can be identified by four square holes used to retain the thrust washer. Use
reaction sun shell P/N 24228345, reaction carrier to shell thrust washer (699B) P/N 8642202 and
reaction sun gear shell thrust washer (674) P/N 8642331er (674) P/N 8642331along with the
appropriate seals and washers listed below.
^ Vehicles built in the 2001 model year and prior that have had previous service to the reaction sun
shell: It is possible that some 2001 and prior model year vehicles have had previous service to the
reaction sun shell. At the time of service, these vehicles may have been updated with a Reaction
Sun Shell Kit (Refer to Service Bulletin 020730003) without four square holes to retain the thrust
washer. If it is found in a 2001 model year and prior vehicles that the reaction sun shell DOES NOT
have four square holes to retain the thrust washer, these vehicles must be serviced with P/Ns
24229825 (674), 24217328 and 8642331 along with the appropriate seals and washers listed
below.
^ Vehicles built in the 2001 model year and later that make use of a reaction shaft to shell thrust
bearing: The sun shell can be identified by no holes to retain the thrust washer. Use reaction sun
shell, P/N 24229825, reaction carrier shaft to shell thrust bearing (669A), P/N 24217328 and
reaction sun gear shell thrust washer (674), P/N 8642331 along with the appropriate seals and
washers listed below.
^ Vehicles built from November, 2001 through June, 2002: These vehicles should have the reaction
carrier shaft replaced when the sun shell is replaced. Use shell kit P/N 24229853, which contains a
sun shell (670), a reaction carrier shaft (666), a reaction carrier shaft to shell thrust bearing (669A)
and a reaction sun gear shell thrust washer (674). The appropriate seals and washers listed below
should also be used.
When servicing the transmission as a result of this condition, the transmission oil cooler and lines
MUST be flushed. Refer to Corporate Bulletin Number 02-07-30-052.
Follow the service procedure below for diagnosis and correction of the no reverse, no second, no
forth condition.
Important:
If metallic debris is found on the transmission magnet, the transmission must be completely
disassembled and cleaned. Metallic debris is defined as broken parts and pieces of internal
transmission components. This should not be confused with typical "normal" fine particles found on
all transmission magnets. Failure to properly clean the transmission case and internal components
may lead to additional repeat repairs.
1. Remove the transmission oil pan and inspect the magnet in the bottom of the pan for metal
debris. Refer to SI Document ID # 825141.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T
- 4L60/65E, No Reverse/2nd or 4th Gear > Page 7711
2. Remove the transmission from the vehicle. Refer to the appropriate SI document.
Important:
^ Inspect all the transmission components for damage or wear. Replace all damaged or worn
components. The parts shown above should be sufficient to correct this concern.
^ This condition does not normally require replacement of the transmission completely.
Components such as clutches, valve body, pump and torque converters will NOT require
replacement to correct this condition.
Disassemble the transmission and replace the appropriate parts listed below. Refer to the Unit
Repair Manual - Repair Instructions.
3. Reinstall the transmission in the vehicle. Refer to appropriate service information.
When servicing the transmission as a result of this condition, the transmission oil cooler and lines
MUST be flushed. Refer to Corporate Bulletin Number 02-07-30-052.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Sun Gear > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Sun Gear: > 00-07-30-022D > Jun > 08 > A/T
- 4L60/65E, No Reverse/2nd or 4th Gear > Page 7712
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter >
Component Information > Technical Service Bulletins > A/T - Torque Converter Replacement Information
Torque Converter: Technical Service Bulletins A/T - Torque Converter Replacement Information
INFORMATION
Bulletin No.: 01-07-30-010C
Date: May 12, 2008
Subject: Automatic Transmission/Transaxle Torque Converter Replacement
Models: 2009 and Prior GM Passenger Cars and Trucks 2009 and Prior HUMMER H2, H3 2009
and Prior Saturn Cars and Light Duty Trucks (Except VTi Equipped Vehicles (RPO M16 and M75)
2009 and Prior Saab 9-7X
with ALL Automatic Transmissions and Transaxles
Supercede:
This bulletin is being revised to add the 2007-2009 model years. Please discard Corporate Bulletin
Number 01-07-30-010B (Section 07 - Transmission/Transaxle).
The purpose of this bulletin is to help technicians determine when a torque converter should be
replaced. Below is a list of general guidelines to follow.
The converter should NOT be replaced if the following apply:
^ DTC P0742 - TCC stuck on is set. This code is almost always the result of a controls condition
(i.e. stuck TCC solenoid/valve). Experience has shown that this code rarely indicates a mechanical
concern within the torque converter.
^ The fluid has an odor or is discolored but no evidence of metal contamination.
^ Fine metal particles (traces of metal flakes/gray color to fluid ) are found in the converter. This is
not harmful to the torque converter.
^ The vehicle has been exposed to high mileage.
^ A small amount of wear appears on the hub where the oil pump drive gear mates to the converter
(RWD only). A certain amount of such wear is normal for both the hub and oil pump gear. Neither
the converter nor the front pump assembly should be replaced.
The torque converter should be replaced under any of the following conditions:
^ The vehicle has TCC shudder and/or no TCC apply. First complete all electrical and hydraulic
diagnosis and check for proper engine operation. The converter clutch may be damaged. Also the
converter bushing and/or internal 0-ring may be damaged.
^ Evidence of damage to the oil pump assembly pump shaft turbine shaft drive sprocket support
and bearing or metal chips/debris in the converter.
^ Metal chips/debris are found in the converter or when flushing the cooler and the cooler lines.
^ External leaks in the hub weld area lug weld or closure weld.
^ Converter pilot is broken damaged or fits poorly into the crankshaft.
^ The converter hub is scored or damaged.
^ The transmission oil is contaminated with engine coolant engine oil or water.
^ If excessive end play is found after measuring the converter for proper end play (refer to Service
Manual).
^ If metal chips/debris are found in the fluid filter or on the magnet and no internal parts in the unit
are worn or damaged. This indicates that the material came from the converter.
^ The converter has an unbalanced condition that results in a vibration that cannot be corrected by
following Converter Vibration Procedures.
^ Blue converter or dark circular ring between lugs. This condition will also require a complete
cleaning of the cooler and a check for adequate flow
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter >
Component Information > Technical Service Bulletins > A/T - Torque Converter Replacement Information > Page 7717
through the cooler.
^ Converter bearing noise determined by noise from the bell housing area in Drive or Reverse at
idle. The noise is gone in Neutral and Park.
^ If silicon from the viscous clutch is found in the lower pan (4T80-E ONLY).
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Check Valve > Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line
Fitting
Torque Converter Check Valve: Technical Service Bulletins A/T - Revised Converter Check
Valve/Cooler Line Fitting
INFORMATION
Bulletin No.: 04-07-30-017B
Date: November 25, 2008
Subject: Information on 4T65-E MN7, M15, M76, MN3 Automatic Transmission Case, Cooler
Fitting and Torque Converter Drain Back Check Ball Change
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks
with one of the HYDRA-MATIC(R) Automatic Transmissions shown above.
Supercede:
This bulletin is being revised to update the Parts Information. Please discard Corporate Bulletin
Number 04-07-30-017A (Section 07 - Transmission/Transaxle).
Effective with Julian date 4019 (January 19, 2004), the 4T65E transaxle cases and cooler fittings
have changed and are not interchangeable with past models. The technician may find that when
replacing the inlet or outlet transmission cooler lines, the new lines cannot be connected to the
transmission.
A change to the transmission cooler line fittings was implemented in production on February 1,
2004. The cooler line fittings were changed to a design with a longer lead in pilot (1). The cooler
line fittings with the longer lead in pilot will not fit on models built before February 1, 2004.
The longer lead in pilot fittings (1) (9/16-18 UNF) have replaced the shorter lead in pilot fittings (2)
(3/8-18 NPSF w/check ball & 1/4-18 NPSF).
If the transmission cooler lines will not connect, then replace them with the following cooler line
fittings as appropriate with the older, shorter lead in pilot design:
^ For vehicles built prior to February 1, 2004, use Transmission Fluid Cooler Inlet Hose, P/N
20793004.
^ For vehicles built after February 1, 2004, use Transmission Fluid Cooler Inlet Hose, second
design P/N 15264588.
^ For vehicles built prior to February 1, 2004, use Transmission Fluid Cooler Outlet Hose, P/N
20793005.
^ For vehicles built after February 1, 2004, use Transmission Fluid Cooler Outlet Hose, second
design P/N 15264589.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Check Valve > Component Information > Technical Service Bulletins > A/T - Revised Converter Check Valve/Cooler Line
Fitting > Page 7722
The torque specification has changed for the fittings to case. The torque has changed from 38 Nm
(28 lb ft) to 32 Nm (23 lb ft).
Tighten
Tighten the new cooler fittings to 32 Nm (23 lb ft).
The converter drain back check ball (420C) has been removed from the cooler line fitting and is
now located in the channel plate.
If you get a concern of no movement in the morning or after sitting for several hours, the cooler
check ball should be inspected.
The best way to determine where the check ball is located is to look at the cooler line fittings. The
old fittings are different sizes (3/8-18 NPSF & 1/4-18 NPSF) and would contain the cooler check
ball. The new fittings are the same size as each other (9/16-18 UNF) and do not have a cooler
check ball.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Specifications
Torque Converter Clutch Solenoid: Specifications
4L60-E
TCC Solenoid Assembly to Case Bolt
..................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E
Torque Converter Clutch Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Diagrams > 4L60-E > Page 7728
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E
Torque Converter Clutch Solenoid: Service and Repair 4L60-E
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid, TCC Solenoid, and Wiring
Harness
^ Tools Required J 28458 Seal Protector Retainer Installer
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
the filter. 3. Disconnect the transmission harness 20-way connector from the transmission internal
harness pass-through connector.
Depress both tabs on the connector and pull straight up; do not pry the connector.
Important: Removal of the valve body is not necessary for the following procedure.
4. Remove the 1-2 accumulator assembly. Do not remove the spacer plate.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7731
6. Remove the TCC PWM solenoid retainer. 7. Remove the TCC PWM solenoid in order to access
one of the TCC solenoid retaining bolts.
8. Remove the pressure control solenoid retainer. 9. Remove the pressure control solenoid.
10. Remove the TCC solenoid retaining bolts and the valve body bolts, which retain the internal
wiring harness.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7732
11. Using J28458, release the pass-through electrical connector from the transmission case.
11.1. Use the small end of the J28458 over the top of the connector.
11.2. Twist in order to release the four tabs retaining the connector.
11.3. Pull the harness connector down through the transmission case.
12. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the
transmission case.
13. Inspect the TCC solenoid and wiring harness assembly for the following defects:
^ Damage
^ Cracked connectors
^ Exposed wires
^ Loose pins
Installation Procedure
1. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the
transmission. 2. Install the pass-through electrical connector to the transmission case.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7733
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the valve body bolts, which retain the internal wiring harness and install the TCC solenoid
retaining bolts.
^ Tighten the control valve body retaining bolts to 11 Nm (97 inch lbs.).
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
4. Install the pressure control solenoid.
Ensure that the electrical tabs are facing outboard.
5. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
6. Install the TCC PWM solenoid to the control valve body. 7. Install the TCC PWM solenoid
retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7734
8. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
9. Install the 1-2 accumulator.
10. Connect the transmission harness 20-way connector to the transmission pass-through
connector.
Align the arrows on each half of the connector and insert straight down.
11. Install the transmission oil pan and filter. 12. Lower the vehicle. 13. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7735
Torque Converter Clutch Solenoid: Service and Repair 4L80-E
Torque Converter Clutch (TCC) Valve and Spring Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the oil filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the valve bore plug retainer ring (1).
4. Remove the following parts:
^ The valve bore plug
^ The TCC valve
^ The TCC valve spring
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Clutch Solenoid, A/T > Component Information > Service and Repair > 4L60-E > Page 7736
1. Install the following parts:
^ The TCC valve spring
^ The TCC valve
^ The valve bore plug
2. Install the valve bore plug retainer ring (1). 3. Install the transmission oil pan and oil filter. 4.
Lower the vehicle. 5. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Torque Converter
Cover > Component Information > Specifications
Torque Converter Cover: Specifications
4L60-E
Converter Cover Bolt ...........................................................................................................................
............................................. 10 Nm (89 inch lbs.)
4L80-E
Flywheel Housing Cover to Transmission
........................................................................................................................................... 7 Nm (62
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush
Transmission Cooler: Technical Service Bulletins A/T - Fluid Oil Cooler Flush
INFORMATION
Bulletin No.: 02-07-30-052G
Date: March 02, 2011
Subject: Automatic Transmission Oil Cooler Flush and Flow Test Essential Tool J 45096
TransFlow(R)
Models:
2011 and Prior Passenger Cars and Light Duty Trucks 2003-2010 HUMMER H2 2006-2010
HUMMER H3 with Automatic Transmission/Transaxle including Allison(R) Transmissions
Supercede: This bulletin is being revised to update the model years. Please discard Corporate
Bulletin Number 02-07-30-052F (Section 07 - Transmission/Transaxle).
Important All labor operations that include removal of the transmission from the vehicle include
labor time to flush the transmission oil cooler system.
The J 45096 transmission oil cooling system flush and flow test tool replaces current tool J
35944-A. J 45096 is a self-contained unit utilizing a 12-volt flow meter, shop air supply and
DEXRON(R) VI automatic transmission fluid (ATF). In the flush mode, transmission fluid is cycled
through the transmission oil cooling system. High-pressure air is automatically injected into the fluid
stream adding agitation to the ATF oil to enhance the removal of contaminated ATF oil and debris.
In the flow mode, an electronic flow meter is used to measure the flow capability of the ATF oil
cooling system. A digital display indicates the ATF oil flow rate in gallons per minute (GPM) along
with the amount of ATF oil in the supply vessel, supply vessel ATF oil temperature, machine cycles
and the operating mode. The supply oil vessel has 30 L (32 qt) capacity and the waste oil vessel
has 32 L (34 qt) capacity. The waste oil vessel is constructed of a translucent composite material
that allows the user to easily identify the oil level. The waste oil vessel can accommodate vacuum
evacuation and gravity draining. In the code mode, a random, encrypted code is generated that can
be used for verification of flow test results.
Current essential cooler line adapters are used to connect the J 45096 to the automatic
transmission oil cooler lines that allows J 45096 to adapt to General Motors passenger cars and
light duty trucks, current and past models (except the Pontiac Vibe, Wave and Chevrolet Aveo).
The tool may be adapted for use on the Pontiac Vibe, Wave and Chevrolet Aveo by dealership
personnel with a barbed hose connector and rubber hose obtained locally. The
Vibe's/Wave's/Aveo's transmission has a transmission oil requirement which is slightly different
than DEXRON(R) VI ATF. However, flushing the cooler with DEXRON(R) VI automatic
transmission fluid is an acceptable service procedure. Very little fluid remains in the cooler after the
flush procedure and the residual DEXRON(R) VI ATF in the cooler is compatible with the
Vibe's/Wave's/Aveo's transmission fluid.
Notice
Insufficient oil flow through the ATF oil cooling system will cause premature transmission failure.
The required minimum ATF oil flow rate reading is directly related to the supply oil temperature.
Refer to the flow rate reference chart for the oil flow rate specification based on the temperature of
the ATF in the supply vessel.
Helpful Hints for Maintaining the Temperature at or above 18°C (65°F)
Important
- The temperature of the supply vessel oil must be 18°C (65°F) or greater for J 45096 to operate. It
is recommended to store the J 45096 in an area of the dealership where the room temperature
remains at or above 18°C (65°F) when not in use.
- Do not attempt to increase the fluid temperature in the Transflow(R) machine with an engine oil
dipstick, or any other immersion type heater. The Transflow(R) machine has a check valve in the
supply reservoir. Inserting a heater will damage the check valve and the subsequent repair
expense would be the dealer's responsibility.
- A heater blanket, P/N J-45096-10, is available for the Transflow(R) transmission cooling system
flushing tool. This heater fastens around the Transflow(R) internal supply vessel and runs on 110
volts AC. The heater will warm the ATF in the supply vessel to at least 18°C (65° F) and has a
thermostat to hold a constant temperature.
Store the Transmission Cooling System Service Tool, J 45096, Transflow(R) machine in a room
where the temperature is maintained at or above 18°C (65°F).
Keep the ATF level in the reservoir low when the Transmission Cooling System Service Tool, J
45096, Transflow(R), is not in use. Store several gallons of oil in an area where the temperature is
maintained at or above 18°C (65°F). Fill the reservoir of the J 45096 as needed before using the
machine on
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7744
each repair.
With the ATF in a tightly sealed container, place the container in a tub of hot water for a period of
time. Then pour the ATF into the reservoir. This method works best with a low fluid level in the
reservoir.
Place the Transflow(R) machine in the direct sunlight with the cabinet door open to expose the
reservoir to the rays of the warm sun.
Flush / Flow Test Procedure
Important All labor operations that include removal of the transmission from the vehicle and require
the transmission oil pan or transmission side cover to be removed include labor time to flush the
transmission oil cooler system.
Refer to SI for Automatic Transmission Oil Cooler Flushing and Flow Test J 45096 for the
appropriate procedure.
Important The J 45096 can be used to flush the transmission oil cooler system on an Allison
equipped vehicle, but the flow meter should not be utilized. Refer to SI for Automatic Transmission
Oil Cooler Flushing and Flow Test J 45096 for the appropriate flow check procedure.
Machine Displays
After completion of the flush and flow test, the following information is to be recorded on the repair
order. This information is displayed on the Transmission Cooling System Service Tool, J 45096,
Transflow(R) machine when the dial is in the code position.
- Tested flow rate (displayed in Gallons Per Minute (GPM)
- Temperature (displayed is degrees Fahrenheit)
- Cycle number (a number)
- Seven digit Alpha/Numeric flow code (i.e. A10DFB2)
Warranty Information
Important All labor operations that include removal of the transmission from the vehicle include
labor time to flush the transmission oil cooler system.
Performing a transmission oil cooling system flush and flow test will use between 4.7-7.5 L (5-8 qts)
of DEXRON(R)VI transmission fluid. The amount
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7745
of transmission fluid (ATF), (DEXRON(R)VI) (fluid) that is to be charged for the flush portion of the
repair should not exceed the allowable charge for 7.5 L (2 gal) of fluid. This expense should be
shown in the Parts Section of the warranty claim document.
The Seven digit Alpha/Numeric flow code, i.e. A10DFB2, "MUST" be written on the job card and
placed in the comments section of the warranty claim. Any repair that requires the technician to
contact the Product Quality Center (PQC) must also include the seven digit flow code. The agent
will request the seven digit flow code and add the information to the PQC case prior to providing
authorization for the warranty claim.
The Seven digit Alpha/Numeric flow code, i.e. A10DFB2, "MUST" be written on the job card,
entered in the warranty claim labor operation Flush Code additional field (when available) and
placed in the comments section of the warranty claim. Any repair that requires the technician to
contact the Product Quality Center (PQC) must also include the seven digit flow code. The agent
will request the seven digit flow code and add the information to the PQC case prior to providing
authorization for the warranty claim.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7746
Transmission Cooler: Technical Service Bulletins A/T - Water Or Coolant Contamination
Information
INFORMATION
Bulletin No.: 08-07-30-035B
Date: November 01, 2010
Subject: Information on Water or Ethylene Glycol in Transmission Fluid
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks with Automatic Transmission
Supercede: This bulletin is being revised to update model years. Please discard Corporate Bulletin
Number 08-07-30-035A (Section 07 - Transmission/Transaxle).
Water or ethylene glycol in automatic transmission fluid (ATF) is harmful to internal transmission
components and will have a negative effect on reliability and durability of these parts. Water or
ethylene glycol in ATF will also change the friction of the clutches, frequently resulting in shudder
during engagement or gear changes, especially during torque converter clutch engagement.
Indications of water in the ATF may include:
- ATF blowing out of the transmission vent tube.
- ATF may appear cloudy or, in cases of extreme contamination, have the appearance of a
strawberry milkshake.
- Visible water in the oil pan.
- A milky white substance inside the pan area.
- Spacer plate gaskets that appear to be glued to the valve body face or case.
- Spacer plate gaskets that appear to be swollen or wrinkled in areas where they are not
compressed.
- Rust on internal transmission iron/steel components.
If water in the ATF has been found and the source of the water entry has not been identified, or if a
leaking in-radiator transmission oil cooler is suspected (with no evidence of cross-contamination in
the coolant recovery reservoir), a simple and quick test kit is available that detects the presence of
ethylene glycol in ATF. The "Gly-Tek" test kit, available from the Nelco Company, should be
obtained and the ATF tested to make an accurate decision on the need for radiator replacement.
This can help to prevent customer comebacks if the in-radiator transmission oil cooler is leaking
and reduce repair expenses by avoiding radiator replacement if the cooler is not leaking. These
test kits can be obtained from:
Nelco Company
Test kits can be ordered by phone or through the website listed above. Orders are shipped
standard delivery time but can be shipped on a next day delivery basis for an extra charge. One
test kit will complete 10 individual fluid sample tests. For vehicles repaired under warranty, the cost
of the complete test kit plus shipping charges should be divided by 10 and submitted on the
warranty claim as a net item.
The transmission should be repaired or replaced based on the normal cost comparison procedure.
Important If water or coolant is found in the transmission, the following components MUST be
replaced.
- Replace all of the rubber-type seals.
- Replace all of the composition-faced clutch plates and/or bands.
- Replace all of the nylon parts.
- Replace the torque converter.
- Thoroughly clean and rebuild the transmission, using new gaskets and oil filter.
Important The following steps must be completed when repairing or replacing.
Flush and flow check the transmission oil cooler using J 45096. Refer to Corporate Bulletin Number
02-07-30-052F- Automatic Transmission Oil Cooler Flush and Flow Test Essential Tool J 45096
TransFlow.
- Thoroughly inspect the engine cooling system and hoses and clean/repair as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7747
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7748
Transmission Cooler: Technical Service Bulletins A/T - Oil Cooler Flushing Frequently Asked
Questions
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 03-07-30-027
Date: June, 2003
INFORMATION
Subject: Most Frequently Asked Questions and Answers for J 45096 TransFlow Transmission Oil
Cooling System Flushing Machine
Models: 2004 and Prior Passenger Cars and Light Duty Trucks with Automatic
Transmission/Transaxle
2004 and Prior HUMMER H2
This bulletin is issued to help answer the most frequently asked questions and concerns about
essential tool J 45096.
Q: Why doesn't the machine work below 18°C (65°F)?
A: The flow characteristics of ATF at temperatures below 18°C (65°F) does not provide accurate
flow test results with the electronics used in the J
45096.
Q: Why didn't the unit come with a tank heater?
A: The vast majority of dealerships do not require a heater to keep the ATF above 18°C (65°F). As
a result, the heater was deleted as a cost-savings
measure. A tank heater, J 45096-10, is currently available from Kent-Moore if your dealership
requires it. Refer to Corporate Bulletin Number 03-07-30-002A for suggestions on warming the ATF
without using a heater blanket.
Q: Why does the machine fail new oil coolers?
A: Several reasons have been found. The most likely reason is the air pressure at the air hose
connected to the J 45096 is less than 586 kPa (85 psi).
Other reasons include a twisted hose inside the J 45096 at the bulkhead as a result of the nut
turning when the waste or supply hose was installed, the internal pressure regulator was
improperly set at the factory or a problem with the cooler lines on the vehicle. Perform the J 45096
self-test as described on pages 9 and 10 of the Operation Manual. If a problem is still detected,
refer to Troubleshooting on page 19 of the Operation Manual. If a problem still persists, contact
Kent-Moore Customer Service at 1-800-345-2233.
Q: What is the difference between steel and aluminum oil coolers?
A: The aluminum oil cooler tube is slightly thinner in construction than the steel oil cooler tube,
which affects the oil flow rate. The fitting that is
protruding out of the radiator tank easily identifies the aluminum oil cooler. Refer to the Quick
Reference card provided with the J 45096 in order to identify the proper flow rate for the aluminum
oil cooler.
Q: Why can't I use TransFlow for Allison transmission cooling Systems?
A: Validation of TransFlow is currently under development for light duty trucks equipped with the
Allison automatic transmission. TransFlow is based
on the existing MINIMUM flow rate specification through the transmission oil cooling system. The
Allison transmission oil cooling system only has MAXIMUM oil flow rates specified and J 45096
does not have the capability to test the transmission oil cooling system at the maximum oil flow rate
specification.
Q: Why doesn't GM publish a specification for auxiliary transmission oil coolers?
A: The auxiliary oil cooler used with GM vehicles does not contain an internal turbulator plate like
the radiator tank oil cooler does. Therefore, there is
no internal restriction that would affect the flow rate through the oil cooling system so a
specification for auxiliary oil cooler is not required. Keep in mind, kinks and damage to the auxiliary
cooler and lines can affect the flow rate through the system.
Q: Why did GM drop the labor time for transmission repairs?
A: The labor for flushing and flow testing the transmission oil cooling system is included with the
R&R; labor of the "K" labor operations that require
transmission removal. The time required to use the J 45096 to perform the flush and flow test is
much less than that of the J 35944-A. The warranty labor savings allowed GM to provide the J
45096 at no cost to dealerships.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7749
Q: Why didn't the machine come with the adapters to hook up to the car?
A: The J 45096 was designed to use the previously released essential cooler line adapters for the J
35944-A. All adapters are listed on page 17 of the
Operation Manual and can be ordered from Kent-Moore at 1-800-345-2233.
Q: How do I connect the J 45096 to a Catera, Prizm or a Vibe?
A: These vehicles, along with many other models, only require barbed fittings to connect to the
rubber cooler hose. These fittings are commercially
available and already found in many shops.
Q: Why didn't I receive an Operation Manual with the machine?
A: The Operation Manual was packaged in the upper portion of the shipping carton. If the shipping
carton was lifted off the base without opening the
top of the carton, the Operation Manual could have been discarded with the carton. Replacement
Operation Manual packages can be obtained from Kent-Moore Customer Service at
1-800-345-2233.
Q: Why can't I re-use the transmission fluid I use for flushing?
A: The very fine metal and clutch material debris from the transmission failure in the ATF causes
failures with the hall effect speed sensors that are used
to measure the flow rate. To avoid costly repairs, expensive filters, regular maintenance and
problems caused by a partially restricted filter, the filter was not included.
Q: What do I do if I need service on my machine?
A: Call Kent-Moore Customer Service at 1-800-345-2233. The J 45096 has a one-year warranty.
Q: Can I flush and flow engine oil coolers?
A: The engine oil cooler flow rates, the appropriate adapters and an acceptable procedure are
currently under development.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Technical Service Bulletins > A/T - Fluid Oil Cooler Flush > Page 7750
Transmission Cooler: Technical Service Bulletins A/T - Oil Cooler Flushing/Flow Check Procedures
File In Section: 07 - Transmission/Transaxle
Bulletin No.: 99-07-30-017A
Date: February, 2003
INFORMATION
Subject: Automatic Transmission Oil Cooler Flushing and Flow Check Procedures
Models: 2003 and Prior GM Light Duty Trucks 2003 HUMMER H2 with Allison(R) Automatic
Transmission (RPO M74)
This bulletin revises bulletin 99-07-30-017 to reflect the release of the new Transflow(R) J 45096
Transmission Cooling System Service Tool. The Transflow(R) Transmission Cooling System
Service Tool is to be used for all vehicles. Please discard Corporate Bulletin Number 99-07-30-017
(Section 07 - Transmission/Transaxle). Refer to Corporate Bulletin Number 02-07-30-052.
Important:
If you were sent here by the instruction booklet for the J 45096 TransFlow(R) machine, note that
the table has been moved to Corporate Bulletin Number 02-07-30-052.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Service and Repair > 4L60-E
Transmission Cooler: Service and Repair 4L60-E
Transmission Fluid Auxiliary Cooler Replacement
Removal Procedure
1. Remove the front grill assembly. 2. Place a drain pan under the vehicle. 3. Disconnect the
transmission oil cooler lines from the auxiliary cooler. 4. Remove the auxiliary oil cooler bolts (1)
and push pins (2). 5. Remove the auxiliary oil cooler from the vehicle.
Installation Procedure
1. Install the auxiliary oil cooler to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the bolts (1) and the push pins (2) that retain the auxiliary oil cooler to the radiator brace.
^ Tighten the bolts to 12 Nm (9 ft. lbs.).
3. Connect the transmission oil cooler lines to the auxiliary cooler. 4. Install the front grill assembly.
5. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Cooler,
A/T > Component Information > Service and Repair > 4L60-E > Page 7753
Transmission Cooler: Service and Repair 4L80-E
Transmission Fluid Auxiliary Cooler Replacement
Removal Procedure
1. Remove the front grill assembly. 2. Place a drain pan under the vehicle. 3. Disconnect the
transmission oil cooler lines from the auxiliary cooler. 4. Remove the auxiliary oil cooler bolts (1)
and push pins (2). 5. Remove the auxiliary oil cooler from the vehicle.
Installation Procedure
1. Install the auxiliary oil cooler to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the bolts (1) and the push pins (2) that retain the auxiliary oil cooler to the radiator brace.
^ Tighten the bolts to 12 Nm (106 inch lbs.).
3. Connect the transmission oil cooler lines to the auxiliary cooler. 4. Install the front grill assembly.
5. Fill the transmission to the proper level with Dexron III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7758
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7759
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7760
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7761
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mode
Switch, A/T > Component Information > Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 7762
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mount,
A/T > Component Information > Specifications
Transmission Mount: Specifications
4L60-E
Trans Mount to Transmission Bolt
....................................................................................................................................................... 25
Nm (18 ft. lbs.)
4L80-E
Transmission Mount to Transmission Bolts
......................................................................................................................................... 25 Nm (18
ft. lbs.) Engine Rear Mount to Transmission Bolt
............................................................................................................................................. 44 Nm
(32 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mount,
A/T > Component Information > Service and Repair > 4L60-E
Transmission Mount: Service and Repair 4L60-E
Transmission Mount Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Support the transmission with a
transmission jack. 3. Remove the two nuts securing the transmission mount to the transmission
support.
4. Raise the transmission off of the transmission support. 5. Remove the bolts (1). Raise the
transmission just enough to remove the transmission mount from the vehicle.
Installation Procedure
1. Install the transmission mount to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mount,
A/T > Component Information > Service and Repair > 4L60-E > Page 7768
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the bolts (1) that retain the transmission mount to the transmission (2WD), or transfer
case adapter (4WD).
^ For vehicles equipped with 4WD, tighten the bolts to 47 Nm (35 ft. lbs.).
^ For vehicles equipped with 2WD, tighten the bolts to 50 Nm (37 ft. lbs.).
3. Lower the transmission and install the two nuts securing the transmission mount to the
transmission support.
^ Tighten the nuts to 40 Nm (30 ft. lbs.).
4. Remove the transmission jack. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mount,
A/T > Component Information > Service and Repair > 4L60-E > Page 7769
Transmission Mount: Service and Repair 4L80-E
Transmission Mount Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Support the transmission with a
transmission jack. 3. Remove the two nuts securing the transmission mount to the transmission
support.
4. Raise the transmission off of the transmission support. 5. Remove the bolts (1). Raise the
transmission just enough to remove the transmission mount from the vehicle.
Installation Procedure
1. Install the transmission mount to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Mount,
A/T > Component Information > Service and Repair > 4L60-E > Page 7770
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the bolts (1) that retain the transmission mount to the transmission (2WD), or transfer
case adapter (4WD).
^ For vehicles equipped with 4WD, tighten the bolts to 47 Nm (35 ft. lbs.).
^ For vehicles equipped with 2WD, tighten the bolts to 50 Nm (37 ft. lbs.).
3. Lower the transmission and install the two nuts securing the transmission mount to the
transmission support.
^ Tighten the nuts to 40 Nm (30 ft. lbs.).
4. Remove the transmission jack. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 7776
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E > Page 7779
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7782
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7783
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Position
Switch/Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7784
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Pressure
Test Port, A/T > Component Information > Specifications
Transmission Pressure Test Port: Specifications
4L80-E
Oil Test Hole Plug ................................................................................................................................
............................................. 11 Nm (97 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Diagrams > 4L60-E > Page 7793
Transmission Speed Sensor: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7796
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission Speed
Sensor, A/T > Component Information > Service and Repair > 4L60-E > Page 7797
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Transmission
Temperature Sensor/Switch, A/T > Component Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > Customer Interest: > 01-07-30-038D > Sep > 06 > A/T - Poor
Performance/MIL ON/DTC P0757
Valve Body: Customer Interest A/T - Poor Performance/MIL ON/DTC P0757
Bulletin No.: 01-07-30-038D
Date: September 12, 2006
TECHNICAL
Subject: Diagnostic Trouble Code (DTC) P0757 Set, Malfunction Indicator Lamp (MIL) Illuminated,
Poor Performance of Transmission, Transmission Slipping (Clean Transmission Valve Body and
Case Oil Passages of Debris)
Models: 2007 and Prior GM Passenger Cars and Light Duty Trucks 2003-2007 HUMMER H2
2006-2007 HUMMER H3 2005-2007 Saab 9-7X
with 4L60-E/4L65-E/4L70-E Automatic Transmission (RPOs M30/M32/M70)
Supercede:
This bulletin is being revised to add the 2007 model year and the 4L70-E transmission. Also,
information has been added to Condition, Cause and Correction.
Please discard Corporate Bulletin Number 01-07-30-038C (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on any of the following conditions:
An illuminated MIL where DTC P0757 is found as a history code in the PCM or TCM.
No 3rd and 4th gear.
The transmission does not shift correctly.
The transmission feels like it shifts to Neutral or a loss of drive occurs.
The vehicle free wheels above 48 km/h (30 mph). High RPM needed to overcome the free
wheeling.
Cause
This condition may be caused by any of the following:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > Customer Interest: > 01-07-30-038D > Sep > 06 > A/T - Poor
Performance/MIL ON/DTC P0757 > Page 7809
Chips or debris plugging the bleed orifice of the 2-3 shift solenoid (367). This will cause the
transmission to stay in 2nd gear when 3rd gear is commanded and return to 1st gear when 4th
gear is commanded.
A 2-3 shift valve (368) or 2-3 shuttle valve (369) that is stuck, restricted and/or hung-up in its bore.
This condition may also be an indication of a damaged 2-4 band or 3-4 clutches. This clutch
damage may generate debris causing the 2-3 shift valve line-up to stick in the valve body bore and
set DTC P0757.
Correction
Inspect the condition of the transmission fluid for signs of overheat or a burnt odor. If either is
noted, the transmission should be disassembled for further investigation and repaired as needed.
Inspect the inside of the oil pan for signs of clutch friction material. A small amount of friction
material in the bottom of the pan is normal. If a large amount of clutch material is noted in the fluid
or bottom pan, the transmission should be disassembled for further investigation and repaired as
needed.
Inspect and clean the 2-3 shift valve (368), the 2-3 shuttle valve (369) and the valve bore of
debris/metal chips.
Inspect and clean the 2-3 shift solenoid (367B) opening of debris/metal chips. While inspecting the
2-3 shift solenoid (367B), look for a screen over the solenoid opening. If the solenoid DOES NOT
have a screen, replace the solenoid. All current GMSPO stock shift solenoids have a screen over
the solenoid opening.
If clutch debris is found, it is also very important to inspect the pressure control (PC) solenoid valve
fluid screens. Clean or replace the PC solenoid as necessary. It is also important to flush and flow
check the transmission oil cooler using J 45096. Refer to SI "Automatic Transmission Oil Cooler
Flushing and Flow Test" for the procedure.
Refer to the appropriate Service Manual for additional diagnostic information and service
procedures.
Warranty Information
For repairs performed under warranty, use the applicable published labor code and information.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-036H >
Jan > 09 > A/T Control - DTC P0756 Diagnostic Tips
Valve Body: All Technical Service Bulletins A/T Control - DTC P0756 Diagnostic Tips
INFORMATION
Bulletin No.: 01-07-30-036H
Date: January 29, 2009
Subject: Diagnostic Tips for Automatic Transmission DTC P0756, Second, Third, Fourth Gear Start
Models: 2009 and Prior GM Passenger Cars and Light Duty Trucks 2009 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
with 4L60-E, 4L65-E or 4L70E Automatic Transmission (RPOs M30, M32 or M70)
Supercede:
This bulletin is being revised to add the 2009 model year and add details regarding spacer plates.
Please discard Corporate Bulletin Number 01-07-30-036G (Section 07 - Transmission/Transaxle).
Some dealership technicians may have difficulty diagnosing DTC P0756, 2-3 Shift Valve
Performance on 4L60-E, 4L65-E or 4L70E automatic transmissions. As detailed in the Service
Manual, when the PCM detects a 4-3-3-4 shift pattern, DTC P0756 will set. Some customers may
also describe a condition of a second, third or fourth gear start that may have the same causes but
has not set this DTC yet. Below are some tips when diagnosing this DTC:
^ This is a performance code. This means that a mechanical malfunction exists.
^ This code is not set by electrical issues such as a damaged wiring harness or poor electrical
connections. Electrical problems would cause a DTC P0758, P0787 or P0788 to set.
^ The most likely cause is chips/debris plugging the filtered AFL oil at orifice # 29 on the top of the
spacer plate (48). This is a very small hole and is easily plugged by a small amount of debris. It is
important to remove the spacer plate and inspect orifice # 29 and the immediate area for the
presence of chips/debris. Also, the transmission case passage directly above this orifice and the
valve body passage directly below should be inspected and cleaned of any chips/debris. For 2003
and newer vehicles the spacer plate should be replaced. The service replacement spacer plate is a
bonded style with gaskets and solenoid filter screens bonded to the spacer plate. These screens
can help to prevent plugging of orifice # 29 caused by small debris or chips.
^ This code could be set if the 2-3 shift valve (368) were stuck or hung-up in its bore. Inspect the
2-3 shift valve (368) and the 2-3 shuttle valve (369) for free movement or damage and clean the
valves, the bore and the valve body passages.
^ This code could be set by a 2-3 shift solenoid (367b) if it were cracked, broken or leaking. Refer
to Shift Solenoid Leak Test in the appropriate Service Manual for the leak test procedure. Based on
parts return findings, a damaged or leaking shift solenoid is the least likely cause of this condition.
Simply replacing a shift solenoid will not correct this condition unless the solenoid has been found
to be cracked, broken or leaking.
It is important to also refer to the appropriate Service Manual or Service Information (SI) for further
possible causes of this condition.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning
Valve Body: All Technical Service Bulletins A/T - Valve Body Reconditioning
Bulletin No.: 07-07-30-024
Date: September 27, 2007
INFORMATION
Subject: Information on 4L60-E M30 Rear Wheel Drive Automatic Transmission Valve Body
Reconditioning, DTC P0741, P0756, P0894, Harsh 1-2 Shift
Models
The following new service information outlined in this bulletin will aid technicians in providing easy
to follow valve body reconditioning instructions and new illustrations to simplify reassembly of the
valve body. This service bulletin will also provide additional service information documents that are
related to the 4L60-E transmission.
Related Service Documents
DTC P0741 - Torque Converter Clutch (TCC) System - Stuck Off. Refer to Service Bulletin
04-07-30-041.
DTC P0756 - 2-3 Shift Solenoid Valve Performance - No First or Second Gear. Refer to Service
Bulletin 01-07-30-036F.
DTC P0894 - Transmission Component Slipping. Refer to Service Bulletin 06-07-30-007.
Harsh 1-2 Shift. Refer to Bulletin PIP3170E.
If valve body cleaning is not required, Do Not disassemble the bores unless it is necessary to verify
movement of valves.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7819
Inspection Procedure
Using the exploded views in this bulletin, inspect each bore for freedom of valve(s) movement and
evidence of debris. Pay particular attention to those valves related to the customer's concern.
Verify movement of the valves in their normal installed position. Valves may become restricted
during removal or installation. This is normal due to small tolerances between the valves and
bores.
If a valve is restricted and cannot be corrected by cleaning the valve and bore, then replace the
valve body. Describe the restricted valve on the repair order.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7820
Valve Body Spring and Bore Plug Chart (inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7821
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7822
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7823
Left Side Control Valve Body Assembly
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7824
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7825
Right Side Control Valve Body Assembly
Be sure all solenoids are installed with the electrical connectors facing the non-machined (cast)
side of the valve body; otherwise the solenoids will bind against the transmission case as the valve
body bolts are tightened and damage may occur.
Disassembly/Reassembly
If a valve is restricted by a metal burr from machining that bore, remove the valve and burr, then
inspect movement in the valve's normal position. If no
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 07-07-30-024 >
Sep > 07 > A/T - Valve Body Reconditioning > Page 7826
other debris or restrictions are found, then reassemble the valve body and install in the
transmission.
If the valve body has been contaminated with debris from another transmission component failure,
then disassemble all bores for complete cleaning of all valve body components. If possible, keep
individual bore parts separated for ease of reassembly. Use the illustrations in this bulletin for a
positive identification and location of individual parts:
Using GM Brake Clean, or equivalent, in a safe and clean environment (clean aluminum pan),
clean the valve body and dry it with compressed air. Use appropriate eye protection.
Clean individual valve body components with GM Brake Clean, or equivalent. Coat each valve with
clean ATF and reassemble in each bore. Check each valve for free movement during assembly of
each bore.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-038D >
Sep > 06 > A/T - Poor Performance/MIL ON/DTC P0757
Valve Body: All Technical Service Bulletins A/T - Poor Performance/MIL ON/DTC P0757
Bulletin No.: 01-07-30-038D
Date: September 12, 2006
TECHNICAL
Subject: Diagnostic Trouble Code (DTC) P0757 Set, Malfunction Indicator Lamp (MIL) Illuminated,
Poor Performance of Transmission, Transmission Slipping (Clean Transmission Valve Body and
Case Oil Passages of Debris)
Models: 2007 and Prior GM Passenger Cars and Light Duty Trucks 2003-2007 HUMMER H2
2006-2007 HUMMER H3 2005-2007 Saab 9-7X
with 4L60-E/4L65-E/4L70-E Automatic Transmission (RPOs M30/M32/M70)
Supercede:
This bulletin is being revised to add the 2007 model year and the 4L70-E transmission. Also,
information has been added to Condition, Cause and Correction.
Please discard Corporate Bulletin Number 01-07-30-038C (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on any of the following conditions:
An illuminated MIL where DTC P0757 is found as a history code in the PCM or TCM.
No 3rd and 4th gear.
The transmission does not shift correctly.
The transmission feels like it shifts to Neutral or a loss of drive occurs.
The vehicle free wheels above 48 km/h (30 mph). High RPM needed to overcome the free
wheeling.
Cause
This condition may be caused by any of the following:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-038D >
Sep > 06 > A/T - Poor Performance/MIL ON/DTC P0757 > Page 7831
Chips or debris plugging the bleed orifice of the 2-3 shift solenoid (367). This will cause the
transmission to stay in 2nd gear when 3rd gear is commanded and return to 1st gear when 4th
gear is commanded.
A 2-3 shift valve (368) or 2-3 shuttle valve (369) that is stuck, restricted and/or hung-up in its bore.
This condition may also be an indication of a damaged 2-4 band or 3-4 clutches. This clutch
damage may generate debris causing the 2-3 shift valve line-up to stick in the valve body bore and
set DTC P0757.
Correction
Inspect the condition of the transmission fluid for signs of overheat or a burnt odor. If either is
noted, the transmission should be disassembled for further investigation and repaired as needed.
Inspect the inside of the oil pan for signs of clutch friction material. A small amount of friction
material in the bottom of the pan is normal. If a large amount of clutch material is noted in the fluid
or bottom pan, the transmission should be disassembled for further investigation and repaired as
needed.
Inspect and clean the 2-3 shift valve (368), the 2-3 shuttle valve (369) and the valve bore of
debris/metal chips.
Inspect and clean the 2-3 shift solenoid (367B) opening of debris/metal chips. While inspecting the
2-3 shift solenoid (367B), look for a screen over the solenoid opening. If the solenoid DOES NOT
have a screen, replace the solenoid. All current GMSPO stock shift solenoids have a screen over
the solenoid opening.
If clutch debris is found, it is also very important to inspect the pressure control (PC) solenoid valve
fluid screens. Clean or replace the PC solenoid as necessary. It is also important to flush and flow
check the transmission oil cooler using J 45096. Refer to SI "Automatic Transmission Oil Cooler
Flushing and Flow Test" for the procedure.
Refer to the appropriate Service Manual for additional diagnostic information and service
procedures.
Warranty Information
For repairs performed under warranty, use the applicable published labor code and information.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-030B >
Oct > 05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis
Valve Body: All Technical Service Bulletins A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis
Bulletin No.: 01-07-30-030B
Date: October 18, 2005
INFORMATION
Subject: 4L60-E/4L65-E Automatic Transmission Diagnostic Information on Harsh 1-2 Upshift
Models: 2001-2006 GM Passenger Cars and Light Duty Trucks 2003-2006 HUMMER H2 2006
HUMMER H3 2005-2006 Saab 9-7X
with 4L60-E or 4L65-E Automatic Transmission
Supercede:
This bulletin is being revised to add model years and models. Please discard Corporate Bulletin
Number 01-07-30-030A (Section 07 - Transmission/Transaxle).
The following four conditions have been found to cause the majority of consistent, harsh 1-2 shift
comments.
^ Chips/Sediment/Debris/Contamination found in the valve body, 1-2 accumulator valve (371) bore,
may cause the 1-2 accumulator valve to stick or hang-up.
^ Chips/Sediment/Debris/Contamination found in the valve body, 4-3 sequence valve (383) bore,
may cause the 4-3 sequence valve to stick or hang-up.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-030B >
Oct > 05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7836
A cracked 1-2 accumulator piston (56) that is allowing fluid to leak by.
Mislocated/Missing valve body-to-spacer plate check balls (61).
When attempting to correct a consistent harsh 1-2 shift, the four conditions listed above should be
inspected as possible causes. It is important to also refer to the appropriate Service Manual for
further possible causes of this condition.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-030B >
Oct > 05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7837
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Valve Body: > 01-07-30-030B >
Oct > 05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7838
This diagnostic table should be used when addressing a harsh 1-2 shift concern.
Disclaimer
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 01-07-30-036H > Jan >
09 > A/T Control - DTC P0756 Diagnostic Tips
Valve Body: All Technical Service Bulletins A/T Control - DTC P0756 Diagnostic Tips
INFORMATION
Bulletin No.: 01-07-30-036H
Date: January 29, 2009
Subject: Diagnostic Tips for Automatic Transmission DTC P0756, Second, Third, Fourth Gear Start
Models: 2009 and Prior GM Passenger Cars and Light Duty Trucks 2009 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
with 4L60-E, 4L65-E or 4L70E Automatic Transmission (RPOs M30, M32 or M70)
Supercede:
This bulletin is being revised to add the 2009 model year and add details regarding spacer plates.
Please discard Corporate Bulletin Number 01-07-30-036G (Section 07 - Transmission/Transaxle).
Some dealership technicians may have difficulty diagnosing DTC P0756, 2-3 Shift Valve
Performance on 4L60-E, 4L65-E or 4L70E automatic transmissions. As detailed in the Service
Manual, when the PCM detects a 4-3-3-4 shift pattern, DTC P0756 will set. Some customers may
also describe a condition of a second, third or fourth gear start that may have the same causes but
has not set this DTC yet. Below are some tips when diagnosing this DTC:
^ This is a performance code. This means that a mechanical malfunction exists.
^ This code is not set by electrical issues such as a damaged wiring harness or poor electrical
connections. Electrical problems would cause a DTC P0758, P0787 or P0788 to set.
^ The most likely cause is chips/debris plugging the filtered AFL oil at orifice # 29 on the top of the
spacer plate (48). This is a very small hole and is easily plugged by a small amount of debris. It is
important to remove the spacer plate and inspect orifice # 29 and the immediate area for the
presence of chips/debris. Also, the transmission case passage directly above this orifice and the
valve body passage directly below should be inspected and cleaned of any chips/debris. For 2003
and newer vehicles the spacer plate should be replaced. The service replacement spacer plate is a
bonded style with gaskets and solenoid filter screens bonded to the spacer plate. These screens
can help to prevent plugging of orifice # 29 caused by small debris or chips.
^ This code could be set if the 2-3 shift valve (368) were stuck or hung-up in its bore. Inspect the
2-3 shift valve (368) and the 2-3 shuttle valve (369) for free movement or damage and clean the
valves, the bore and the valve body passages.
^ This code could be set by a 2-3 shift solenoid (367b) if it were cracked, broken or leaking. Refer
to Shift Solenoid Leak Test in the appropriate Service Manual for the leak test procedure. Based on
parts return findings, a damaged or leaking shift solenoid is the least likely cause of this condition.
Simply replacing a shift solenoid will not correct this condition unless the solenoid has been found
to be cracked, broken or leaking.
It is important to also refer to the appropriate Service Manual or Service Information (SI) for further
possible causes of this condition.
Disclaimer
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning
Valve Body: All Technical Service Bulletins A/T - Valve Body Reconditioning
Bulletin No.: 07-07-30-024
Date: September 27, 2007
INFORMATION
Subject: Information on 4L60-E M30 Rear Wheel Drive Automatic Transmission Valve Body
Reconditioning, DTC P0741, P0756, P0894, Harsh 1-2 Shift
Models
The following new service information outlined in this bulletin will aid technicians in providing easy
to follow valve body reconditioning instructions and new illustrations to simplify reassembly of the
valve body. This service bulletin will also provide additional service information documents that are
related to the 4L60-E transmission.
Related Service Documents
DTC P0741 - Torque Converter Clutch (TCC) System - Stuck Off. Refer to Service Bulletin
04-07-30-041.
DTC P0756 - 2-3 Shift Solenoid Valve Performance - No First or Second Gear. Refer to Service
Bulletin 01-07-30-036F.
DTC P0894 - Transmission Component Slipping. Refer to Service Bulletin 06-07-30-007.
Harsh 1-2 Shift. Refer to Bulletin PIP3170E.
If valve body cleaning is not required, Do Not disassemble the bores unless it is necessary to verify
movement of valves.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7848
Inspection Procedure
Using the exploded views in this bulletin, inspect each bore for freedom of valve(s) movement and
evidence of debris. Pay particular attention to those valves related to the customer's concern.
Verify movement of the valves in their normal installed position. Valves may become restricted
during removal or installation. This is normal due to small tolerances between the valves and
bores.
If a valve is restricted and cannot be corrected by cleaning the valve and bore, then replace the
valve body. Describe the restricted valve on the repair order.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7849
Valve Body Spring and Bore Plug Chart (inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7850
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7851
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7852
Left Side Control Valve Body Assembly
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7853
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7854
Right Side Control Valve Body Assembly
Be sure all solenoids are installed with the electrical connectors facing the non-machined (cast)
side of the valve body; otherwise the solenoids will bind against the transmission case as the valve
body bolts are tightened and damage may occur.
Disassembly/Reassembly
If a valve is restricted by a metal burr from machining that bore, remove the valve and burr, then
inspect movement in the valve's normal position. If no
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 07-07-30-024 > Sep >
07 > A/T - Valve Body Reconditioning > Page 7855
other debris or restrictions are found, then reassemble the valve body and install in the
transmission.
If the valve body has been contaminated with debris from another transmission component failure,
then disassemble all bores for complete cleaning of all valve body components. If possible, keep
individual bore parts separated for ease of reassembly. Use the illustrations in this bulletin for a
positive identification and location of individual parts:
Using GM Brake Clean, or equivalent, in a safe and clean environment (clean aluminum pan),
clean the valve body and dry it with compressed air. Use appropriate eye protection.
Clean individual valve body components with GM Brake Clean, or equivalent. Coat each valve with
clean ATF and reassemble in each bore. Check each valve for free movement during assembly of
each bore.
Disclaimer
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 01-07-30-030B > Oct >
05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis
Valve Body: All Technical Service Bulletins A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis
Bulletin No.: 01-07-30-030B
Date: October 18, 2005
INFORMATION
Subject: 4L60-E/4L65-E Automatic Transmission Diagnostic Information on Harsh 1-2 Upshift
Models: 2001-2006 GM Passenger Cars and Light Duty Trucks 2003-2006 HUMMER H2 2006
HUMMER H3 2005-2006 Saab 9-7X
with 4L60-E or 4L65-E Automatic Transmission
Supercede:
This bulletin is being revised to add model years and models. Please discard Corporate Bulletin
Number 01-07-30-030A (Section 07 - Transmission/Transaxle).
The following four conditions have been found to cause the majority of consistent, harsh 1-2 shift
comments.
^ Chips/Sediment/Debris/Contamination found in the valve body, 1-2 accumulator valve (371) bore,
may cause the 1-2 accumulator valve to stick or hang-up.
^ Chips/Sediment/Debris/Contamination found in the valve body, 4-3 sequence valve (383) bore,
may cause the 4-3 sequence valve to stick or hang-up.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 01-07-30-030B > Oct >
05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7860
A cracked 1-2 accumulator piston (56) that is allowing fluid to leak by.
Mislocated/Missing valve body-to-spacer plate check balls (61).
When attempting to correct a consistent harsh 1-2 shift, the four conditions listed above should be
inspected as possible causes. It is important to also refer to the appropriate Service Manual for
further possible causes of this condition.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 01-07-30-030B > Oct >
05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7861
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Valve Body: > 01-07-30-030B > Oct >
05 > A/T - 4L60-E/4L65-E Harsh 1-2 Upshift Diagnosis > Page 7862
This diagnostic table should be used when addressing a harsh 1-2 shift concern.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Technical Service Bulletins > Page 7863
Valve Body: Specifications
4L60-E
Valve Body to Case Bolt
..........................................................................................................................................................
8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Control Valve Assembly to Case
....................................................................................................................................................... 11
Nm (97 inch lbs.) Valve Body to Case/Lube Pipe
......................................................................................................................................................... 11
Nm (97 inch lbs.) Valve Body to Case/TFP .........................................................................................
.......................................................................... 11 Nm (97 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E
Valve Body: Service and Repair 4L60-E
Valve Body and Pressure Switch Replacement
Removal Procedure
1. Ensure that removal of the valve body is necessary before proceeding.
Important: The following components can be serviced without removing the valve body from the
transmission: ^
The torque converter clutch solenoid (1)
^ The pressure control solenoid (2)
^ The internal wiring harness (3)
^ The 2-3 shift solenoid (4)
^ The 1-2 shift solenoid (5)
^ The transmission fluid pressure manual valve position switch (6)
^ The 3-2 shift solenoid (7)
^ The torque converter clutch pulse width modulation (TCC PWM) solenoid (8)
2. Remove the fluid level indicator. 3. Raise the vehicle. Refer to Vehicle Lifting. 4. Remove the oil
pan, gasket, and filter.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ The transmission fluid pressure manual valve position switch (1)
^ The 1-2 shift solenoid (2)
^ The 2-3 shift solenoid (3)
^ The pressure control solenoid (4)
^ The TCC PWM solenoid (5)
^ The 3-2 shift solenoid (6)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7866
6. Remove the fluid indicator stop bracket bolt (2). 7. Remove the fluid indicator bracket (1).
8. Remove the TCC PWM solenoid retainer (2) with a small screwdriver. Rotate the solenoid (1) in
the bore, if necessary, until the flat part of the
retainer (2) is visible.
9. Remove the TCC PWM solenoid (1) in order to access the TCC solenoid retaining bolts.
10. Remove the TCC solenoid retaining bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7867
11. Remove the TCC solenoid (with O-ring seal) and wiring harness from the control valve body.
12. Reposition the harness to the side of the transmission case.
13. Remove the control valve body bolts, which retain the transmission fluid pressure switch to the
control valve body. 14. Remove the transmission fluid pressure switch.
15. Inspect the transmission fluid pressure switch for damage or debris.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7868
16. Remove the manual detent spring retaining bolt. 17. Remove the manual detent spring. 18.
Inspect the manual detent spring for cracks or damage.
Important: Keep the control valve body level when lowering it from the vehicle. This will prevent the
loss of checkballs located in the control valve body passages.
19. Remove the remaining control valve body bolts. 20. Carefully begin to lower the control valve
body down from the transmission case while simultaneously disconnecting the manual valve link.
Installation Procedure
1. Install the checkballs (1-7) in the valve body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7869
2. Install the control valve body to the transmission case while simultaneously connecting the
manual valve link to the manual valve.
3. Verify that the manual valve link (3) is installed properly to the inside detent lever (1) and the
manual valve (2).
4. Install one bolt (M6 X 1.0 X 47.5) hand tight in the center (1) of the valve body to hold it in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7870
Important: When installing bolts throughout this procedure, be sure to use the correct bolt size and
length in the correct location as specified.
5. Do not install the transmission fluid indicator stop bracket and bolt at this time. Install but do not
tighten the control valve body bolts, which retain
only the valve body directly. Each numbered bolt location corresponds to a specific bolt size and
length, as indicated by the following: ^
M6 X 1.0 X 65.0 (1)
^ M6 X 1.0 X 54.4 (2)
^ M6 X 1.0 X 47.5 (3)
^ M6 X 1.0 X 35.0 (4)
^ M8 X 1.0 X 20.0 (5)
^ M6 X 1.0 X 12.0 (6)
^ M6 X 1.0 X 18.0 (7)
6. Install the manual detent spring. 7. Install but do not tighten the manual detent spring retaining
bolt.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7871
8. Install the transmission fluid pressure switch. 9. Install but do not tighten the control valve body
bolts, which retain the transmission fluid pressure switch to the control valve body.
Notice: Refer to Fastener Notice in Service Precautions.
Notice: Torque valve body bolts in a spiral pattern starting from the center. If the bolts are torqued
at random, valve bores may be distorted and inhibit valve operation.
10. Tighten the control valve body bolts in a spiral pattern starting from the center, as indicated by
the arrows.
^ Tighten the control valve body bolts (in sequence) to 11 Nm (97 inch lbs.).
11. Ensure that the manual detent spring is aligned properly with the detent lever.
^ Tighten the manual detent spring bolt to 11 Nm (97 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7872
12. Install the TCC solenoid with a new O-ring seal to the valve body.
13. Install the TCC solenoid bolts.
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
14. Install the internal wiring harness to the valve body. The internal wiring harness has a tab (1) on
the edge of the conduit.
15. Place the tab between the valve body and the pressure switch in the location shown (2). Press
the harness into position on the valve body bolt
bosses (1, 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7873
16. Install the TCC PWM solenoid (1) to the control valve body. 17. Install the TCC PWM solenoid
retainer (2).
18. Install the transmission fluid indicator stop bracket (1) and bolt (2).
^ Tighten the transmission fluid indicator stop bracket bolt to 11 Nm (97 inch lbs.).
19. Connect the internal wiring harness electrical connectors to the following components:
^ The transmission fluid pressure manual valve position switch (1)
^ The 1-2 shift solenoid (2)
^ The 2-3 shift solenoid (3)
^ The pressure control solenoid (4)
^ The TCC PWM solenoid (5)
^ The 3-2 shift solenoid (6)
20. Install the transmission ok pan and filter. 21. Lower the vehicle. 22. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7874
Valve Body: Service and Repair 4L80-E
Valve Body and Pressure Switch Replacement
^ Tools Required J 25025 Guide Pins
- J 36350 Transjel
Removal Procedure
1. Ensure that removal of the valve body is necessary before proceeding.
Important: The following components can be serviced without removing the valve body from the
transmission: ^
The 2-3 solenoid (1)
^ The internal wiring harness (2)
^ The 1-2 shift solenoid (3)
^ The transmission fluid temperature sensor (4)
^ The transmission fluid pressure manual valve position switch (5)
^ The pressure control solenoid (6)
^ The torque converter clutch pulse width modulation (TCC PWM) solenoid (7)
2. Remove the fluid level indicator. 3. Raise the vehicle. Refer to Vehicle Lifting. 4. Remove the oil
pan, gasket, and filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7875
5. Disconnect the internal wire harness from the transmission fluid pressure (TFP) manual valve
position switch.
Important: Use care not to loose the 5 O-rings that are located between the TFP manual valve
position switch and the valve body.
6. Remove the control valve body bolts (1) that retain the (TFP) manual valve position switch (2) to
the control valve body. 7. Remove the TFP manual valve position switch. 8. Disconnect the internal
wiring harness electrical connectors from the remaining valve body electrical components.
9. Remove the lube oil pipe bolt (6) and retainer (7).
10. Remove the lube oil pipe (5). 11. Remove the bolts and remove the manual shaft detent spring
(3).
Important: Keep the control valve body level when lowering it from the vehicle. This will prevent the
loss of checkballs located in the transmission case passages.
12. Remove the remaining control valve body bolts. 13. Carefully lower the valve body down from
the transmission case. Use care not to drop the manual shaft valve. 14. Remove the control valve
assembly (2) which includes the following:
^ The accumulator housing assembly (1)
^ The control valve assembly to the spacer plate gasket
^ The spacer plate
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7876
15. Remove the manual valve (1) from the control valve body. 16. inspect the manual valve for
nicks and burrs.
17. Remove the spacer plate to case gasket (2) from the case. The gasket may stick to the spacer
plate. 18. Remove the PWM screen (1) from the case passage.
19. Remove the manual 2-1 band servo assembly (1). 20. Remove the servo piston cushion spring
(2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7877
21. Remove the manual 2-1 band servo piston pin retainer ring (4). 22. Remove the manual 2-1
band servo piston pin (1). 23. Remove the manual 2-1 band servo piston seal (2).
Important: Do not use a magnet in order to remove the checkballs. Using a magnet to remove the
checkballs may magnetize the checkballs, causing metal particles to stick.
24. Remove the eight checkballs (nine checkballs for some models).
Installation Procedure
1. Install the 8 checkballs (9 checkballs for some models) into the control valve body.
^ The checkball marked as number 2, is used on RCP, RDP, ZJP and ALP models only
^ To hold the checkballs in place, use the J 36850.
2. Install the PWM screen into the control valve body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7878
3. Install a new manual 2-1 band servo piston seal (2) onto the manual 2-1 band servo piston (3).
4. Install the manual 2-1 band servo piston pin (1) into the manual 2-1 band servo piston (3). 5.
Install the manual 2-1 band servo piston pin retainer ring (4).
6. Install the manual 2-1 band servo piston cushion spring (2).
Important: Make certain that the tapered end of the manual 2-1 band servo piston pin contacts the
manual 2-1 band.
7. Install the manual 2-1 band servo piston assembly (1).
8. Install the manual valve (1) into the control valve body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7879
9. To aid in alignment and assembly, install tool J 25025.
10. Install the control valve body gasket (6). 11. Install the control valve body assembly (5). Attach
the manual valve to the detent lever while installing the control valve body assembly.
12. Install the transmission fluid pressure manual valve position switch (2). 13. Install the
transmission fluid pressure manual valve position switch bolts (1) finger tight.
14. Tighten the bolts in the order shown to 11 Nm (97 inch lbs.). 15. Remove the J 25025.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Valve Body, A/T >
Component Information > Service and Repair > 4L60-E > Page 7880
16. Install the manual shaft detent roller and spring assembly (3) and bolts. 17. Install the two
wiring harness clips (1) and bolts (2). 18. Install the wiring harness clip (1) and bolts (2). 19. Install
the lube oil pipe (5) with the short end into the control valve body. 20. Install the lube oil pipe
retainer (7) and the bolt (6).
Notice: Refer to Fastener Notice in Service Precautions.
21. Install the control valve body bolts.
^ Tighten the bolts in the order shown to 11 Nm (97 inch lbs.).
22. Install the remaining control valve body bolts.
^ Tighten the remaining bolts to 11 Nm (97 inch lbs.).
23. Connect the internal wiring harness to the valve body electrical components 24. Install the oil
pan, gasket, and filter. 25. Lower the vehicle. 26. Fill the transmission to the proper level using
approved fluid. 27. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Wiring Harness, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Wiring Harness: > 01-07-30-002E > Sep > 05
> Electrical - A/T Stuck in 2nd/3rd Gear/MIL ON/DTC's
Wiring Harness: Customer Interest Electrical - A/T Stuck in 2nd/3rd Gear/MIL ON/DTC's
Bulletin No.: 01-07-30-002E
Date: September 23, 2005
TECHNICAL
Subject: Malfunction Indicator Lamp (MIL) On, Transmission Stuck in Second or Third Gear,
Instrument Cluster Inoperative (Verify and Repair Source of Voltage Loss In Transmission Solenoid
Power Supply Circuit)
Models: 2006 and Prior GM Passenger Cars and Light Duty Trucks 2005-2006 HUMMER H2 2006
HUMMER H3 2005-2006 Saab 9-7X
with 4L60-E, 4L65-E, 4L80-E or 4L85-E Automatic Transmission (RPOs M30, M32, M33, MT1,
MN8)
Supercede:
This bulletin is being revised to update model years, add additional models and add additional
diagnostic information. Please discard Corporate Bulletin Number 01-07-30-002D (Section 07 Transmission/Transaxle).
Condition
Some customers may comment on one or more of the following conditions:
^ The Malfunction Indicator Lamp (MIL) is ON.
^ The transmission is defaulted to second gear (4L80/85-E).
^ The transmission is defaulted to third gear (4L60/65-E).
^ The instrument cluster is inoperative.
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758,
P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the
vehicle.
Cause
The most likely cause of this condition may be a loss of voltage to the transmission solenoid power
supply circuit. This condition may also be the result of an incorrect installation of an aftermarket
electronic device such as a remote starter or alarm system.
Correction
Important:
If the vehicle is equipped with an aftermarket electronic device and the DTCs are being set when
the device is being used, verify that the appropriate fuse is being supplied battery voltage during
operation. If voltage is not present at this fuse, these DTCs will be set due to lack of voltage at the
solenoids. This condition is most likely to occur with an incorrectly installed remote starting system.
If this is the case, refer the customer to the installer of the system for corrections. ANY REPAIRS
DUE TO AFTERMARKET INSTALLATION OF ACCESSORIES IS A NON-WARRANTABLE ITEM.
1. With the ignition switch in the RUN position, test for battery voltage at the circuit fuse in the
transmission solenoid power supply circuit. Refer to the appropriate SI Document for the
transmission solenoid power supply circuit information.
2. If battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and
the transmission for possible opens.
3. If battery voltage is not present at the fuse, test for continuity between the fuse and the ignition
switch. If NO continuity is between the fuse and the ignition switch, repair the open in that circuit.
4. If you have continuity between the fuse and the ignition switch, the most likely cause is the
ignition switch. Replace the ignition switch using the appropriate Ignition Switch Replacement
procedure in SI. Refer to group number 2.188 of the parts catalog for part description and usage of
the ignition switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Wiring Harness, A/T >
Component Information > Technical Service Bulletins > Customer Interest for Wiring Harness: > 01-07-30-002E > Sep > 05
> Electrical - A/T Stuck in 2nd/3rd Gear/MIL ON/DTC's > Page 7889
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Wiring Harness, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 01-07-30-002E
> Sep > 05 > Electrical - A/T Stuck in 2nd/3rd Gear/MIL ON/DTC's
Wiring Harness: All Technical Service Bulletins Electrical - A/T Stuck in 2nd/3rd Gear/MIL
ON/DTC's
Bulletin No.: 01-07-30-002E
Date: September 23, 2005
TECHNICAL
Subject: Malfunction Indicator Lamp (MIL) On, Transmission Stuck in Second or Third Gear,
Instrument Cluster Inoperative (Verify and Repair Source of Voltage Loss In Transmission Solenoid
Power Supply Circuit)
Models: 2006 and Prior GM Passenger Cars and Light Duty Trucks 2005-2006 HUMMER H2 2006
HUMMER H3 2005-2006 Saab 9-7X
with 4L60-E, 4L65-E, 4L80-E or 4L85-E Automatic Transmission (RPOs M30, M32, M33, MT1,
MN8)
Supercede:
This bulletin is being revised to update model years, add additional models and add additional
diagnostic information. Please discard Corporate Bulletin Number 01-07-30-002D (Section 07 Transmission/Transaxle).
Condition
Some customers may comment on one or more of the following conditions:
^ The Malfunction Indicator Lamp (MIL) is ON.
^ The transmission is defaulted to second gear (4L80/85-E).
^ The transmission is defaulted to third gear (4L60/65-E).
^ The instrument cluster is inoperative.
Upon investigation, one or all of the diagnostic trouble codes (DTCs) P0740, P0753, P0758,
P0785, P0787, P0973, P0976, P1860, P2761, P2764 and P2769 may be set depending on the
vehicle.
Cause
The most likely cause of this condition may be a loss of voltage to the transmission solenoid power
supply circuit. This condition may also be the result of an incorrect installation of an aftermarket
electronic device such as a remote starter or alarm system.
Correction
Important:
If the vehicle is equipped with an aftermarket electronic device and the DTCs are being set when
the device is being used, verify that the appropriate fuse is being supplied battery voltage during
operation. If voltage is not present at this fuse, these DTCs will be set due to lack of voltage at the
solenoids. This condition is most likely to occur with an incorrectly installed remote starting system.
If this is the case, refer the customer to the installer of the system for corrections. ANY REPAIRS
DUE TO AFTERMARKET INSTALLATION OF ACCESSORIES IS A NON-WARRANTABLE ITEM.
1. With the ignition switch in the RUN position, test for battery voltage at the circuit fuse in the
transmission solenoid power supply circuit. Refer to the appropriate SI Document for the
transmission solenoid power supply circuit information.
2. If battery voltage is present at the fuse, inspect the ignition voltage circuit between the fuse and
the transmission for possible opens.
3. If battery voltage is not present at the fuse, test for continuity between the fuse and the ignition
switch. If NO continuity is between the fuse and the ignition switch, repair the open in that circuit.
4. If you have continuity between the fuse and the ignition switch, the most likely cause is the
ignition switch. Replace the ignition switch using the appropriate Ignition Switch Replacement
procedure in SI. Refer to group number 2.188 of the parts catalog for part description and usage of
the ignition switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Automatic Transmission/Transaxle > Wiring Harness, A/T >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 01-07-30-002E
> Sep > 05 > Electrical - A/T Stuck in 2nd/3rd Gear/MIL ON/DTC's > Page 7895
Warranty Information (excluding Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Warranty Information (Saab U.S. Models)
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Clutch, M/T > Clutch Hydraulic System > System Information
> Technical Service Bulletins > M/T - Hydraulic Clutch Bleeding Procedure Improvement
Clutch Hydraulic System: Technical Service Bulletins M/T - Hydraulic Clutch Bleeding Procedure
Improvement
Bulletin No.: 01-07-31-002B
Date: November 01, 2006
INFORMATION
Subject: Improved Bleeding Procedure for Hydraulic Clutch Release System
Models: 2007 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn) 2007 and
Prior Chevrolet and GMC 6-7F T-Series Medium Duty Tilt Cab Models 2007 and Prior Isuzu
F-Series Medium Duty Tilt Cab Models 2006-2007 HUMMER H3
Supercede:
This bulletin is being revised to add model years. Please discard Corporate Bulletin Number
01-07-31-002A (Section 07 - Transmission/Transaxle). This bulletin is being issued to inform
dealers of an improved procedure to aid in the ease of bleeding the clutch hydraulic system for the
above listed vehicles. This procedure can be used anytime air is introduced into the hydraulic
system. Following this procedure may also reduce the number of unnecessary parts replaced for
low clutch pedal reserve and high shift effort.
Verify that all the lines and fittings are dry and secure.
Clean the dirt and grease from the reservoir cap in order to ensure that no foreign substances enter
the system.
Remove the reservoir cap.
Fill the reservoir to the proper level with the required fluid.
Attach the J 43485 (Adapter) to the J 35555 (Mity Vac), or equivalent.
Brake fluid will deteriorate the rubber on J 43485. Use a clean shop cloth to wipe away the fluid
after each use.
Place and hold the adapter on the reservoir filler neck to ensure a tight fit. In some cases, the
adapter will fit into the reservoir opening.
Apply a vacuum of 51-68 kPa (15-20 hg) and remove the adapter.
Refill the reservoir to the proper level.
Repeat Steps 6 and 7.
If needed, refill the reservoir and continue to pull a vacuum until no more bubbles can be seen in
the reservoir or until the fluid level no longer drops.
The vehicle will move if started in gear before the Actuator Cylinder is refilled and operational. Start
the vehicle the first time in neutral to help prevent personal injury from vehicle movement and see if
the transmission will shift easily into gear.
Pump the clutch pedal until firm (to refill actuator cylinder).
Add additional fluid if needed.
Test drive vehicle to ensure proper operation.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Continuously Variable Transmission/Transaxle, CVT > Shift
Interlock, CVT > Component Information > Technical Service Bulletins > A/T - Shift Lock Control Feature Function
Shift Interlock: Technical Service Bulletins A/T - Shift Lock Control Feature Function
Bulletin No.: 03-07-30-043A
Date: May 25, 2006
INFORMATION
Subject: Information Regarding Automatic Transmission Shift Lock Control Function
Models: 2007 and Prior Passenger Cars and Trucks (Including Saturn) 2007 and Prior HUMMER
H2, H3 2005-2007 Saab 9-7X
with Automatic Transmission
Supercede:
This bulletin is being revised to add models and model years. Please discard Corporate Bulletin
Number 03-07-30-043 (Section 07 - Transmission/Transaxle). This bulletin is being issued to better
explain how the Automatic Transmission Shift Lock Control (formerly known as Brake Transmission
Shift Interlock (BTSI)) feature is intended to operate. Revised wording regarding the shift lock
control system began appearing in the Owner Manuals beginning with the 2004 model year.
The shift lock control feature was intended to prevent drivers from shifting out of Park with the
vehicle running without the brakes applied. However, if the ignition switch is in the Accessory
(ACC) position, it may be possible on some vehicles to move the shift lever out of Park WITHOUT
first activating the brake.
The shift lock control system is ONLY active when the ignition switch is in the RUN or ON position.
This means that when the ignition switch is in the RUN or ON position, the shift lever cannot be
moved out of the Park position without activating the brake.
Some owners may feel that the shift lock control system prevents an unattended child from moving
the vehicle. Please stress to owners, as stated in the Owner Manual, that children should NEVER
be left unattended in a vehicle, even if the ignition key has been removed from the vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Carrier > Carrier Bearings
> Component Information > Technical Service Bulletins > Customer Interest for Carrier Bearings: > 09-04-19-001 > Apr > 09
> Drivetrain - Whine or Click Type Noises from Front Axle
Carrier Bearings: Customer Interest Drivetrain - Whine or Click Type Noises from Front Axle
TECHNICAL
Bulletin No.: 09-04-19-001
Date: April 28, 2009
Subject: Whine or Click Type Noises from Front Axle/New Design Front Axle Side Bearing
Adjusters (Inspect/Replace with New Lock Rings)
Models:
2002-2009 Cadillac Escalade, Escalade ESV, Escalade EXT 2002-2009 Chevrolet Avalanche,
Silverado, Suburban, Tahoe 2002-2009 GMC Sierra, Yukon, Yukon XL All Equipped with 8.25"
Front Axle
Condition
Some customers may comment about whine or click type noises from the front axle. Upon further
investigation, disassembly of the front differential may reveal chipped pinion or ring gear teeth.
Cause
This condition may be caused by an oversize front bearing side adjuster lock ring allowing the
adjuster to move.
New Design Lock Adjusters Vs Old Design T-Lock Adjusters
Note
Front axle housings for old-style (Classic - GMT800) and new-style (GMT900) vehicles are not
interchangeable.
The new design eliminates the side bearing adjusters movement. The lock adjusters are retained
by a pressed in lock ring that maintains the adjuster setting for backlash and side bearing preload.
All front axle housings for all model years will use the new design adjusters, and use the new lock
ring.
The t-lock adjusters are still available, but if a housing replacement is needed, it is necessary to
order the lock ring style housing, two of the new adjusters and two of the lock rings. Part numbers
are available through the GM Parts catalog.
A newly designed 8.25" front axle is in production. The new design eliminates the t-lock side
bearing adjusters. The new adjusters are retained by a pressed in lock ring that maintains the
adjuster setting for backlash and side bearing preload. This design was phased into production
during September, 2006. As a result, in the 2007 model year, both old-style (Classic - GMT800)
and new-style (GMT900) vehicles built before the change have the t-lock design adjusters, and
both types of vehicles built after the change have the lock ring design adjusters.
Correction
If no damage is visible and the concern was a whine or click noise, follow the inspect procedure in
this bulletin and replace the lock ring. Complete assembly replacement is not necessary if an
oversized slipping lock ring was found.
Important The bearing adjuster lock rings are not reusable.
Inspect New Replacement Part Prior to Installation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Carrier > Carrier Bearings
> Component Information > Technical Service Bulletins > Customer Interest for Carrier Bearings: > 09-04-19-001 > Apr > 09
> Drivetrain - Whine or Click Type Noises from Front Axle > Page 7916
Replace the side bearing adjuster lock ring and refer to SI for adjustment. When replacing the side
bearing adjuster lock ring, inspect the old locking ring and make sure there are vertical lines in the
outer and inner diameter of the ring (1). Next inspect and make sure there is tension when the
locking rings are installed. If the locking ring rotates freely around the adjuster, do not use the
locking ring. Replace with a new locking ring and make the same inspection.
Oversize Lock Rings-Do Not Use
The new lock rings will not have any vertical lines (inner or outer). They are imprinted during install.
If vertical lines are shown (1), DO NOT USE.
Parts Information
Refer to GM Parts Catalog.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Carrier > Carrier Bearings
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Carrier Bearings: >
09-04-19-001 > Apr > 09 > Drivetrain - Whine or Click Type Noises from Front Axle
Carrier Bearings: All Technical Service Bulletins Drivetrain - Whine or Click Type Noises from Front
Axle
TECHNICAL
Bulletin No.: 09-04-19-001
Date: April 28, 2009
Subject: Whine or Click Type Noises from Front Axle/New Design Front Axle Side Bearing
Adjusters (Inspect/Replace with New Lock Rings)
Models:
2002-2009 Cadillac Escalade, Escalade ESV, Escalade EXT 2002-2009 Chevrolet Avalanche,
Silverado, Suburban, Tahoe 2002-2009 GMC Sierra, Yukon, Yukon XL All Equipped with 8.25"
Front Axle
Condition
Some customers may comment about whine or click type noises from the front axle. Upon further
investigation, disassembly of the front differential may reveal chipped pinion or ring gear teeth.
Cause
This condition may be caused by an oversize front bearing side adjuster lock ring allowing the
adjuster to move.
New Design Lock Adjusters Vs Old Design T-Lock Adjusters
Note
Front axle housings for old-style (Classic - GMT800) and new-style (GMT900) vehicles are not
interchangeable.
The new design eliminates the side bearing adjusters movement. The lock adjusters are retained
by a pressed in lock ring that maintains the adjuster setting for backlash and side bearing preload.
All front axle housings for all model years will use the new design adjusters, and use the new lock
ring.
The t-lock adjusters are still available, but if a housing replacement is needed, it is necessary to
order the lock ring style housing, two of the new adjusters and two of the lock rings. Part numbers
are available through the GM Parts catalog.
A newly designed 8.25" front axle is in production. The new design eliminates the t-lock side
bearing adjusters. The new adjusters are retained by a pressed in lock ring that maintains the
adjuster setting for backlash and side bearing preload. This design was phased into production
during September, 2006. As a result, in the 2007 model year, both old-style (Classic - GMT800)
and new-style (GMT900) vehicles built before the change have the t-lock design adjusters, and
both types of vehicles built after the change have the lock ring design adjusters.
Correction
If no damage is visible and the concern was a whine or click noise, follow the inspect procedure in
this bulletin and replace the lock ring. Complete assembly replacement is not necessary if an
oversized slipping lock ring was found.
Important The bearing adjuster lock rings are not reusable.
Inspect New Replacement Part Prior to Installation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Carrier > Carrier Bearings
> Component Information > Technical Service Bulletins > All Technical Service Bulletins for Carrier Bearings: >
09-04-19-001 > Apr > 09 > Drivetrain - Whine or Click Type Noises from Front Axle > Page 7922
Replace the side bearing adjuster lock ring and refer to SI for adjustment. When replacing the side
bearing adjuster lock ring, inspect the old locking ring and make sure there are vertical lines in the
outer and inner diameter of the ring (1). Next inspect and make sure there is tension when the
locking rings are installed. If the locking ring rotates freely around the adjuster, do not use the
locking ring. Replace with a new locking ring and make the same inspection.
Oversize Lock Rings-Do Not Use
The new lock rings will not have any vertical lines (inner or outer). They are imprinted during install.
If vertical lines are shown (1), DO NOT USE.
Parts Information
Refer to GM Parts Catalog.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Case > Component
Information > Specifications
Differential Case: Specifications
Rear Drive Axle - Locking/Limited Slip Rear Axle
Differential Case Screws (10.5" axle)
................................................................................................................................................... 17
Nm (13 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Cover > Component
Information > Specifications
Differential Cover: Specifications
Rear Drive Axle
Differential Housing Cover Bolts (All Axles)
...................................................................................................................................... 40 Nm (30 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Axle Housing >
Component Information > Technical Service Bulletins > Customer Interest for Differential Axle Housing: > 03-04-19-003 >
Jul > 03 > Drivetrain - Fluid Leak From Front of Vehicle
Differential Axle Housing: Customer Interest Drivetrain - Fluid Leak From Front of Vehicle
Bulletin No.: 03-04-19-003
Date: July 30, 2003
ADVANCED SERVICE INFORMATION
Subject: Fluid Leak From Front of Vehicle (Add Teflon(R) Tape To Front Axle Vent/Plug Threads)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2003 Cadillac Escalade ESV 2002-2003
Chevrolet Avalanche, Silverado, Suburban, Tahoe 2002-2003 GMC Denali, Denali XL, Sierra,
Yukon, Yukon XL 2003 HUMMER H2 with All Wheel Drive or Four Wheel Drive Condition
Some customers may comment on a fluid leak from the front of the vehicle. Diagnosis may lead to
a concern of an axle fluid leak from the front axle vent connector assembly (or plug in an H2). In
some cases, the vent/plug connector may be finger tight, or separated from the axle housing.
Cause
Some vent/plug connectors may exhibit a shrinkage after installation into the axle assembly, which
occurs for a time during thermal cycling until it becomes dimensionally stable.
Correction
Replacing the vent/plug connector may not repair the vehicle in some cases because the new
piece may also shrink. A vent connector with a new material that will not exhibit this condition will
enter production in the 4th quarter of 2003. Until the new part number vent/plug connector
assembly is available from SPO, follow the recommended procedure below. This bulletin will be
revised when the new part number becomes available.
Procedure
Reseal the vent/plug connector assembly with Teflon(R) tape following these steps:
1. Remove the vent/plug connector from the axle assembly.
2. Remove the 0-ring from the vent/plug connector. Inspect the 0-ring for wear or cracks.
3. Wipe away any excess oil and debris with a clean cloth.
4. Mark the vent/plug connector on the flange in order to identify the starting point of the Teflon(R)
tape.
Important:
^ DO NOT tape the inner-most threads of the vent/plug. Excessive Teflon(R) tape may enter the
front axle assembly possibly causing a seal leak.
^ DO NOT USE RTV Silicone on the vent/plug.
5. Wrap Teflon(R) tape three times around the vent/plug connector threads in a clockwise direction
relative to the vane/oil side of the vent. Start and stop at the mark from step 4.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Axle Housing >
Component Information > Technical Service Bulletins > Customer Interest for Differential Axle Housing: > 03-04-19-003 >
Jul > 03 > Drivetrain - Fluid Leak From Front of Vehicle > Page 7937
6. Trim the excess Teflon(R) tape from the inner-most threads. Excessive Teflon(R) tape may enter
the front axle assembly possibly causing a seal leak.
7. Reinstall the vent/plug connector 0-ring.
Important:
Do not over or under-tighten from this specification or a leak may occur.
8. Install the vent/plug connector back into the axle assembly.
Tighten
Tighten the vent/plug connector to 15-20 N.m (11-14 lb ft).
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Axle Housing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Differential Axle Housing: >
03-04-19-003 > Jul > 03 > Drivetrain - Fluid Leak From Front of Vehicle
Differential Axle Housing: All Technical Service Bulletins Drivetrain - Fluid Leak From Front of
Vehicle
Bulletin No.: 03-04-19-003
Date: July 30, 2003
ADVANCED SERVICE INFORMATION
Subject: Fluid Leak From Front of Vehicle (Add Teflon(R) Tape To Front Axle Vent/Plug Threads)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2003 Cadillac Escalade ESV 2002-2003
Chevrolet Avalanche, Silverado, Suburban, Tahoe 2002-2003 GMC Denali, Denali XL, Sierra,
Yukon, Yukon XL 2003 HUMMER H2 with All Wheel Drive or Four Wheel Drive Condition
Some customers may comment on a fluid leak from the front of the vehicle. Diagnosis may lead to
a concern of an axle fluid leak from the front axle vent connector assembly (or plug in an H2). In
some cases, the vent/plug connector may be finger tight, or separated from the axle housing.
Cause
Some vent/plug connectors may exhibit a shrinkage after installation into the axle assembly, which
occurs for a time during thermal cycling until it becomes dimensionally stable.
Correction
Replacing the vent/plug connector may not repair the vehicle in some cases because the new
piece may also shrink. A vent connector with a new material that will not exhibit this condition will
enter production in the 4th quarter of 2003. Until the new part number vent/plug connector
assembly is available from SPO, follow the recommended procedure below. This bulletin will be
revised when the new part number becomes available.
Procedure
Reseal the vent/plug connector assembly with Teflon(R) tape following these steps:
1. Remove the vent/plug connector from the axle assembly.
2. Remove the 0-ring from the vent/plug connector. Inspect the 0-ring for wear or cracks.
3. Wipe away any excess oil and debris with a clean cloth.
4. Mark the vent/plug connector on the flange in order to identify the starting point of the Teflon(R)
tape.
Important:
^ DO NOT tape the inner-most threads of the vent/plug. Excessive Teflon(R) tape may enter the
front axle assembly possibly causing a seal leak.
^ DO NOT USE RTV Silicone on the vent/plug.
5. Wrap Teflon(R) tape three times around the vent/plug connector threads in a clockwise direction
relative to the vane/oil side of the vent. Start and stop at the mark from step 4.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Axle Housing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Differential Axle Housing: >
03-04-19-003 > Jul > 03 > Drivetrain - Fluid Leak From Front of Vehicle > Page 7943
6. Trim the excess Teflon(R) tape from the inner-most threads. Excessive Teflon(R) tape may enter
the front axle assembly possibly causing a seal leak.
7. Reinstall the vent/plug connector 0-ring.
Important:
Do not over or under-tighten from this specification or a leak may occur.
8. Install the vent/plug connector back into the axle assembly.
Tighten
Tighten the vent/plug connector to 15-20 N.m (11-14 lb ft).
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Differential Axle Housing >
Component Information > Technical Service Bulletins > Page 7944
Differential Axle Housing: Specifications
Front Drive Axle
Inner Axle Shaft Housing to Bracket Nuts
......................................................................................................................................... 100 Nm (75
ft. lbs.) Inner Axle Shaft Housing to Differential Carrier Assembly Bolts .............................................
........................................................................................................................................................ 40
Nm (30 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Drain Plug, Differential > Component
Information > Specifications
Drain Plug: Specifications
Front Drive Axle
Plug, Drain and Fill ..............................................................................................................................
................................................ 33 Nm (24 ft. lbs.)
Rear Drive Axle
Drain Plug (All Axles) ...........................................................................................................................
............................................... 33 Nm (24 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Fill Plug, Differential > Component
Information > Specifications
Fill Plug: Specifications
Front Drive Axle
Plug, Drain and Fill ..............................................................................................................................
................................................ 33 Nm (24 ft. lbs.)
Rear Drive Axle
Fill Plug (All Axles) ...............................................................................................................................
.............................................. 33 Nm (24 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Fluid - Differential > Component
Information > Technical Service Bulletins > Drivetrain - Front Drive Axle Lubrication Update
Fluid - Differential: Technical Service Bulletins Drivetrain - Front Drive Axle Lubrication Update
Bulletin No.: 05-00-90-010
Date: December 07, 2005
SERVICE MANUAL UPDATE
Subject: Revised Front Drive Axle Carrier Lubricant Information
Models: 1999-2005 Light Duty Trucks 2003-2005 HUMMER H2 2005 Saab 9-7X
with Four-Wheel or All-Wheel Drive and
Separate Front Drive Axle Carriers
This bulletin is being issued to revise the front drive axle carrier lubricant specification in the
Maintenance and Lubrication and the Front Drive Axle sub-sections of the Service Manual. Please
replace the current information in the Service Manual with the following information.
The information has been updated within SI. If you are using a paper version of this Service
Manual, please make a reference to this bulletin on the affected page.
This information also updates the information found in the Owner Manual.
Important:
Front drive axle carriers do not require periodic lubricant replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Fluid - Differential > Component
Information > Technical Service Bulletins > Drivetrain - Front Drive Axle Lubrication Update > Page 7955
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Fluid - Differential > Component
Information > Specifications > Capacity Specifications
Fluid - Differential: Capacity Specifications
Differential Oil Capacity
Front Drive Axle (8.25") .......................................................................................................................
..................................................... 1.66 L (1.75 qts.) Front Drive Axle (9.25") .....................................
....................................................................................................................................... 1.73 L (1.83
qts.) Rear Drive Axle (8.6") ..................................................................................................................
............................................................. 2.28 L (2.41 qts.) Rear Drive Axle (9.5") ...............................
.................................................................................................................................................. 2.6 L
(2.75 qts.) Rear Drive Axle (10.5") ......................................................................................................
......................................................................... 2.6 L (2.75 qts.) Rear Drive Axle (11.5") ...................
..........................................................................................................................................................
3.62 L (3.83 qts.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Fluid - Differential > Component
Information > Specifications > Capacity Specifications > Page 7958
Fluid - Differential: Fluid Type Specifications
Differential Fluid Type
Differential Fluid Type
Front (S4WD) Grade ...........................................................................................................................
.................................................................................................. GL-5 Viscosity ..................................
..............................................................................................................................................................
................... 80W-90 Front (F4WD) Grade ..........................................................................................
............................................................................................................................. Synthetic Viscosity .
..............................................................................................................................................................
.................................................... 75W-90 Rear Grade .......................................................................
................................................................................................................................................
Synthetic Viscosity ...............................................................................................................................
.................................................................................... 75W-90
Front Differential
Differential Fluid Type
The content of this article reflects the changes identified in TSB number 05-00-90-010 dated
December 07, 2005.
1999-2004 7.25 Inch (Blazer, Jimmy, S-10, Sonoma, Astro, Safari) Grade ........................................
..............................................................................................................................................................
....................... GL-5 Viscosity .............................................................................................................
...................................................................................................... 80W-90 2002-2005 7.25 Inch
(Trailblazer, Envoy, Bravada, Rainier Grade .......................................................................................
................................................................................................................................ Synthetic
Viscosity ..............................................................................................................................................
..................................................................... 75W-90 8.25 Inch With Selectable 4WD Grade ............
..............................................................................................................................................................
................................................... GL-5 Viscosity .................................................................................
.................................................................................................................................. 80W-90 8.25
Inch With AWD Grade .........................................................................................................................
.............................................................................................. Synthetic Viscosity ................................
..............................................................................................................................................................
..................... 75W-90 1999-2001 9.25 Inch Grade .............................................................................
................................................................................................................................................ GL-5
Viscosity ..............................................................................................................................................
..................................................................... 80W-90 2002-2005 9.25 Inch Grade .............................
..............................................................................................................................................................
............................ Synthetic Viscosity ..................................................................................................
................................................................................................................. 75W-90
Front Drive Axle
Differential Fluid Type
The content of this article reflects the changes identified in TSB number 05-00-90-010 dated
December 07, 2005.
1999-2004 7.25 Inch (Blazer, Jimmy, S-10, Sonoma, Astro, Safari) Grade ........................................
..............................................................................................................................................................
....................... GL-5 Viscosity .............................................................................................................
...................................................................................................... 80W-90 2002-2005 7.25 Inch
(Trailblazer, Envoy, Bravada, Rainier Grade .......................................................................................
................................................................................................................................ Synthetic
Viscosity ..............................................................................................................................................
..................................................................... 75W-90 8.25 Inch With Selectable 4WD Grade ............
..............................................................................................................................................................
................................................... GL-5 Viscosity .................................................................................
.................................................................................................................................. 80W-90 8.25
Inch With AWD Grade .........................................................................................................................
.............................................................................................. Synthetic Viscosity ................................
..............................................................................................................................................................
..................... 75W-90 1999-2001 9.25 Inch Grade .............................................................................
................................................................................................................................................ GL-5
Viscosity ..............................................................................................................................................
..................................................................... 80W-90 2002-2005 9.25 Inch Grade .............................
..............................................................................................................................................................
............................ Synthetic Viscosity ..................................................................................................
................................................................................................................. 75W-90
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Pinion Bearing, Differential >
Component Information > Specifications
Pinion Bearing: Specifications
Front Drive Axle
Pinion bearing preload (New Bearings)
................................................................................................................................... 1.7-3.4 Nm
(15-30 in.lbs.) Pinion bearing preload (Used Bearings)
.................................................................................................................................... 1.1-2.8 Nm
(10-25 in.lbs.) Pinion bearing and differential case bearing preload (New Bearings) ..........................
............................................................................................................................................... 3.4-6.2
Nm (30-55 in.lbs.) Pinion bearing and differential case bearing preload (Used Bearings) ..................
......................................................................................................................................................
2.8-5.6 Nm (25-50 in.lbs.)
Rear Drive Axle
Bearing Cap Bolts (8.6" Axle)
..............................................................................................................................................................
75 Nm (55 ft. lbs.) Bearing Cap Bolts (9.5" Axle)
..............................................................................................................................................................
85 Nm (63 ft. lbs.) Bearing Cap Bolts (10.5" Axle)
.........................................................................................................................................................
185 Nm (136 ft. lbs.) Differential Bearing Adjuster Nut Lock Bolt (9.5" Axle)
..................................................................................................................... 26 Nm (19 ft. lbs.)
Differential Bearing Adjuster Nut Lock Bolt (10.5" Axle)
................................................................................................................... 27 Nm (20 ft. lbs.) Pinion
Bearing Cage Bolts (10.5" Axle)
............................................................................................................................................... 88 Nm
(65 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Pinion Flange, Differential >
Component Information > Specifications
Pinion Flange: Specifications
Rear Drive Axle
Axle Flange Bolts (10.5" Axle)
........................................................................................................................................................
156 Nm (115 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Differential Assembly > Ring Gear, Differential > Component
Information > Specifications
Ring Gear: Specifications
Front Drive Axle
Ring Gear Bolts ...................................................................................................................................
............................................... 120 Nm (88 ft. lbs.)
Rear Drive Axle
Ring Gear Bolts (8.6" Axle) .................................................................................................................
.............................................. 120 Nm (89 ft. lbs.) Ring Gear Bolts (9.5" Axle)
.............................................................................................................................................................
140 Nm (103 ft. lbs.) Ring Gear Bolts (10.5" Axle)
...........................................................................................................................................................
165 Nm (122 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Bearing >
Component Information > Adjustments
Axle Bearing: Adjustments
REVISED WHEEL BEARING ADJ. (10.5" & 11.5" RING GEAR)
Bulletin No.: 02-04-20-002
Date: May, 2002
IMPORTANT:
Ensure the brakes are fully released and do not drag. ^
Pull or push the tire at the top back and forth in order to test the wheel bearing play.
^ Use a pry bar under the tire as an alternative.
^ If the wheel bearing adjustment is correct, the movement will be barely noticeable.
^ If the movement is excessive, adjust the bearings.
Adjustment Procedure Tools Required J 2222-C Wheel Bearing Nut Wrench 1. Raise the vehicle.
2. Remove the axle shaft.
3. Remove the hub adjuster nut retaining ring.
4. Remove the adjuster nut lock key.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Bearing >
Component Information > Adjustments > Page 7972
5. Tighten the wheel bearing adjusting nut using the J 2222-C.
^ Rotate the hub in the opposite direction to the way the adjuster nut is turning.
^ Ensure the inner bearing and the seal seats against the spindle shoulder.
TIGHTEN
^ Adjusting nut to 70 Nm (52.0 lb ft).
6. Turn the adjusting nut counterclockwise until the nut is loose using the J 2222-C. 7. Turn the
adjusting nut clockwise until the nut contacts the bearing cone. Torque on the nut must be zero to
finger tight.
8. Insert the adjusting nut lock key into the keyway using one of the following procedures:
^ If the adjusting nut slot is in alignment with the keyway in the axle spindle, insert the adjusting nut
lock key into the keyway in the axle spindle.
IMPORTANT:
Do not turn the adjusting nut more than one slot counterclockwise in order to align the adjusting nut
slot with the keyway in the axle spindle.
^ If the adjusting nut slot is not aligned with the keyway in the axle spindle, turn the adjusting nut
counterclockwise until the adjusting nut slot is in alignment with the keyway in the axle spindle and
insert the adjusting nut lock key.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Bearing >
Component Information > Adjustments > Page 7973
9. Install the retaining ring.
10. Install the axle shaft. 11. Inspect the lubricant level and add, if necessary. 12. Lower the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service
Constant Velocity Joint: Technical Service Bulletins Drivetrain - Revised Inner Drive Axle Joint
Service
File In Section: 04 - Driveline Axle
Bulletin No.: 03-04-18-003
Date: June, 2003
SERVICE MANUAL UPDATE
Subject: Revised Wheel Drive Shaft Inner Joint and Seal Replacement
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2001-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2001-2003 GMC Sierra, Suburban, Yukon, Yukon XL 2003
HUMMER H2 with Four Wheel Drive
This bulletin is being issued to revise the Wheel Drive Shaft Inner Joint and Seal Replacement
procedure in the Rear Wheel Drive Shafts sub-section of the Service Manual. Please replace the
current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Wheel Drive Shaft Inner Joint and Seal Replacement
Tools Required
^ J 35910 Seal Clamp Tool
^ J 36652 Drive Axle Clamp Swage Tool
^ J 36652-98 Axle Swage Tool
Disassembly Procedure
Important:
Use caution when using the hand grinder by the tripot housing (1).
1. Use a hand grinder in order to cut through the swage ring (2).
2. Remove the tripot housing (1) from the halfshaft.
3. Wipe the grease off of the housing (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7979
4. Thoroughly degrease the tripot housing (1).
5. Allow the tripot housing (1) to dry prior to assembly.
6. Using side cutters, remove the small boot retaining clamp.
7. Remove the following items from the halfshaft bar:
7.1. The spacer ring (1)
7.2. The tripot spider assembly (2)
7.3. The tripot boot (3)
8. Clean the halfshaft bar (4). Use a wire brush in order to remove any rust in the seal mounting
area (grooves).
9. Inspect the needle rollers, needle bearings, and bearings. Check the tripot housing for unusual
wear, cracks, or other damage. Replace any damaged parts with the appropriate service kit.
Assembly Procedure
1. Place the new small seal clamp (2) onto the small end of the joint seal (1). Compress the joint
seal (1) and small seal clamp (2) onto the halfshaft bar.
2. Position the small end of the joint seal (1) into the joint seal groove (3) on the halfshaft bar.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7980
Notice:
Refer to Fastener Notice in Cautions and Notices.
3. Secure the small seal clamp (1) with J 35910 (or equivalent), a breaker bar, and a torque wrench
Tighten
Tighten the small seal clamp (1) to 136 N.m (100 lb ft).
4. Check the gap dimension on the clamp ear. Continue tightening until the gap dimension is
reached.
Important:
Assemble the tripot joint with the convolute retainer in the correct position, as illustrated.
5. Install the convolute retainer tool over the inboard joint seal, being sure to capture the following
convolutions:
^ 2-5 for the 1500 model (except 1500HD)
^ 2-4 for the 1500HD, 2500, 3500, and HUMMER H2 models.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7981
6. Install the tripot spider assembly (3) onto the halfshaft bar (2).
7. Install the spacer ring (1) in the groove at the end of the halfshaft bar (2).
8. Pack the tripot seal (4) and the tripot housing (1) with the grease supplied in the kit. The amount
of grease supplied in this kit has been pre-measured for this application.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7982
9. Reassemble the tripot housing and the tripot seal using the following procedure:
9.1. Pinch the swage ring (2) slightly by hand in order to distort it into an oval shape.
9.2. Slide the distorted swage ring (2) over the large diameter of the seal.
9.3. Place the tripot housing over the spider assembly.
9.4. Install the seal onto the tripot housing.
9.5. Align the tripot seal (1), with the swage ring (2) in place, over the flat area on the tripot housing
(3).
10. For the 1500 models (except 1500HD), assemble the bolts and the support plate to the base of
the J-36652-01 and secure the base in a vise.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7983
11. For the 1500HD, 2500, 3500, and HUMMER H2 models, assemble the bolts and the support
plate to the base of the J 36652-98 and secure the base in a vise.
12. Inspect the inboard stroke position.
^ Use measurement A for the 1500 models (except 1500HD).
^ Use measurement B for the 1500HD, 2500, 3500, and HUMMER H2 models.
13. Position the inboard end (tripot end) of the halfshaft assembly into the base of the J-36652-01
for the 1500 models (except 1500HD) or J 36652-98 for the 1500HD, 2500, 3500 and HUMMER
H2 models.
14. Install the top half of the J-36652-01 for the 1500 models (except 1500HD) or J 36652-98 for
the 1500HD, 2500, 3500 and HUMMER H2 models.
15. Align the swage ring (2) and the swage ring clamp.
16. Insert the bolts.
Tighten
Hand tighten the bolts until the bolts are snug.
Important:
Align the following during this procedure:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle Joint
Service > Page 7984
^ The tripot boot (3)
^ The tripot housing (1)
^ The swage ring (2)
Tighten
Tighten each bolt 180 degrees at a time. Alternate between the bolts until both sides of the top half
of the tool touch the bottom half.
17. Loosen the bolts and remove the halfshaft assembly from the tool.
18. Remove the convolute retainer tool from the boot.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement
Constant Velocity Joint: Service and Repair Wheel Drive Shaft Inner Joint and Seal Replacement
Wheel Drive Shaft Inner Joint and Seal Replacement
^ Tools Required J 8059 Snap Ring Pliers
- J 35910 Seal Clamp Tool
- J 36652 Split Plate Swage Clamp
Disassembly Procedure
Notice: With the removal of the wheel drive shaft for any reason, the transmission sealing surface
(the tripot male/female shank of the joint) should be inspected for corrosion. If corrosion is evident,
the surface should be cleaned with 320 grit cloth or equivalent in a rotational motion only. Do not
clean with an oscillating motion. Transmission fluid may be used to clean off any remaining debris
and the joint wiped dry before installation. Corrosion on the joint sealing surface may damage the
transmission seals and cause a fluid leak.
Important: Use caution when using the hand grinder by the tripot housing (1).
1. Use a hand grinder in order to cut through the swage ring (2). 2. Remove the tripot housing (1)
from the halfshaft. 3. Wipe the grease off of the tripot assembly roller bearings and the tripot
housing (1). 4. Thoroughly degrease the tripot housing (1). 5. Allow the tripot housing (1) to dry
prior to assembly.
Important: Handle the tripot spider assembly with care. Tripot balls and needle rollers may separate
from the spider trunnion if the tripot balls and needle rollers are not handled carefully. Use side
cutters to cut away the small seal clamp.
6. Compress the tripot seal up the halfshaft, away from the tripot spider assembly toward the
outboard (CV joint assembly) end of the halfshaft. 7. Spread the spider spacer ring (2) with J 8059
(or equivalent).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7987
8. Remove the following items from the halfshaft bar:
8.1. The spacer ring (1)
8.2. The spider assembly (2)
8.3. The tripot seal (3)
9. Clean the halfshaft bar (4). Use a wire brush in order to remove any rust in the seal mounting
area (grooves).
10. Inspect the needle rollers, needle bearings, and trunnion. Check the tripot housing for unusual
wear, cracks, or other damage. Replace any
damaged parts with the appropriate service kit.
Assembly Procedure
1. Place the new small seal clamp (2) onto the small end of the joint seal (1). Compress the joint
seal (1) and small seal clamp (2) onto the halfshaft
bar.
2. Position the small end of the joint seal (1) into the joint seal groove (3) on the halfshaft bar.
Notice: Refer to Fastener Notice in Service Precautions.
3. Secure the small seal clamp (1) with J 35910 (or equivalent), a breaker bar, and a torque
wrench.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7988
^ Tighten the small seal clamp (1) to 136 Nm (100 ft. lbs.).
4. Check the gap dimension on the clamp ear. Continue tightening until the gap dimension is
reached.
Important: Assemble the tripot joint with the convolute retainer in the correct position, as illustrated.
5. Install the convolute retainer tool over the inboard joint seal, being sure to capture the following
convolutions:
^ 2-5 for the K1500 model.
^ 2-4 for the K2500, K3500, and Hummer 2 models.
6. Install the tripot spider assembly (3) onto the halfshaft bar (2). 7. Install the spacer ring (1) in the
groove at the end of the halfshaft bar (2).
8. Pack the tripot seal (4) and the tripot housing (1) with the grease supplied in the kit. The amount
of grease supplied in this kit has been
pre-measured for this application.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7989
9. Reassemble the tripot housing and the tripot seal using the following procedure:
9.1. Pinch the swage ring (2) slightly by hand in order to distort it into an oval shape.
9.2. Slide the distorted swage ring (2) over the large diameter of the seal.
9.3. Place the tripot housing over the spider assembly.
9.4. Install the seal onto the tripot housing.
9.5. Align the tripot seal (1), with the swage ring (2) in place, over the flat area on the tripot housing
(3).
10. Mount the base of J 36652 in a vise.
11. Check the inboard stroke position.
^ Use measurement A for the K1500 models.
^ Use measurement B for the K2500, K3500, and Hummer 2 models.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7990
12. Position the inboard end (tripot end) of the halfshaft assembly into the base of J 36652. 13.
Install the top half of J 36652. 14. Align the swage ring (2) and the swage ring clamp. 15. Insert the
bolts.
^ Hand tighten the bolts in J 36652 until the bolts are snug.
Important: Align the following during this procedure: ^
The tripot seal (3)
^ The housing (1)
^ The swage ring (2)
^ Tighten each bolt 180 degrees at a time. Alternate between the bolts until both sides of the top
half of J 36652 touch the bottom half of J 36652.
16. Loosen the bolts and remove the halfshaft assembly from J 36652.
17. Remove the convolute retainer tool from the seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7991
Constant Velocity Joint: Service and Repair Wheel Drive Shaft Outer Joint and Seal Replacement
Wheel Drive Shaft Outer Joint and Seal Replacement
^ Tools Required J 8059 Snap Ring Pliers
- J 35910 Seal Clamp Tool
- J 36652 Split Plate Swage Clamp
Disassembly Procedure
Notice: With the removal of the wheel drive shaft for any reason, the transmission sealing surface
(the tripot male/female shank of the joint) should be inspected for corrosion. If corrosion is evident,
the surface should be cleaned with 320 grit cloth or equivalent in a rotational motion only. Do not
clean with an oscillating motion. Transmission fluid may be used to clean off any remaining debris
and the joint wiped dry before installation. Corrosion on the joint sealing surface may damage the
transmission seals and cause a fluid leak.
1. Place protective covers over the vise jaws. Place the halfshaft in the vise.
Important: Use caution when using the hand grinder by the CV joint outer race (1).
2. Use a hand grinder to cut through the swage ring (2). 3. Use side cutters to cut off the small seal
clamp (4).
4. Slide the seal (5) down the halfshaft bar (4) and away from the CV joint outer race (1). 5. Wipe
all grease away from the face of the CV joint. 6. Find the halfshaft bar retaining snap ring (3), which
is located in the inner race (2). 7. Spread the snap ring ears apart using J 8059 (or equivalent). 8.
Pull the CV joint (1) and the CV joint seal (5) from the halfshaft bar (4). 9. Discard the old CV joint
seal (5).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7992
10. Place a brass drift against the CV joint cage (1). 11. Tap gently on the brass drift with a
hammer in order to tilt the cage (1). 12. Remove the first chrome alloy ball (2) when the CV joint
cage (1) tilts. 13. Tilt the CV joint cage (1) in the opposite direction to remove the opposing chrome
alloy ball (2). 14. Repeat this process to remove all six of the balls.
15. Pivot the CV joint cage (4) and the inner race 90 degrees to the center line of the outer race (1).
At the same time, align the cage windows (3) with
the lands of the outer race (2).
16. Lift out the cage (4) and the inner race.
17. Remove the inner race (1) from the cage (2) by rotating the inner race (1) upward. 18. Clean
the following items thoroughly with cleaning solvent. Remove all traces of old grease and any
contaminates.
18.1. The inner and outer race assemblies
18.2. The CV joint cage
18.3. The chrome alloy balls
19. Dry all the parts. 20. Check the CV joint assembly for unusual wear, cracks, or other damage.
21. Replace any damaged parts. 22. Clean the halfshaft bar. Use a wire brush to remove any rust
in the seal mounting area (grooves).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7993
Assembly Procedure
1. Inspect all of the parts for unusual wear, cracks, or other damage. Replace the CV joint
assembly if necessary. 2. Put a light coat of the recommended grease on the inner (6) and the
outer race (8) grooves.
3. Hold the inner race (1) at 90 degrees to the centerline of the cage (2). 4. Align the lands of the
inner race (1) with the windows of the cage (2). 5. Insert the inner race (1) into the cage (2), by
rotating the inner race (1) downward.
6. Insert the cage (4) and inner race into the outer race (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7994
7. Place a brass drift against the CV joint cage (1). 8. Tap gently on the brass drift with a hammer
in order to tilt the cage (1). 9. Install the first chrome alloy ball (2) when the CV joint cage (1) tilts.
10. Tilt the CV joint cage (1) in the opposite direction to install the opposing chrome alloy ball (2).
11. Repeat this process in order to install all six of the balls.
12. Pack the CV joint seal (1) and the CV joint assembly with the grease supplied in the kit. The
amount of grease supplied in this kit has been
pre-measured for this application.
13. Place the new small seal clamp (2) onto the CV joint seal (1). 14. Slide the CV joint seal (1)
onto the halfshaft bar. 15. Position the small end of the CV joint seal (1) into the joint seal groove
(3) on the halfshaft bar.
16. Secure the small seal clamp (1) using J 35910 (or equivalent), a breaker bar, and a torque
wrench.
^ Tighten the small clamp (1) to 136 Nm (100 ft. lbs.).
17. Check the gap dimension on the clamp ear. Continue tightening until the gap dimension is
reached.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7995
18. Pinch the new swage ring (2) slightly by hand to distort it into an oval shape. 19. Slide the
distorted swage ring (2) over the large diameter of the seal (1).
Important: Be sure that the retaining ring side of the CV joint inner race faces the halfshaft bar (3)
before installation. Slide the CV joint (4) onto the halfshaft bar (3). The retaining snap ring inside of
the inner race engages in the halfshaft bar groove with a click when the CV joint (4) is in the proper
position.
20. Pull on the CV joint (4) to verify engagement. 21. Slide the large diameter of the CV joint seal
(1), with the large swage ring (2) in place, over the outside edge of the CV joint outer race (4).
22. Clamp the CV joint seal (2) tightly to the CV joint outer race (1) with the large swage ring (4),
using the following procedure: 23. Mount the base of J 36652 in a vise. 24. Position the CV joint
end (outboard end) of the halfshaft assembly in the bottom half of J 36652.
25. Align the following during this procedure:
^ The CV joint seal (3)
^ The CV joint assembly (1)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint > Component Information > Service and Repair > Wheel Drive Shaft Inner Joint and Seal
Replacement > Page 7996
^ The swage ring (2)
26. Install the top half of J 36652 onto the lower half of the tool, over the CV joint seal (3) and the
CV joint assembly (1). 27. Align the swage ring (2) and the swage ring clamp. 28. Insert the bolts
into J 36652. Hand tighten the bolts until the bolts are snug.
^ Tighten each bolt 180 degrees at a time. Alternate between the bolts until both sides of the top
half of J 36652 touch the bottom half of the tool.
29. Loosen the bolts and remove the halfshaft assembly from J 36652.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service
Constant Velocity Joint Boot: Technical Service Bulletins Drivetrain - Revised Inner Drive Axle Joint
Service
File In Section: 04 - Driveline Axle
Bulletin No.: 03-04-18-003
Date: June, 2003
SERVICE MANUAL UPDATE
Subject: Revised Wheel Drive Shaft Inner Joint and Seal Replacement
Models: 2002-2003 Cadillac Escalade, Escalade EXT 2001-2003 Chevrolet Silverado, Suburban,
Tahoe 2002-2003 Chevrolet Avalanche 2001-2003 GMC Sierra, Suburban, Yukon, Yukon XL 2003
HUMMER H2 with Four Wheel Drive
This bulletin is being issued to revise the Wheel Drive Shaft Inner Joint and Seal Replacement
procedure in the Rear Wheel Drive Shafts sub-section of the Service Manual. Please replace the
current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Wheel Drive Shaft Inner Joint and Seal Replacement
Tools Required
^ J 35910 Seal Clamp Tool
^ J 36652 Drive Axle Clamp Swage Tool
^ J 36652-98 Axle Swage Tool
Disassembly Procedure
Important:
Use caution when using the hand grinder by the tripot housing (1).
1. Use a hand grinder in order to cut through the swage ring (2).
2. Remove the tripot housing (1) from the halfshaft.
3. Wipe the grease off of the housing (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8001
4. Thoroughly degrease the tripot housing (1).
5. Allow the tripot housing (1) to dry prior to assembly.
6. Using side cutters, remove the small boot retaining clamp.
7. Remove the following items from the halfshaft bar:
7.1. The spacer ring (1)
7.2. The tripot spider assembly (2)
7.3. The tripot boot (3)
8. Clean the halfshaft bar (4). Use a wire brush in order to remove any rust in the seal mounting
area (grooves).
9. Inspect the needle rollers, needle bearings, and bearings. Check the tripot housing for unusual
wear, cracks, or other damage. Replace any damaged parts with the appropriate service kit.
Assembly Procedure
1. Place the new small seal clamp (2) onto the small end of the joint seal (1). Compress the joint
seal (1) and small seal clamp (2) onto the halfshaft bar.
2. Position the small end of the joint seal (1) into the joint seal groove (3) on the halfshaft bar.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8002
Notice:
Refer to Fastener Notice in Cautions and Notices.
3. Secure the small seal clamp (1) with J 35910 (or equivalent), a breaker bar, and a torque wrench
Tighten
Tighten the small seal clamp (1) to 136 N.m (100 lb ft).
4. Check the gap dimension on the clamp ear. Continue tightening until the gap dimension is
reached.
Important:
Assemble the tripot joint with the convolute retainer in the correct position, as illustrated.
5. Install the convolute retainer tool over the inboard joint seal, being sure to capture the following
convolutions:
^ 2-5 for the 1500 model (except 1500HD)
^ 2-4 for the 1500HD, 2500, 3500, and HUMMER H2 models.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8003
6. Install the tripot spider assembly (3) onto the halfshaft bar (2).
7. Install the spacer ring (1) in the groove at the end of the halfshaft bar (2).
8. Pack the tripot seal (4) and the tripot housing (1) with the grease supplied in the kit. The amount
of grease supplied in this kit has been pre-measured for this application.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8004
9. Reassemble the tripot housing and the tripot seal using the following procedure:
9.1. Pinch the swage ring (2) slightly by hand in order to distort it into an oval shape.
9.2. Slide the distorted swage ring (2) over the large diameter of the seal.
9.3. Place the tripot housing over the spider assembly.
9.4. Install the seal onto the tripot housing.
9.5. Align the tripot seal (1), with the swage ring (2) in place, over the flat area on the tripot housing
(3).
10. For the 1500 models (except 1500HD), assemble the bolts and the support plate to the base of
the J-36652-01 and secure the base in a vise.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8005
11. For the 1500HD, 2500, 3500, and HUMMER H2 models, assemble the bolts and the support
plate to the base of the J 36652-98 and secure the base in a vise.
12. Inspect the inboard stroke position.
^ Use measurement A for the 1500 models (except 1500HD).
^ Use measurement B for the 1500HD, 2500, 3500, and HUMMER H2 models.
13. Position the inboard end (tripot end) of the halfshaft assembly into the base of the J-36652-01
for the 1500 models (except 1500HD) or J 36652-98 for the 1500HD, 2500, 3500 and HUMMER
H2 models.
14. Install the top half of the J-36652-01 for the 1500 models (except 1500HD) or J 36652-98 for
the 1500HD, 2500, 3500 and HUMMER H2 models.
15. Align the swage ring (2) and the swage ring clamp.
16. Insert the bolts.
Tighten
Hand tighten the bolts until the bolts are snug.
Important:
Align the following during this procedure:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Drivetrain - Revised Inner Drive Axle
Joint Service > Page 8006
^ The tripot boot (3)
^ The tripot housing (1)
^ The swage ring (2)
Tighten
Tighten each bolt 180 degrees at a time. Alternate between the bolts until both sides of the top half
of the tool touch the bottom half.
17. Loosen the bolts and remove the halfshaft assembly from the tool.
18. Remove the convolute retainer tool from the boot.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Page 8007
Constant Velocity Joint Boot: Service and Repair
Wheel Drive Shafts Boot Cover Replacement
^ Tools Required J 41187 Band-it Type Tool
Disassembly Procedure
Important: Be careful when removing the clamps from the halfshaft seal cover, If reusing the
halfshaft seal cover.
1. Use side cutters to cut the halfshaft seal cover clamps (2) and the nylon strap (1).
2. Slide the halfshaft seal cover (1) off of the halfshaft, over the CV joint end. 3. Check the halfshaft
seal cover (1) for rips, tears, worn spots or other damage. Reuse the halfshaft seal cover (1) if
there is no damage visible.
Assembly Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Page 8008
1. Insert new clamps (3) into the original halfshaft seal cover (1) (if you are reusing the original
halfshaft seal cover). 2. Slide the halfshaft seal cover (1) onto the halfshaft assembly (2), starting at
the outboard (CV joint) end.
3. Align the inboard clamp (2) on the inboard joint (1). Align the seal cover seam so the seam is
straight.
Important: Tighten the seal cover clamp (1) as tight as possible without deforming the retaining clip.
Clamps that are not tight enough allow the cover to slide upon the joint. This causes shortened
service life.
4. Use J 41187 in order to tighten the inboard seal cover clamp (1).
5. Rotate J41187 toward the clip in order to bend the band onto the clip. 6. Pull on the tool's cutting
handle in order to cut off the excess band.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Page 8009
7. Pound the band flat between the latch tabs. Peen the latch tabs over in order to lock the band
into position.
8. Twist the halfshaft seal cover (1):
^ K15 = 180 degrees
^ K25 = 90 degrees
Important: Be sure that the inboard tab of the halfshaft seal cover (1) is 180 degrees opposite the
outboard tab of the halfshaft seal cover (1) before proceeding.
9. Position the outboard end of the halfshaft seal cover (1) over the CV joint (2) flat.
Important: Tighten the seal cover clamp (1) as tight as possible without deforming the retaining clip.
Clamps that are not tight enough allow the cover to slide upon the joint. This causes shortened
service life.
10. Use J 41187 in order to tighten the outboard cover clamp (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Axle Shaft Assembly >
Constant Velocity Joint Boot > Component Information > Technical Service Bulletins > Page 8010
11. Rotate J 41187 toward the clip in order to bend the band onto the clip. 12. Pull the tool's cutting
handle in order to cut off the excess band.
13. Pound the band flat between the latch tabs. Peen the latch tabs over in order to lock the band
into position.
14. Gather the halfshaft seal cover material at the center. Wrap the halfshaft seal cover (1) tightly
with the nylon strap (2) provided in the kit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Seals and Gaskets, Drive
Axles > System Information > Technical Service Bulletins > Customer Interest for Seals and Gaskets: > 08-07-30-009B >
May > 08 > A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
Seals and Gaskets: Customer Interest A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Seals and Gaskets, Drive
Axles > System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: >
08-07-30-009B > May > 08 > A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
Seals and Gaskets: All Technical Service Bulletins A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Seals and Gaskets, Drive
Axles > System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > Page
8024
Seals and Gaskets: By Symptom
Technical Service Bulletin # 08-07-30-009B Date: 080501
A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Technical Service Bulletin # 08-07-30-009B Date: 080501
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Seals and Gaskets, Drive
Axles > System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > Page
8025
A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Technical Service Bulletin # 08-07-30-009B Date: 080501
A/T - 4T80E, Slips in Gear/L/H Axle Seal Leaks
TECHNICAL
Bulletin No.: 08-07-30-009B
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Seals and Gaskets, Drive
Axles > System Information > Technical Service Bulletins > All Technical Service Bulletins for Seals and Gaskets: > Page
8026
Date: May 01, 2008
Subject: HYDRA-MATIC(R) Front Wheel Drive 4T80-E (MH1) Left Front Axle Seal Leak,
Transmission Slips in Gear (Replace Third Clutch Housing with Revised Service Part)
Models: 2001-2008 GM Passenger Cars
with HYDRA-MATIC(R) Front Wheel Drive 4T80-E Automatic Transmission (RPO - MH1)
Supercede:
This bulletin is being updated to revise the Warranty Information. Please discard Corporate Bulletin
Number 08-07-30-009A (Section 07 - Transmission/Transaxle).
Condition
Some customers may comment on a transmission oil leak and/or that the transmission slips in
gear.
Cause
An oil leak may be caused by bushing wear in the third clutch housing, causing excessive fluid
build-up at axe sea.
Correction
Important:
DO NOT replace the transmission for above concerns.
Replace the third clutch housing with service P/N 8682114, which has revised bushing material to
extend life and reduce left front axle seal leaks. Refer to Automatic/Transaxle - 4T80-E
Transmission Off-Vehicle Repair Instructions for the replacement of the third clutch housing in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Bearing >
Component Information > Technical Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure
Wheel Bearing: Technical Service Bulletins Drive Train - Revised Wheel Bearing Adjustment
Procedure
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-20-002
Date: May, 2002
SERVICE MANUAL UPDATE
Subject: Revised Wheel Bearing Adjustment Procedure
Models:
2001-2002 Chevrolet and GMC C/K and G-Van Models with 10.5 and 11.5 Inch Axles
This bulletin is being issued to revise the Wheel Bearing Adjustment procedure in the Rear Drive
Axle sub-section of the Service Manual. Please replace the current information in the Service
Manual with the following information.
The following information has been updated within Service Information (SI). If you are using a
paper version of this Service Manual, please make a reference to this bulletin on the affected page.
Wheel Bearing Adjustment
Preliminary Inspection
Important:
Ensure the brakes are fully released and do not drag.
Pull or push the tire at the top back and forth in order to test the wheel bearing play.
^ Use a pry bar under the tire as an alternative.
^ If the wheel bearing adjustment is correct, the movement will be barely noticeable.
^ If the movement is excessive, adjust the bearings.
Adjustment Procedure Tools Required J 2222-C Wheel Bearing Nut Wrench
1. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the axle shaft. Refer to Rear Axle Shaft and/or Gasket Replacement.
3. Remove the hub adjuster nut retaining ring.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Bearing >
Component Information > Technical Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure > Page
8031
4. Remove the adjuster nut lock key.
Notice:
Refer to Fastener Notice in Cautions and Notices.
5. Tighten the wheel bearing adjusting nut using the J 2222-C.
Rotate the hub in the opposite direction to the way the adjuster nut is turning.
Ensure the inner bearing and the seal seats against the spindle shoulder.
Tighten
Tighten the adjusting nut to 70 N.m (52 lb ft).
6. Turn the adjusting nut counterclockwise until the nut is loose using the J 2222-C.
7. Turn the adjusting nut clockwise until the nut contacts the bearing cone. Torque on the nut must
be zero to finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Bearing >
Component Information > Technical Service Bulletins > Drive Train - Revised Wheel Bearing Adjustment Procedure > Page
8032
8. Insert the adjusting nut lock key into the keyway using one of the following procedures:
^ If the adjusting nut slot is in alignment with the keyway in the axle spindle, insert the adjusting nut
lock key into the keyway in the axle spindle.
Important:
Do not turn the adjusting nut more than one slot counterclockwise in order to align the adjusting nut
slot with the keyway in the axle spindle.
^ If the adjusting nut slot is not aligned with the keyway in the axle spindle, turn the adjusting nut
counterclockwise until the adjusting nut slot is in alignment with the keyway in the axle spindle and
insert the adjusting nut lock key.
9. Install the retaining ring.
10. Install the axle shaft. Refer to Rear Axle Shaft and/or Gasket Replacement.
11. Inspect the lubricant level and add, if necessary. Refer to Lubricant Level Check.
12. Lower the vehicle.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Bearing >
Component Information > Technical Service Bulletins > Page 8033
Wheel Bearing: Service and Repair
"For information regarding this component please refer to wheel hub service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Hub > Axle Nut >
Component Information > Specifications
Axle Nut: Specifications
Front Axle Shaft Nut ............................................................................................................................
................................................ 210 Nm (155 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive Axles, Bearings and Joints > Wheel Seal > Component
Information > Service and Repair
Wheel Seal: Service and Repair
"For information regarding this component please refer to wheel hub service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Center Support
> Component Information > Specifications
Center Support: Specifications
Center Bearing Mounting Bolt .............................................................................................................
.................................................... 40 Nm (30 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Specifications
Drive/Propeller Shaft: Specifications
Propeller Shaft
Fastener Tightening Specifications
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Diagrams > Front Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Diagrams > Front Propeller Shaft > Page 8050
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Diagrams > Page 8051
Drive/Propeller Shaft: Description and Operation
Propeller Shaft Description and Operation
The propeller shaft is a tube with universal joints at both ends that do not require periodic
maintenance. The universal joints transmit power from the transfer case, or from the transmission
output shaft, to the differential.
Front Propeller Shaft Description
The front propeller shaft transmits rotating force from the transfer case to the front differential when
the transfer case is engaged. The front propeller shaft connects to the transfer case using a splined
slip joint.
One-Piece Propeller Shaft Description
A one-piece propeller shaft uses a splined slip joint in order to connect the driveline to the
transmission, or to the transfer case.
Propeller Shaft Phasing Description
The propeller shaft is designed and built with the yoke lugs, or the ears, in-line with each other.
This produces the smoothest running shaft possible. A propeller shaft that is designed with built-in
yoke lugs in-line is known as in-phase. An out-of-phase propeller shaft often causes vibration. The
propeller shaft generates vibration from speeding up and from slowing down each time that the
universal joint spins around. The vibration is similar to a person snapping a rope and watching the
wave reaction flow to the end. An in-phase propeller shaft is similar to 2 persons snapping a rope
at the same time and watching the waves meet and cancel each other. Canceling the vibration
produces a smooth flow of power in the drive line. All splined shaft slip yokes are keyed in order to
ensure proper phasing.
Universal Joint Description
The universal joint is connected to the propeller shaft. The universal joint consists of 4 caps with
needle bearings and with grease seals. The caps and the seals are mounted on the trunnions of a
cross or of a spider. The bearings and the caps are greased at the factory. No periodic
maintenance is required. Two universal joints are used in a one-piece propeller shaft. Three
universal joints are used in a two-piece propeller shaft. The bearings and the caps are pressed into
the yokes. The bearings and the caps are held in place with snap rings, except for 2 bearings On
some models. These bearings on some models are attached to the pinion flange of the differential.
Universal joints handle the effects of various loads and of rear axle windup conditions during
acceleration and braking. The universal joint operation is efficient and safe within the designed
angle variations. When the design angle is exceeded, the operational life of the joint decreases.
Center Bearing Description
Center bearings support the driveline when using 2 or more propeller shafts. The center bearing is
a ball bearing in a rubber cushion that attaches to a frame crossmember. The manufacturer
lubricates the bearing and seals the bearing. The cushion allows vertical motion at the driveline and
helps isolate the vehicle from vibration.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview
Drive/Propeller Shaft: Initial Inspection and Diagnostic Overview
Diagnostic Starting Point - Propeller Shaft
Begin the system diagnosis by reviewing the system Description and Operation. Reviewing the
Description and Operation information will help you determine the correct symptom diagnostic
procedure when a malfunction exists. Reviewing the Description and Operation information will
also help you determine if the condition described by the customer is normal operation. Refer to
Symptoms - Propeller Shaft in order to identify the correct procedure for diagnosing the system and
where the procedure is located. See: Symptom Related Diagnostic Procedures/- Symptoms Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 8054
Drive/Propeller Shaft: Symptom Related Diagnostic Procedures
- Symptoms - Propeller Shaft
Symptoms - Propeller Shaft
Before beginning diagnosis, review the system description and operation in order to familiarize
yourself with the system function.
Classifying the Symptom
Propeller Shaft symptoms can usually be classified into the following categories: ^
Leaks
^ Noises
^ Vibrations
Leak and noise related symptoms are diagnosed within the Propeller Shaft section. For vibration
related symptoms, refer to Diagnostic Starting Point - Vibration Diagnosis and Correction.
Visual/Physical Inspection
^ Inspect the system for aftermarket devices, which could affect the operation of the Propeller
Shaft.
^ Inspect the easily accessible or visible system components for obvious damage or conditions,
which could cause the symptom.
Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:
^
Leak at Front Slip Yoke See: Leak at Front Slip Yoke
^ Universal Joint Noise See: Universal Joint Noise
^ Ping, Snap, or Click Noise See: Ping, Snap, or Click Noise
^ Knock or Clunk Noise See: Knock or Clunk Noise
^ Scraping Noise See: Scraping Noise
^ Squeak Noise See: Squeak Noise
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Testing and Inspection > Initial Inspection and Diagnostic Overview > Page 8055
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front
Drive/Propeller Shaft: Service and Repair Propeller Shaft Replacement- Front
Propeller Shaft Replacement- Front
^ Tools Required J 43218 Clamp Pliers Narrow Jaw
Removal Procedure
Important: Before disassembly, observe and accurately mark all of the driveline components
relative to the propeller shaft and to the axles. These items include the following components: ^
The propeller shafts
^ The wheel drive shafts
^ The pinion flanges
^ The output shafts
Assemble all of the components in the exact relationship to each other prior to removal. Observe all
published specifications and torque values, and any measurements obtained prior to disassembly.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield, if equipped. 3.
Mark the relationship of the propeller shaft and of the front axle pinion yoke. 4. Remove the clamp
(4) at the transfer case (3) by prying up the exposed end of the clamp (4) with a flat-bladed tool.
5. Remove the bolts (6) and the yoke retainers (7) from the front axle pinion yoke (1).
Notice: When removing the propeller shaft, do not attempt to remove the shaft by pounding on the
yoke ears or using a tool between the yoke and the universal joint. If the propeller shaft is removed
by using such means, the injection joints may fracture and lead to premature failure of the joint.
6. Disconnect the propeller shaft (2) from the front axle pinion yoke (1).
Wrap the bearing caps with tape in order to prevent the loss of bearing rollers.
Important: Do not drop the bearing cap assemblies of the yoke end.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front > Page 8058
7. Remove the propeller shaft (5) from the transfer case output shaft by sliding the propeller shaft
forward.
Installation Procedure
1. Inspect the splines of the transfer case output shaft for a sufficient coating of lubricant. If the
output shaft does not have a sufficient coating of
lubricant, lubricate the shaft with lubricant GM P/N 12345879 (Canadian P/N 10953511) or with an
equivalent lubricant meeting GM specification 9985830.
2. Install the new clamp into the groove of the propeller shaft boot. 3. Install the propeller shaft
splines into the transfer case output shaft.
4. Install the propeller shaft (5) to the front axle pinion yoke (1).
Align the reference marks that were made during removal.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the yoke retainers (7) and the bolts (6).
^ Tighten the yoke retainer bolts to 25 Nm (19 ft. lbs.).
6. Install the boot onto the transfer case output shaft until the boot is attached into the groove on
the output shaft.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front > Page 8059
7. Using the J 43218 crimp the clamp until the dimensions that are shown are obtained. 8. Install
the transfer case shield, if equipped. 9. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front > Page 8060
Drive/Propeller Shaft: Service and Repair Propeller Shaft Replacement- Rear
Propeller Shaft Replacement- Rear
Removal Procedure
Important: Observe and accurately reference mark all driveline components relative to the propeller
shaft and axles before disassembly. These components include the propeller shafts, the drive
axles, the pinion flanges, the output shafts, etc. All components must be reassembled in the exact
relationship to each other as they were when removed. In addition, published specifications and
torque values, as well as any measurements made prior to disassembly must be followed.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Reference mark the propeller shaft to the rear axle
pinion yoke. 3. Reference mark the propeller shaft to the transmission or transfer case. 4. Remove
the bolts (1) and the yoke retainers (2) from the rear axle pinion yoke (3).
Notice: When removing the propeller shaft, do not attempt to remove the shaft by pounding on the
yoke ears or using a tool between the yoke and the universal joint. If the propeller shaft is removed
by using such means, the injection joints may fracture and lead to premature failure of the joint.
5. Slide the propeller shaft forward in order to disconnect the propeller shaft from the rear axle
pinion yoke.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front > Page 8061
6. Slide the propeller shaft rearward in order to disconnect the propeller shaft from the transmission
or transfer case. 7. Remove the propeller shaft from the vehicle.
Installation Procedure
1. Inspect the splines of the slip yoke for a sufficient coating of lubricant. If the splines of the slip
yoke does not have a sufficient coating of lubricant,
lubricate the shaft with lubricant GM P/N 12345879 (Canadian P/N 10953511) or with an equivalent
lubricant meeting GM specification 9985830 (RWD w/ Automatic Transmission).
2. Install the propeller shaft into the transmission or transfer case.
Align the reference marks made during removal.
3. Install the propeller shaft (3) to the rear axle pinion yoke (4).
Align the reference marks made during removal.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the yoke retainers (2) and bolts (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Propeller Shaft Replacement- Front > Page 8062
^ Tighten the yoke retainer bolts to 25 Nm (19 ft. lbs.).
5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Drive/Propeller
Shaft > Component Information > Service and Repair > Page 8063
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises
Slip Yoke: Customer Interest Driveline - Bump/Clunk/Squawking Noises
Bulletin No.: 01-04-17-004B
Date: January 05, 2005
TECHNICAL
Subject: Clunk, Bump or Squawk when Vehicle Comes to Complete Stop or Accelerating from
Complete Stop (Replace Rear Drive Shaft Nickel-Plated Slip Yoke)
Models
Supercede:
This bulletin is being revised to add Cadillac Escalade (Old Style) to the Models section. Please
discard Corporate Bulletin Number 01-04-17-004A (Section 04 - Driveline/Axle).
Condition
Some customers may comment on a clunk, bump or squawk noise when the vehicle comes to a
stop or when accelerating from a complete stop.
Cause
A slip/stick condition between the transfer case output shaft and the driveshaft slip yoke may cause
this condition.
Diagnostic Tips
There are several resources in the electronic Service Information System which can provide the
technician with information on diagnosis and repair of clunk conditions, and fix the customer's
vehicle right the first time without unnecessary parts replacement. Some of the documents
available in SI include:
^ Symptoms - Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8072
^ Knock or Clunk Noise
^ Rear Drive Axle Noises (SI Document ID #700580)
^ Launch Shudder/Vibration on Acceleration (Replace Propeller Shaft and Install a New Pinion
Flange/Seal), Bulletin # 02-04-17-001
^ Information on 2-3 Upshift or 3-2 Downshift Clunk Noise, Bulletin # 01-07-30-042
^ Driveline Clunk When Stopping (Reprogram Powertrain Control Module (PCM), Bulletin #
03-07-30-028
Correction
Replace the rear drive shaft slip yoke with a new nickel-plated slip yoke. See the parts table below.
Follow the service procedure below.
1. Raise the vehicle on a hoist.
2. Reference mark the propeller shaft to the pinion flange connection.
Important:
Do not pound on the propeller shaft yoke ears. Never pry or place any tool between a yoke and a
universal joint.
3. Remove the bolts and the yoke retainers from the pinion flange.
4. Slide the propeller shaft forward and out of the rear pinion flange.
5. Lower the rear of the propeller shaft and pull the driveshaft out of the transfer case.
Note:
Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube causing an
imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
6. Support the propeller shaft in a line horizontal with the table of a press.
Important:
Remove the front slip yoke and the universal joint together. The new nickel-plated slip yoke comes
with a new universal joint.
7. Disassemble the snap rings by pinching the ends together with a pair of pliers.
8. If the ring does not readily snap out of the groove in the yoke, tap the end of the cup lightly in
order to relieve the pressure from the ring.
9. Place the universal joint so that the lower ear of the yoke is supported on a 30 mm (1-1/8 in) hex
head socket or a 27 mm (1-1/16 in) socket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8073
10. Place the J 9522-3 on the open horizontal bearing cups. Press the lower bearing cup out of the
yoke ear.
11. If you do not completely remove the bearing cup, lift the cross and insert the J 9522-5 between
the seal and the bearing cup you are removing. Continue pressing the bearing cup out of the yoke.
12. Rotate the propeller shaft. Press the opposite bearing cup out of the drive shaft yoke.
13. Remove the old slip yoke and universal joint.
14. Inspect the retaining ring grooves for dirt, corrosion, or pieces of the old ring.
15. Inspect the bearing cup bores for burrs or imperfections.
16. Clean the retaining ring grooves. Corrosion, dirt, rust, or pieces of the old retaining ring may
prevent the bearing cups from pressing into place or prevent the bearing retainers from properly
seating.
17. Install the new nickel-plated slip yoke and universal joint. See parts table below for parts
information.
18. Remove the bearing cups from the universal joint.
19. Assemble one bearing cup part way into one side of the yoke. Turn the yoke ear toward the
bottom.
20. Assemble the cross into the yoke so that the trunnion seats freely into the bearing cup.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8074
21. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until the
bearing cup is flush with the yoke ear.
22. Install the opposite bearing cup part way into the yoke ear.
23. Ensure that the trunnions start straight and true into both bearing cups.
24. Press the opposite bearing cup into the yoke ear while working the cross all the time in order to
inspect for free unbinding movement of the trunnions in the bearing cups.
Important:
If there seems to be a hang up or binding, stop pressing. Inspect the needle bearings for
misalignment in the bearing cup.
25. Press the bearing cup into the yoke until the bearing cup retainer groove is visible over the top
of the bearing cup.
26. Assemble the bearing retainer in the retainer groove.
27. Continue pressing until both retainers can be snapped into place.
28. If the retainer is difficult to seat, the yoke can be sprung slightly with a firm blow from a
soft-faced dead blow hammer.
29. It may be necessary to lubricate the snap ring with a slight amount of chassis grease so that
the snap ring seats in the bearing cup groove.
30. Install the slip yoke onto the output shaft in the transfer case.
31. Align the reference marks on the pinion flange and the propeller shaft.
32. Install the yoke retainers and bolts.
Tighten
Tighten the yoke retainer bolts to 25 N.m (19 lb ft).
33. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8075
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8076
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8077
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8078
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8079
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8080
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Customer Interest for Slip Yoke: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8081
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises
Slip Yoke: All Technical Service Bulletins Driveline - Bump/Clunk/Squawking Noises
Bulletin No.: 01-04-17-004B
Date: January 05, 2005
TECHNICAL
Subject: Clunk, Bump or Squawk when Vehicle Comes to Complete Stop or Accelerating from
Complete Stop (Replace Rear Drive Shaft Nickel-Plated Slip Yoke)
Models
Supercede:
This bulletin is being revised to add Cadillac Escalade (Old Style) to the Models section. Please
discard Corporate Bulletin Number 01-04-17-004A (Section 04 - Driveline/Axle).
Condition
Some customers may comment on a clunk, bump or squawk noise when the vehicle comes to a
stop or when accelerating from a complete stop.
Cause
A slip/stick condition between the transfer case output shaft and the driveshaft slip yoke may cause
this condition.
Diagnostic Tips
There are several resources in the electronic Service Information System which can provide the
technician with information on diagnosis and repair of clunk conditions, and fix the customer's
vehicle right the first time without unnecessary parts replacement. Some of the documents
available in SI include:
^ Symptoms - Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8087
^ Knock or Clunk Noise
^ Rear Drive Axle Noises (SI Document ID #700580)
^ Launch Shudder/Vibration on Acceleration (Replace Propeller Shaft and Install a New Pinion
Flange/Seal), Bulletin # 02-04-17-001
^ Information on 2-3 Upshift or 3-2 Downshift Clunk Noise, Bulletin # 01-07-30-042
^ Driveline Clunk When Stopping (Reprogram Powertrain Control Module (PCM), Bulletin #
03-07-30-028
Correction
Replace the rear drive shaft slip yoke with a new nickel-plated slip yoke. See the parts table below.
Follow the service procedure below.
1. Raise the vehicle on a hoist.
2. Reference mark the propeller shaft to the pinion flange connection.
Important:
Do not pound on the propeller shaft yoke ears. Never pry or place any tool between a yoke and a
universal joint.
3. Remove the bolts and the yoke retainers from the pinion flange.
4. Slide the propeller shaft forward and out of the rear pinion flange.
5. Lower the rear of the propeller shaft and pull the driveshaft out of the transfer case.
Note:
Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube causing an
imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
6. Support the propeller shaft in a line horizontal with the table of a press.
Important:
Remove the front slip yoke and the universal joint together. The new nickel-plated slip yoke comes
with a new universal joint.
7. Disassemble the snap rings by pinching the ends together with a pair of pliers.
8. If the ring does not readily snap out of the groove in the yoke, tap the end of the cup lightly in
order to relieve the pressure from the ring.
9. Place the universal joint so that the lower ear of the yoke is supported on a 30 mm (1-1/8 in) hex
head socket or a 27 mm (1-1/16 in) socket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8088
10. Place the J 9522-3 on the open horizontal bearing cups. Press the lower bearing cup out of the
yoke ear.
11. If you do not completely remove the bearing cup, lift the cross and insert the J 9522-5 between
the seal and the bearing cup you are removing. Continue pressing the bearing cup out of the yoke.
12. Rotate the propeller shaft. Press the opposite bearing cup out of the drive shaft yoke.
13. Remove the old slip yoke and universal joint.
14. Inspect the retaining ring grooves for dirt, corrosion, or pieces of the old ring.
15. Inspect the bearing cup bores for burrs or imperfections.
16. Clean the retaining ring grooves. Corrosion, dirt, rust, or pieces of the old retaining ring may
prevent the bearing cups from pressing into place or prevent the bearing retainers from properly
seating.
17. Install the new nickel-plated slip yoke and universal joint. See parts table below for parts
information.
18. Remove the bearing cups from the universal joint.
19. Assemble one bearing cup part way into one side of the yoke. Turn the yoke ear toward the
bottom.
20. Assemble the cross into the yoke so that the trunnion seats freely into the bearing cup.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8089
21. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until the
bearing cup is flush with the yoke ear.
22. Install the opposite bearing cup part way into the yoke ear.
23. Ensure that the trunnions start straight and true into both bearing cups.
24. Press the opposite bearing cup into the yoke ear while working the cross all the time in order to
inspect for free unbinding movement of the trunnions in the bearing cups.
Important:
If there seems to be a hang up or binding, stop pressing. Inspect the needle bearings for
misalignment in the bearing cup.
25. Press the bearing cup into the yoke until the bearing cup retainer groove is visible over the top
of the bearing cup.
26. Assemble the bearing retainer in the retainer groove.
27. Continue pressing until both retainers can be snapped into place.
28. If the retainer is difficult to seat, the yoke can be sprung slightly with a firm blow from a
soft-faced dead blow hammer.
29. It may be necessary to lubricate the snap ring with a slight amount of chassis grease so that
the snap ring seats in the bearing cup groove.
30. Install the slip yoke onto the output shaft in the transfer case.
31. Align the reference marks on the pinion flange and the propeller shaft.
32. Install the yoke retainers and bolts.
Tighten
Tighten the yoke retainer bolts to 25 N.m (19 lb ft).
33. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8090
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8091
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8092
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8093
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8094
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8095
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Slip Yoke: > 01-04-17-004B > Jan
> 05 > Driveline - Bump/Clunk/Squawking Noises > Page 8096
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Slip Yoke >
Component Information > Technical Service Bulletins > Page 8097
Slip Yoke: Specifications
Yoke Retainer Bolts .............................................................................................................................
..................................................... 25 Nm (19 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring
Universal Joint: Service and Repair Universal Joint Replacement - Nylon Injected Ring
Universal Joint Replacement - Nylon Injected Ring
^ Tools Required J 9522-3 U Joint Bearing Separator
- J 9522-5 U Joint Bearing Spacer Remover
Disassembly Procedure
Notice: Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube
causing an imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
1. Support the propeller shaft in a line horizontal with the table of a press. 2. Mark the propeller
shaft as to which end is the transmission end and which end goes to the rear axle. 3. Place the
universal joint so that the lower ear of the yoke is supported on a 30 mm (1 1/8 inch) socket.
4. In order to shear the plastic retaining ring on the bearing cup, place J 9522-3 on the open
horizontal bearing cups. Press the lower bearing cup out
of the yoke ear.
5. If you do not completely remove the bearing cup, lift the cross and insert J 9522-5 between the
seal and the bearing cup you are removing.
Continue to press the bearing cup out of the yoke.
6. Rotate the propeller shaft. Press the opposite bearing cup out of the yoke. 7. Mark the
orientation of the slip yoke to the tube for proper reassembly. 8. Remove the cross from the yoke.
9. Remove the remaining universal joint parts from the yoke. If you are replacing the front universal
joint, remove the bearing cups in the slip yoke in
the same manner.
10. Inspect the retaining ring grooves for plastic. 11. Inspect the bearing cup bores in the yoke ears
for burrs or imperfections. 12. Clean the remains of the sheared plastic bearing retainers from the
grooves in the yoke. 13. The sheared plastic may prevent the bearing cups from pressing into
place and thus prevent the bearing retainers from properly seating.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring >
Page 8102
Assembly Procedure
1. Remove the bearing cups from the universal joint. 2. Assemble 1 bearing cup part way into 1
side of the yoke. 3. Turn the yoke ear toward the bottom. 4. Assemble the cross into the yoke so
the trunnion seats freely into the bearing cup. 5. With the trunnion seated in the bearing cup, press
the bearing cup into the yoke until the bearing cup is flush with the yoke ear.
6. Assemble the opposite bearing cup part way into the yoke ear. 7. Ensure that the trunnions start
straight and true into both bearing cups. 8. Press the opposite bearing cup into the yoke ear while
working the cross all the time in order to inspect for a free unbinding movement of the
trunnions in the bearing cups.
Important: If there seems to be a hangup or binding, stop pressing, and inspect the needle
bearings for misalignment in the bearing cup.
9. Press the bearing cup into the yoke until the bearing retainer groove clears the inside of the
yoke.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring >
Page 8103
10. Assemble the bearing retainer in the retainer groove. 11. Continue pressing until you can snap
both retainers into place.
12. If seating the retainer is difficult, spring the yoke slightly with a firm blow from a dead blow
hammer. 13. It may be necessary to lubricate the snap ring with a slight amount of chassis grease
so the snap ring seats in the bearing cup groove.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring >
Page 8104
Universal Joint: Service and Repair Universal Joint Replacement- External Snap Ring
Universal Joint Replacement- External Snap Ring
^ Tools Required J 9522-3 U-Joint Bearing Separator
- J 9522-5 U-Joint Bearing Spacer Remover
Disassembly Procedure
Notice: Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube
causing an imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
1. Support the propeller shaft in a line horizontal with the table of a press. 2. Mark the propeller
shaft in order to show which end connects to the transmission and which end goes to the rear axle.
3. Disassemble the snap rings by pinching the ends together with a pair of pliers. 4. If the ring does
not readily snap out of the groove in the yoke, tap the end of the cup lightly in order to relieve the
pressure from the ring. 5. Place the universal joint so that the lower ear of the yoke is supported on
a 30 mm (1-1/8 inch) hex head socket or a 27 mm (1-1/16 inch) socket.
6. Place J 9522-3 on the open horizontal bearing cups. Press the lower bearing cup out of the yoke
ear. 7. If you do not completely remove the bearing cup, lift the cross and insert J 9522-5 between
the seal and the bearing cup you are removing.
Continue pressing the bearing cup out of the yoke.
8. Rotate the propeller shaft. Press the opposite bearing cup out of the yoke. 9. Mark the
orientation of the slip yoke to the tube for proper reassembly.
10. Remove the cross from the yoke. 11. Remove the remaining universal joint parts from the yoke.
12. If you are replacing the front universal joint, remove the bearing cups in the slip yoke in the
same manner. 13. Inspect the retaining ring grooves for dirt, corrosion, or pieces of the old ring. 14.
Inspect the bearing cup bores for burrs or imperfections. 15. Clean the retaining ring grooves.
Corrosion, dirt, rust, or pieces of the old retaining ring may prevent the bearing cups from pressing
into place or
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring >
Page 8105
prevent the bearing retainers from properly seating.
Assembly Procedure
1. Remove the bearing cups from the universal joint. 2. Assemble 1 bearing cup part way into 1
side of the yoke. Turn the yoke ear toward the bottom. 3. Assemble the cross into the yoke so that
the trunnion seats freely into the bearing cup.
4. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until the bearing
cup is flush with the yoke ear. 5. Install the opposite bearing cup part way into the yoke ear. 6.
Ensure that the trunnions start straight and true into both bearing cups. 7. Press the opposite
bearing cup into the yoke ear while working the cross all the time in order to inspect for free
unbinding movement of the
trunnions in the bearing cups.
Important: If there seems to be a hang up or binding, stop pressing. Inspect the needle bearings for
misalignment in the bearing cup.
8. Press the bearing cup into the yoke until the bearing cup retainer groove is visible over the top of
the bearing cup.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Drive/Propeller Shafts, Bearings and Joints > Universal Joint,
Drive/Propeller Shaft > Component Information > Service and Repair > Universal Joint Replacement - Nylon Injected Ring >
Page 8106
9. Assemble the bearing retainer in the retainer groove.
10. Continue pressing until both retainers can be snapped into place.
11. If the retainer is difficult to seat, the yoke can be sprung slightly with a firm blow from a dead
blow hammer. 12. It may be necessary to lubricate the snap ring with a slight amount of chassis
grease so that the snap ring seats in the bearing cup groove.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Flex Plate > Component Information > Specifications >
Flywheel to Crankshaft Bolts
Flex Plate: Specifications Flywheel to Crankshaft Bolts
Engine Flywheel Bolt
First Pass .............................................................................................................................................
.................................................. 20 Nm (15 ft. lbs.) Second Pass .......................................................
................................................................................................................................... 50 Nm (37 ft.
lbs.) Final Pass ....................................................................................................................................
........................................................ 100 Nm (74 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Flex Plate > Component Information > Specifications >
Flywheel to Crankshaft Bolts > Page 8111
Flex Plate: Specifications Flywheel to Torque Converter Bolts
4L60-E
Flywheel to Torque Converter Bolt
...................................................................................................................................................... 63
Nm (46 ft. lbs.)
4L80-E
Flywheel to Converter ..........................................................................................................................
................................................ 43 Nm (32 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Flex Plate > Component Information > Specifications > Page
8112
Flex Plate: Service and Repair
Engine Flywheel Replacement
Removal Procedure
1. Remove the automatic transmission.
Important: Note the position and direction of the engine flywheel before removal.
2. Remove the engine flywheel bolts. 3. Remove the automatic transmission engine flywheel.
4. Install two M11x1.5 mm bolts (1) to the threaded holes of the spacer, if applicable. 5. Rotate the
bolts clockwise to remove the spacer.
6. Remove the spacer from the rear of the crankshaft, if applicable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Flex Plate > Component Information > Specifications > Page
8113
Installation Procedure
Important: The flywheel does not use a locating pin for alignment and will not initially seat against the
crankshaft flange or spacer (if applicable), but will be pulled onto the crankshaft by the engine
flywheel bolts. This procedure requires a three stage tightening process.
- Certain applications (6.0L) require a spacer and longer bolts for proper flywheel position.
1. Install the spacer (if applicable) onto the rear of the crankshaft.
2. Install the automatic transmission engine flywheel to the crankshaft.
Important: Longer flywheel bolts must be used on applications using a flywheel spacer.
3. Apply threadlock GM P/N 12345382, Canada P/N 10953489, or equivalent to the threads of the
flywheel bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Flex Plate > Component Information > Specifications > Page
8114
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the engine flywheel bolts.
4.1. Tighten the engine flywheel bolts a first pass in sequence to 20 Nm (15 ft. lbs.).
4.2. Tighten the engine flywheel bolts a second pass in sequence to 50 Nm (37 ft. lbs.).
4.3. Tighten the engine flywheel bolts a final pass in sequence to 100 Nm (74 ft. lbs.).
5. Install the automatic transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Lamps and Indicators - Transmission and Drivetrain > Lamps
and Indicators - A/T > Shift Indicator > Component Information > Description and Operation
Shift Indicator: Description and Operation
The IPC displays the vehicle speed based on the vehicle speed signal from the PCM. The PCM
converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The IPC uses the
vehicle speed signal circuit from the PCM in order to calculate the vehicle speed. The speedometer
defaults to 0 km/h (0 mph) if a malfunction in the vehicle speed signal circuit exists.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Manual Transmission/Transaxle > Component Information >
Technical Service Bulletins > Manual Transmission - M/T Operating Characteristics
Manual Transmission/Transaxle: Technical Service Bulletins Manual Transmission - M/T Operating
Characteristics
INFORMATION
Bulletin No.: 03-07-29-004G
Date: December 15, 2010
Subject: Manual Transmission Operating Characteristics
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks (Including Saturn) 2009 and Prior
Chevrolet and GMC Medium Duty Trucks 2006-2010 HUMMER H3 with Manual Transmission
Supercede: This bulletin is being revised to add the 2011 model year and to add Cold Operation
information. Please discard Corporate Bulletin Number 03-07-29-004F (Section 07 Transmission/Transaxle).
Important Even though this bulletin attempts to cover operating characteristics of manual
transmissions, it cannot be all inclusive. Be sure to compare any questionable concerns to a similar
vehicle and if possible, with similar mileage. Even though many of the conditions are described as
characteristics and may not be durability issues, GM may attempt to improve specific issues for
customer satisfaction.
The purpose of this bulletin is to assist in identifying characteristics of manual transmissions that
repair attempts will not change. The following are explanations and examples of conditions that will
generally occur in all manual transmissions. All noises will vary between transmissions due to build
variation, type of transmission (usually the more heavy duty, the more noise), type of flywheel and
clutch, level of insulation, etc.
Basic Information
Many transmission noises are created by the firing pulses of the engine. Each firing pulse creates a
sudden change in angular acceleration at the crankshaft. These changes in speed can be reduced
with clutch damper springs and dual mass flywheels. However, some speed variation will make it
through to the transmission. This can create noise as the various gears will accel and decel against
each other because of required clearances.
Cold Operation
Manual transmission operation will be affected by temperature because the transmission fluid will
be thicker when cold. The thicker fluid will increase the amount of force needed to shift the
transmission when cold. The likelihood of gear clash will also increase due to the greater time
needed for the synchronizer assembly to perform its function. Therefore when the transmission is
cold, or before it has reached operating temperature, quick, hard shifts should be avoided to
prevent damage to the transmission.
Gear Rattle
Rattling or grinding (not to be confused with a missed shift type of grinding, also described as a
combustion knock type of noise) type noises usually occur while operating the engine at low RPMs
(lugging the engine). This can occur while accelerating from a stop (for example, a Corvette) or
while operating at low RPMs while under a load (for example, Kodiak in a lower gear and at low
engine speed). Vehicles equipped with a dual-mass flywheel (for example, a 3500 HD Sierra with
the 6-speed manual and Duramax(R)) will have reduced noise levels as compared to vehicles
without (for example, a 4500 Kodiak with the 6-speed manual and Duramax(R)). However,
dual-mass flywheels do not eliminate all noise.
Neutral Rattle
There are often concerns of rattle while idling in neutral with the clutch engaged. This is related to
the changes in angular acceleration described earlier. This is a light rattle, and once again, vehicles
with dual mass flywheels will have reduced noise. If the engine is shut off while idling in neutral with
the clutch engaged, the sudden stop of the engine will create a rapid change in angular
acceleration that even dual mass flywheels cannot compensate. Because of the mass of all the
components, this will create a noise. This type of noise should not be heard if the clutch is released
(pedal pushed to the floor).
Backlash
Backlash noise is created when changing engine or driveline loading. This can occur when
accelerating from a stop, coming to a stop, or applying and releasing the throttle (loading and
unloading the driveline). This will vary based on vehicle type, build variations, driver input, vehicle
loading, etc. and is created from the necessary clearance between all of the mating gears in the
transmission, axle(s) and transfer case (if equipped).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Manual Transmission/Transaxle > Component Information >
Technical Service Bulletins > Manual Transmission - M/T Operating Characteristics > Page 8124
Shift Effort
Shift effort will vary among different style transmissions and synchronizer designs. Usually the
more heavy duty the transmission, the higher the shift effort because of the increased mass of the
components. Shift effort can also be higher in cold weather because the fluid will be thicker.
Medium duty transmissions will not shift as quickly as a Corvette transmission. To reduce shift
effort, do not attempt to rush the shift - allow the synchronizers to work as designed. Shifting harder
will only increase the chance of rushing past the synchronizer leading to grinding while shifting.
Non-Synchronized Gears
Some light duty truck transmissions in 1st gear (creeper-gear) and reverse gears in various
transmissions, along with all gears in some medium duty transmissions, may be non-synchronized.
This means there is not a mechanism to match input and output shaft speeds to allow for a smooth
shift. This function is left up to the driver. This can be noticed if a shift into 1st or reverse is
attempted while the vehicle is rolling or before the input shaft stops rotating leading to a gear grind.
The grinding can be reduced by coming to a complete stop and pausing for a moment before
shifting into the 1st or reverse gear. Some slight grinding can be expected. In medium duty
non-synchronized transmissions, the driver must match input shaft (engine) speed to output shaft
(driveshaft) speed with every shift. This can be accomplished by double clutching, or by using other
methods. If the driver is not able to perform this function properly, there will be gear grinding with
each improperly completed shift. Driver training may be required to correct this condition. Clutch
brakes are used in medium duty non-synchronized transmissions to allow a shift into gear at a
stop. The clutch brake is used to stop the input shaft from spinning, allowing a shift into gear at a
stop without grinding. The clutch brake is activated by pressing the clutch pedal all the way to the
floor. When the clutch brake is used, it is possible to have a blocked shift with the vehicle
stationary. If this occurs, engage the clutch slightly to rotate the input gear to allow the shift. The
clutch brake is intended to only be used while at a stop. Care must be taken to not activate the
clutch brake while shifting between gears. This could lead to excessive grinding or a blocked or
missed shift.
Skip Shift
Currently, the Cadillac CTS-V, Pontiac GTO, Chevrolet Corvette and Camaro SS (other models
may follow) equipped with the 6-speed manual transmission have a feature referred to as a
"skip-shift." This feature only allows a shift from 1st to 4th gear when the indicator lamp is
illuminated on the dash. Dealers cannot disable this feature as it was established to help meet fuel
economy standards. The conditions for this feature are: engine coolant at normal operating
temperature, vehicle speed of 24-31 km/h (15-19 mph), 21% or less throttle being used (refer to
Service Information or the Owner Manual for more details.)
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Technical Service Bulletins >
Drivetrain - Transfer Case Control Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Technical Service Bulletins >
Drivetrain - Transfer Case Control Module Replacement > Page 8131
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1 > Page 8134
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift
Control Module - C1 > Page 8135
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 8136
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 8137
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Relays and Modules - Transmission and Drivetrain > Relays
and Modules - Transfer Case > Control Module, Transfer Case > Component Information > Diagrams > Page 8138
10. Start the engine and test the automatic transfer case system for proper shift operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > 4L60-E > Page
8146
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information > Diagrams > Page 8147
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 8152
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 8153
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 8154
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 8155
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information > Testing and Inspection >
4L60/4L60-E/4L65-E Transmission > Page 8156
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Diagrams > 4L60-E >
Page 8162
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Adjustments > 4L60-E
> Page 8165
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair >
4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair >
4L60-E > Page 8168
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair >
4L60-E > Page 8169
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component Information > Service and Repair >
4L60-E > Page 8170
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Diagrams > 4L60-E > Page
8176
Transmission Speed Sensor: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E >
Page 8179
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information > Service and Repair > 4L60-E >
Page 8180
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - A/T > Transmission Temperature Sensor/Switch, A/T > Component Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Technical Service
Bulletins > Customer Interest for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Technical Service
Bulletins > All Technical Service Bulletins for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case
Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams >
Transfer Case Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams >
Transfer Case Shift Control Switch - C1 > Page 8200
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Page
8201
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component Information > Diagrams > Page
8202
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Technical Service
Bulletins > Drivetrain - Updated Transfer Case Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Technical Service
Bulletins > Page 8207
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft
Speed Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft
Speed Sensor - Front > Page 8210
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic) > Page 8213
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic) > Page 8214
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic) > Page 8215
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic) > Page 8216
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Sensors and Switches - Transmission and Drivetrain >
Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component Information > Service and Repair >
NVG 149-NP (One Speed Automatic) > Page 8217
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Specifications
Transfer Case Actuator: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (14 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Diagrams > Front Axle Actuator
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Diagrams > Front Axle Actuator > Page 8225
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Diagrams > Front Axle Actuator > Page 8226
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Diagrams > Page 8227
Transfer Case Actuator: Service and Repair
Transfer Case Motor/Encoder Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the front propeller shaft. 4. Remove the motor/encoder electrical connectors.
5. Remove the motor/encoder mounting bolts. 6. Remove the motor/encoder assembly. 7. Remove
the motor/encoder gasket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Actuators and Solenoids - Transfer Case >
Transfer Case Actuator > Component Information > Diagrams > Page 8228
Important: ^
If the motor/encoder assembly is being replaced because it is defective, make sure that the transfer
case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench if
necessary.
^ When installing the motor/encoder unit to the transfer case, make sure that the transfer case is
indexed properly and it is flat against the transfer case before tightening the mounting bolts.
1. Install the NEW motor/encoder gasket to the transfer case. 2. Install the motor/encoder to the
transfer case.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install motor/encoder mounting bolts.
^ Tighten the bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
4. Install the motor/encoder electrical connector. Ensure that the retention clips activate. 5. Install
the front propeller shaft. 6. Install the transfer case shield. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Specifications
Case Adapter: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case to Transfer Case Adapter Nuts
...................................................................................................................................... 50 Nm (36 ft.
lbs.) Transfer Case Adapter to Transmission Bolts
...................................................................................................................................... 50 Nm (36 ft.
lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case to Transfer Case Adapter Nuts
...................................................................................................................................... 50 Nm (36 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Case Adapter: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Adapter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case from the vehicle. 3.
Support the transmission with a suitable jack stand.
4. Remove the rear crossmember from the frame.
5. Remove the mounting bolts from the adapter to the transmission. 6. Remove the adapter from
the transmission (automatic shown). 7. Remove the seal between the transfer case and the
adapter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8234
8. Remove the gasket from the adapter.
Installation Procedure
Important: Always use a new gasket and seal for the adapter. Do not use any type of sealant or
adhesive in place of or with the gasket or the seal.
1. Install the new seal on the adapter.
Important: The transfer case adapter must be installed so that the adapter is evenly seated to the
transmission before installing the retaining nuts.
2. Install the adapter to the transmission.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the adapter mounting bolts to the transmission.
^ Tighten the mounting bolts to 50 Nm (36 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8235
Important: When installing the gasket to the adapter, make sure that the yellow printing on the
gasket is facing toward the transfer case (away from the transmission). The locating tab on the
gasket should always be pointing up.
4. Install the new gasket to the adapter.
5. Install the transfer case to the adapter.
6. Install the crossmember in the vehicle.
^ Tighten the mounting bolts to 70 Nm (51 ft. lbs.).
7. Remove the transmission jack from the transmission. 8. Check the fluid level of the transfer
case. 9. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8236
Case Adapter: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Adapter Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case assembly. 3. Support the
transmission with a suitable jack stand.
4. Remove the transmission mount retaining nuts. 5. Raise the transmission assembly just high
enough to remove the transmission mount.
6. Remove the transmission support mounting bolts. 7. Remove the transmission support from the
frame.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8237
8. Remove the transmission mount bolts.
9. Remove the transmission mount.
10. Lower the transmission assembly slightly to gain access to the transfer case to the
transmission bolts.
11. Remove the transfer case adapter mounting bolts. 12. Remove the transfer case adapter. 13.
Remove the transfer case seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8238
14. Remove the transfer case gasket.
Installation Procedure
Important: If the gasket or the seal for the transfer case adapter becomes damaged, replace it. DO
NOT use any type of silicone sealer or liquid gasket maker in place of the seal or gasket.
1. Install the new transfer case adapter seal.
2. Install the transfer case adapter to the transmission.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the transfer case adapter mounting bolts.
^ Tighten the transfer case adapter mounting bolts to 50 Nm (34 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8239
4. Install the transmission mount.
5. Install the transmission mount bolts.
^ Tighten the transmission mount bolts to 47 Nm (35 ft. lbs.).
6. Install the transmission support to the frame. 7. Install the transmission support mounting bolts.
^ Tighten the transmission support mounting bolts to 70 Nm (51 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Case Adapter, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8240
8. Install the transmission mount retaining nuts.
^ Tighten the transmission mount retaining nuts to 40 Nm (29 ft. lbs.).
9. Remove the transmission jack from the transmission.
10. Install the new transfer case gasket. 11. Install the transfer case assembly. 12. Check the
transfer case fluid level. 13. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement > Page
8245
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Transfer Case Shift Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 8248
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 8249
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Page 8250
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Page 8251
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Control Module, Transfer Case >
Component Information > Diagrams > Page 8252
10. Start the engine and test the automatic transfer case system for proper shift operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Specifications > Capacity Specifications
Fluid - Transfer Case: Capacity Specifications
Transfer Case NVG 149 ......................................................................................................................
..................................................................................... 2.3L (2.4 Qt) NVG 236-246 ...........................
..............................................................................................................................................................
........... 1.9L (2.0 Qt)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Specifications > Capacity Specifications > Page 8257
Fluid - Transfer Case: Fluid Type Specifications
Transfer Case
NVG 149 ..............................................................................................................................................
..................... Auto-Trak II Fluid GM P/N 12378508
NVG 236/246
..........................................................................................................................................................
Auto-Trak II Fluid GM P/N 12378508
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Fluid - Transfer Case: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Fluid Replacement
Removal Procedure
Important: When performing the following service procedures, use only hand tools to remove and
install the fill or drain plugs.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shields from the cross
member (if equipped). 3. Remove the fill plug from the transfer case.
Important: When draining the transfer case, make sure that an approved drain pan is used.
4. Remove the drain plug from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8260
Important: If the drain or fill plug have to be replaced, used only aluminum replacement drain plugs.
1. Install the drain plug in the transfer case.
^ Tighten the drain plug to 20 Nm (15 ft. lbs.).
2. Fill the transfer case to the bottom of the fill hole with the proper fluid.
3. Install the fill plug.
^ Tighten the drain plug to 20 Nm (15 ft. lbs.).
4. Install the transfer case shield to the cross member. 5. Lower the vehicle. Refer to Vehicle
Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8261
Fluid - Transfer Case: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Fluid Replacement
Removal Procedure
Important: When performing the following service procedures, use only hand tools in order to
remove and install the fill or drain plugs. Always start the plugs by hand in order to prevent cross
threading.
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shields. 3. Remove the
transfer case fill plug.
4. Remove the transfer case drain plug.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Important: If the drain or fill plug have to be replaced, used only aluminum replacement drain plugs.
Steel plugs will react with the magnesium of
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Fluid - Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8262
the transfer case.
1. Install the transfer case drain plug.
^ Tighten the transfer case drain plug to 20 Nm (15 ft. lbs.).
2. Fill the transfer case to the bottom of the fill hole with the approved fluid. 3. Install the transfer
case fill plug.
^ Tighten the transfer case fill plug to 20 Nm (15 ft. lbs.).
4. Install the transfer case shield. 5. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Technical Service Bulletins > Customer Interest for Four Wheel Drive Selector Switch: >
02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Four Wheel Drive Selector
Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Diagrams > Transfer Case Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Diagrams > Transfer Case Shift Control Switch - C1 > Page 8278
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Diagrams > Page 8279
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Four Wheel Drive Selector Switch >
Component Information > Diagrams > Page 8280
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises
Output Shaft: Customer Interest Driveline - Bump/Clunk/Squawking Noises
Bulletin No.: 01-04-17-004B
Date: January 05, 2005
TECHNICAL
Subject: Clunk, Bump or Squawk when Vehicle Comes to Complete Stop or Accelerating from
Complete Stop (Replace Rear Drive Shaft Nickel-Plated Slip Yoke)
Models
Supercede:
This bulletin is being revised to add Cadillac Escalade (Old Style) to the Models section. Please
discard Corporate Bulletin Number 01-04-17-004A (Section 04 - Driveline/Axle).
Condition
Some customers may comment on a clunk, bump or squawk noise when the vehicle comes to a
stop or when accelerating from a complete stop.
Cause
A slip/stick condition between the transfer case output shaft and the driveshaft slip yoke may cause
this condition.
Diagnostic Tips
There are several resources in the electronic Service Information System which can provide the
technician with information on diagnosis and repair of clunk conditions, and fix the customer's
vehicle right the first time without unnecessary parts replacement. Some of the documents
available in SI include:
^ Symptoms - Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8289
^ Knock or Clunk Noise
^ Rear Drive Axle Noises (SI Document ID #700580)
^ Launch Shudder/Vibration on Acceleration (Replace Propeller Shaft and Install a New Pinion
Flange/Seal), Bulletin # 02-04-17-001
^ Information on 2-3 Upshift or 3-2 Downshift Clunk Noise, Bulletin # 01-07-30-042
^ Driveline Clunk When Stopping (Reprogram Powertrain Control Module (PCM), Bulletin #
03-07-30-028
Correction
Replace the rear drive shaft slip yoke with a new nickel-plated slip yoke. See the parts table below.
Follow the service procedure below.
1. Raise the vehicle on a hoist.
2. Reference mark the propeller shaft to the pinion flange connection.
Important:
Do not pound on the propeller shaft yoke ears. Never pry or place any tool between a yoke and a
universal joint.
3. Remove the bolts and the yoke retainers from the pinion flange.
4. Slide the propeller shaft forward and out of the rear pinion flange.
5. Lower the rear of the propeller shaft and pull the driveshaft out of the transfer case.
Note:
Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube causing an
imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
6. Support the propeller shaft in a line horizontal with the table of a press.
Important:
Remove the front slip yoke and the universal joint together. The new nickel-plated slip yoke comes
with a new universal joint.
7. Disassemble the snap rings by pinching the ends together with a pair of pliers.
8. If the ring does not readily snap out of the groove in the yoke, tap the end of the cup lightly in
order to relieve the pressure from the ring.
9. Place the universal joint so that the lower ear of the yoke is supported on a 30 mm (1-1/8 in) hex
head socket or a 27 mm (1-1/16 in) socket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8290
10. Place the J 9522-3 on the open horizontal bearing cups. Press the lower bearing cup out of the
yoke ear.
11. If you do not completely remove the bearing cup, lift the cross and insert the J 9522-5 between
the seal and the bearing cup you are removing. Continue pressing the bearing cup out of the yoke.
12. Rotate the propeller shaft. Press the opposite bearing cup out of the drive shaft yoke.
13. Remove the old slip yoke and universal joint.
14. Inspect the retaining ring grooves for dirt, corrosion, or pieces of the old ring.
15. Inspect the bearing cup bores for burrs or imperfections.
16. Clean the retaining ring grooves. Corrosion, dirt, rust, or pieces of the old retaining ring may
prevent the bearing cups from pressing into place or prevent the bearing retainers from properly
seating.
17. Install the new nickel-plated slip yoke and universal joint. See parts table below for parts
information.
18. Remove the bearing cups from the universal joint.
19. Assemble one bearing cup part way into one side of the yoke. Turn the yoke ear toward the
bottom.
20. Assemble the cross into the yoke so that the trunnion seats freely into the bearing cup.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8291
21. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until the
bearing cup is flush with the yoke ear.
22. Install the opposite bearing cup part way into the yoke ear.
23. Ensure that the trunnions start straight and true into both bearing cups.
24. Press the opposite bearing cup into the yoke ear while working the cross all the time in order to
inspect for free unbinding movement of the trunnions in the bearing cups.
Important:
If there seems to be a hang up or binding, stop pressing. Inspect the needle bearings for
misalignment in the bearing cup.
25. Press the bearing cup into the yoke until the bearing cup retainer groove is visible over the top
of the bearing cup.
26. Assemble the bearing retainer in the retainer groove.
27. Continue pressing until both retainers can be snapped into place.
28. If the retainer is difficult to seat, the yoke can be sprung slightly with a firm blow from a
soft-faced dead blow hammer.
29. It may be necessary to lubricate the snap ring with a slight amount of chassis grease so that
the snap ring seats in the bearing cup groove.
30. Install the slip yoke onto the output shaft in the transfer case.
31. Align the reference marks on the pinion flange and the propeller shaft.
32. Install the yoke retainers and bolts.
Tighten
Tighten the yoke retainer bolts to 25 N.m (19 lb ft).
33. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8292
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8293
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8294
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8295
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8296
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8297
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > Customer Interest: > 01-04-17-004B > Jan > 05 > Driveline Bump/Clunk/Squawking Noises > Page 8298
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises
Output Shaft: All Technical Service Bulletins Driveline - Bump/Clunk/Squawking Noises
Bulletin No.: 01-04-17-004B
Date: January 05, 2005
TECHNICAL
Subject: Clunk, Bump or Squawk when Vehicle Comes to Complete Stop or Accelerating from
Complete Stop (Replace Rear Drive Shaft Nickel-Plated Slip Yoke)
Models
Supercede:
This bulletin is being revised to add Cadillac Escalade (Old Style) to the Models section. Please
discard Corporate Bulletin Number 01-04-17-004A (Section 04 - Driveline/Axle).
Condition
Some customers may comment on a clunk, bump or squawk noise when the vehicle comes to a
stop or when accelerating from a complete stop.
Cause
A slip/stick condition between the transfer case output shaft and the driveshaft slip yoke may cause
this condition.
Diagnostic Tips
There are several resources in the electronic Service Information System which can provide the
technician with information on diagnosis and repair of clunk conditions, and fix the customer's
vehicle right the first time without unnecessary parts replacement. Some of the documents
available in SI include:
^ Symptoms - Propeller Shaft
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8304
^ Knock or Clunk Noise
^ Rear Drive Axle Noises (SI Document ID #700580)
^ Launch Shudder/Vibration on Acceleration (Replace Propeller Shaft and Install a New Pinion
Flange/Seal), Bulletin # 02-04-17-001
^ Information on 2-3 Upshift or 3-2 Downshift Clunk Noise, Bulletin # 01-07-30-042
^ Driveline Clunk When Stopping (Reprogram Powertrain Control Module (PCM), Bulletin #
03-07-30-028
Correction
Replace the rear drive shaft slip yoke with a new nickel-plated slip yoke. See the parts table below.
Follow the service procedure below.
1. Raise the vehicle on a hoist.
2. Reference mark the propeller shaft to the pinion flange connection.
Important:
Do not pound on the propeller shaft yoke ears. Never pry or place any tool between a yoke and a
universal joint.
3. Remove the bolts and the yoke retainers from the pinion flange.
4. Slide the propeller shaft forward and out of the rear pinion flange.
5. Lower the rear of the propeller shaft and pull the driveshaft out of the transfer case.
Note:
Never clamp propeller shaft tubing in a vise. Clamping could dent or deform the tube causing an
imbalance or unsafe condition. Always clamp on one of the yokes and support the shaft
horizontally. Avoid damaging the slip yoke sealing surface. Nicks may damage the bushing or cut
the lip seal.
6. Support the propeller shaft in a line horizontal with the table of a press.
Important:
Remove the front slip yoke and the universal joint together. The new nickel-plated slip yoke comes
with a new universal joint.
7. Disassemble the snap rings by pinching the ends together with a pair of pliers.
8. If the ring does not readily snap out of the groove in the yoke, tap the end of the cup lightly in
order to relieve the pressure from the ring.
9. Place the universal joint so that the lower ear of the yoke is supported on a 30 mm (1-1/8 in) hex
head socket or a 27 mm (1-1/16 in) socket.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8305
10. Place the J 9522-3 on the open horizontal bearing cups. Press the lower bearing cup out of the
yoke ear.
11. If you do not completely remove the bearing cup, lift the cross and insert the J 9522-5 between
the seal and the bearing cup you are removing. Continue pressing the bearing cup out of the yoke.
12. Rotate the propeller shaft. Press the opposite bearing cup out of the drive shaft yoke.
13. Remove the old slip yoke and universal joint.
14. Inspect the retaining ring grooves for dirt, corrosion, or pieces of the old ring.
15. Inspect the bearing cup bores for burrs or imperfections.
16. Clean the retaining ring grooves. Corrosion, dirt, rust, or pieces of the old retaining ring may
prevent the bearing cups from pressing into place or prevent the bearing retainers from properly
seating.
17. Install the new nickel-plated slip yoke and universal joint. See parts table below for parts
information.
18. Remove the bearing cups from the universal joint.
19. Assemble one bearing cup part way into one side of the yoke. Turn the yoke ear toward the
bottom.
20. Assemble the cross into the yoke so that the trunnion seats freely into the bearing cup.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8306
21. With the trunnion seated in the bearing cup, press the bearing cup into the yoke until the
bearing cup is flush with the yoke ear.
22. Install the opposite bearing cup part way into the yoke ear.
23. Ensure that the trunnions start straight and true into both bearing cups.
24. Press the opposite bearing cup into the yoke ear while working the cross all the time in order to
inspect for free unbinding movement of the trunnions in the bearing cups.
Important:
If there seems to be a hang up or binding, stop pressing. Inspect the needle bearings for
misalignment in the bearing cup.
25. Press the bearing cup into the yoke until the bearing cup retainer groove is visible over the top
of the bearing cup.
26. Assemble the bearing retainer in the retainer groove.
27. Continue pressing until both retainers can be snapped into place.
28. If the retainer is difficult to seat, the yoke can be sprung slightly with a firm blow from a
soft-faced dead blow hammer.
29. It may be necessary to lubricate the snap ring with a slight amount of chassis grease so that
the snap ring seats in the bearing cup groove.
30. Install the slip yoke onto the output shaft in the transfer case.
31. Align the reference marks on the pinion flange and the propeller shaft.
32. Install the yoke retainers and bolts.
Tighten
Tighten the yoke retainer bolts to 25 N.m (19 lb ft).
33. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8307
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8308
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8309
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8310
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8311
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8312
Parts Information
Parts are currently available from GMSPO.
Warranty Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 01-04-17-004B > Jan > 05 >
Driveline - Bump/Clunk/Squawking Noises > Page 8313
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 02-04-21-007 > Sep > 02 >
Drivetrain - New Transfer Case Output Bearing Tool
Output Shaft: All Technical Service Bulletins Drivetrain - New Transfer Case Output Bearing Tool
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-007
Date: September, 2002
INFORMATION
Subject: Release of New Tool J 45380 - Rear Output Shaft Bushing Remover and Installer
Models: 1998-2003 Light Duty Truck Models with AWD or 4WD and any of the following Transfer
Case Models: 126, 136, 149, 226, 233, 236, 246, 261 or 263 (Except 261 SHD or 263 SHD)
A new tool, J 45380, has been released to remove and install the rear output shaft bearing. The
following procedures may be used.
Identification
Identify the transfer case model as shown in the figure shown.
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Information.
2. Remove the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement in the
Transfer Case sub-section of the Service Information.
3. Remove the rear propeller shaft. Refer to Propeller Shaft Replacement - Rear in the Propeller
Shaft sub-section of the Service Information.
4. Remove the rear output shaft seal.
5. Inspect the rear output shaft bushing for scoring or wear.
6. Remove the rear output shaft bushing using the J 45380.
6.1. Install the finger section of the J 45380 in the front of the bushing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Output Shaft: > 02-04-21-007 > Sep > 02 >
Drivetrain - New Transfer Case Output Bearing Tool > Page 8318
6.2. Install the tube and forcing screw to the finger section. Ensure the forcing screw is backed out.
6.3. Using a wrench on the forcing screw, remove the rear output shaft bushing.
Installation Procedure
1. Using the J 45380, install a NEW rear output shaft bushing.
^ Install the bushing on the finger section of the J 45380.
^ Install the finger section of the J 45380.
^ Position the bushing and the tool to the case.
^ Using a hammer and J 45380, install the bushing.
2. Using the appropriate seal installer, install the rear output shaft seal in the transfer case.
3. Install the rear propeller shaft. Refer to Propeller Shaft Replacement - Rear in the Propeller Shaft
sub-section of the Service Information.
4. Verify the fluid level. Refer to Transfer Case Fluid Replacement.
5. Install the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement in the
Transfer Case sub-section of the Service Information.
6. Lower the vehicle.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Output Shaft: > 02-04-21-007 > Sep > 02 >
Drivetrain - New Transfer Case Output Bearing Tool
Output Shaft: All Technical Service Bulletins Drivetrain - New Transfer Case Output Bearing Tool
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-007
Date: September, 2002
INFORMATION
Subject: Release of New Tool J 45380 - Rear Output Shaft Bushing Remover and Installer
Models: 1998-2003 Light Duty Truck Models with AWD or 4WD and any of the following Transfer
Case Models: 126, 136, 149, 226, 233, 236, 246, 261 or 263 (Except 261 SHD or 263 SHD)
A new tool, J 45380, has been released to remove and install the rear output shaft bearing. The
following procedures may be used.
Identification
Identify the transfer case model as shown in the figure shown.
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Information.
2. Remove the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement in the
Transfer Case sub-section of the Service Information.
3. Remove the rear propeller shaft. Refer to Propeller Shaft Replacement - Rear in the Propeller
Shaft sub-section of the Service Information.
4. Remove the rear output shaft seal.
5. Inspect the rear output shaft bushing for scoring or wear.
6. Remove the rear output shaft bushing using the J 45380.
6.1. Install the finger section of the J 45380 in the front of the bushing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Output Shaft, Transfer Case > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Output Shaft: > 02-04-21-007 > Sep > 02 >
Drivetrain - New Transfer Case Output Bearing Tool > Page 8324
6.2. Install the tube and forcing screw to the finger section. Ensure the forcing screw is backed out.
6.3. Using a wrench on the forcing screw, remove the rear output shaft bushing.
Installation Procedure
1. Using the J 45380, install a NEW rear output shaft bushing.
^ Install the bushing on the finger section of the J 45380.
^ Install the finger section of the J 45380.
^ Position the bushing and the tool to the case.
^ Using a hammer and J 45380, install the bushing.
2. Using the appropriate seal installer, install the rear output shaft seal in the transfer case.
3. Install the rear propeller shaft. Refer to Propeller Shaft Replacement - Rear in the Propeller Shaft
sub-section of the Service Information.
4. Verify the fluid level. Refer to Transfer Case Fluid Replacement.
5. Install the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement in the
Transfer Case sub-section of the Service Information.
6. Lower the vehicle.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Technical Service Bulletins > Drivetrain - Transfer Case Control
Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Technical Service Bulletins > Drivetrain - Transfer Case Control
Module Replacement > Page 8330
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift Control Module - C1 > Page
8333
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Transfer Case Shift Control Module - C1 > Page
8334
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Page 8335
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Page 8336
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Relays and Modules - Transfer Case >
Control Module, Transfer Case > Component Information > Diagrams > Page 8337
10. Start the engine and test the automatic transfer case system for proper shift operation.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Seals and Gaskets: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Output Shaft Seal Replacement- Front
Transfer Case Output Shaft Seal Replacement- Front
^ Tools Required J 8092 Universal Handle
- J 43484 Front Output Shaft Seal Installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield from the
crossmember (if equipped). 3. Remove the front propeller shaft from the vehicle. 4. Insert a
Flat-tipped screwdriver in the inner race. 5. Pry the inner race back.
6. Insert a small pry bar in the inner race.
Important: When performing the following service procedure, the outer part of the seal will slightly
move out of the transfer case with the inner part seal.
7. Pry the inner part of the seal from the outer seal body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8342
8. Remove the inner part of the seal.
9. Insert a flat-tipped screwdriver or small pry bar in the space between the outer race of the seal
and the transfer easier.
10. Pry the outer race out of the transfer case.
11. Remove the outer part of the seal.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8343
1. Install the J 43484 (2) to the J 8092 (1). 2. Install the transfer case front input shaft on the J
43484. 3. Using the J 43484 (2) and the J 8092 (1), install the transfer case output seal. 4. Install
the front propeller shaft. 5. Check the transfer case fluid level. 6. Install the transfer case shield. 7.
Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Output Shaft Seal Replacement- Rear
Transfer Case Output Shaft Seal Replacement- Rear
^ Tools Required J 37668-A Seal Installer
- J 45380 Transfer Case Rear Bushing Remover and Installer
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield, if equipped. 3. Remove the rear propeller shaft. 4. Remove the rear output shaft seal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8344
5. Inspect the rear output shaft bushing for scoring or wear. 6. Remove the rear output shaft
bushing if required, using the J 45380.
^ Install the finger section of the J 45380 in front of the bushing.
^ Install the tube and forcing screw to the finger section. Ensure the forcing screw is backed out.
^ Using a wrench on the forcing screw, remove the rear output shaft bushing.
Installation Procedure
1. Using the J 45380, install a NEW rear output shaft bushing.
^ Install the bushing or the finger section of the J 45380.
^ Install the finger section of the J 45380.
^ Position the bushing and tool to the case.
^ Using a hammer and J 45380, install the bushing.
Important: Ensure the drain hole on the boot of the rear output shaft seal is facing down toward the
ground.
2. Using the J 37668-A, install the front output shaft in the transfer case. 3. Install the rear propeller
shaft.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8345
4. Check the fluid level. 5. Install the transfer case shield. 6. Lower the vehicle.
Transfer Case Input Shaft Seal Replacement
Transfer Case Input Shaft Seal Replacement
^ Tools Required J 42733 Seal Installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case from the adapter.
3. Remove the input shaft seal from the transfer case.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8346
Important: When installing the input shaft seal, make sure that the part numbers on the seal are
facing outward (toward the technician). The input shaft seal should be even with the surface of the
transfer case after installation.
1. Position the seal on the input shaft. 2. Using the J42738, install the input shaft seal in the
transfer case.
3. Install the transfer case to the adapter. 4. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8347
Seals and Gaskets: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Output Shaft Seal Replacement- Front
Transfer Case Output Shaft Seal Replacement- Front
^ Tools Required J 8092 Universal Handle
- J 43484 Front Output Shaft Seal Installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield from the
crossmember (if equipped). 3. Remove the front propeller shaft from the vehicle.
4. Insert a flat-tipped screwdriver in the inner race. 5. Pry the inner race back.
6. Insert a small pry bar in the inner race.
Important: When performing the following service procedure, the outer part of the seal will slightly
move out of the transfer case with the inner part seal.
7. Pry the inner part of the seal from the outer seal body.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8348
8. Remove the inner part of the seal.
9. Insert a flat-tipped screwdriver or small pry bar in the space between the outer race of the seal
and the transfer case.
10. Pry the outer race out of the transfer case.
11. Remove the outer part of the seal.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8349
1. Install the J 43484 (2) to the J 8092 (1). 2. Install the transfer case front input shaft seal on the J
43484. 3. Using the J 43484 (2) and the J 8092 (1), install the transfer case output seal. 4. Install
the front propeller shaft. 5. Check the transfer case fluid level. 6. Install the transfer case shield. 7.
Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Output Shaft Seal Replacement- Rear
Transfer Case Output Shaft Seal Replacement- Rear
^ Tools Required J 37668-A Seal Installer
- J 45380 Transfer Case Rear Bushing Remover and Installer
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the rear propeller shaft. 4. Remove the rear output shaft seal from the transfer
case.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8350
5. Inspect the rear output shaft bushing for scoring or wear. 6. Remove the rear output shaft
bushing if required, using the J 45380.
^ Install the finger section of the J 45380 in front of the bushing.
^ Install the tube and forcing screw to the finger section. Ensure the forcing screw is backed out.
^ Using a wrench on the forcing screw, remove the rear output shaft bushing.
Installation Procedure
1. Using the J 37668-A, install a NEW rear output shaft bushing.
^ Install the bushing or the finger section of the J 37668-A.
^ Install the finger section to the main body of the J 37668-A.
^ Position the bushing and tool to the case.
^ Using a hammer and J 37668-A, install the bushing.
Important: When installing the rear output shaft seal to the transfer case, ensure that the locator tab
is facing up.
2. Position the rear output shaft seal in the transfer case. 3. Using the J 37668-A, install the rear
output shaft to the transfer case. 4. Install the rear propeller shaft. 5. Inspect the transfer case fluid
level.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8351
6. Install the transfer case shield. 7. Lower the vehicle.
Transfer Case Input Shaft Seal Replacement
Transfer Case Input Shaft Seal Replacement
^ Tools Required J 42738 Seal Installer
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case assembly.
3. Remove the transfer case input shaft seal.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Seals and Gaskets, Transfer Case >
System Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8352
Important: When installing the input shaft seal, make sure that the part numbers on the seal are
facing outward (away from the body of the transfer case).
1. Align the transfer case input shaft seal evenly on the input shaft.
Important: The input shaft seal should be even with the surface of the transfer case after
installation.
2. Using the J 42738, install the transfer case input shaft seal.
3. Install the transfer case assembly in the vehicle. 4. Check the transfer case fluid level. 5. Lower
the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Technical Service Bulletins > Customer Interest for Four
Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Technical Service Bulletins > All Technical Service Bulletins
for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Diagrams > Transfer Case Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Diagrams > Transfer Case Shift Control Switch - C1 > Page
8369
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Diagrams > Page 8370
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Four Wheel Drive Selector Switch > Component Information > Diagrams > Page 8371
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Technical Service Bulletins > Drivetrain - Updated Transfer Case
Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Technical Service Bulletins > Page 8376
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft Speed Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Diagrams > Propshaft Speed Sensor - Front > Page 8379
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic) >
Page 8382
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic) >
Page 8383
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic) >
Page 8384
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic) >
Page 8385
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Sensors and Switches - Transfer Case >
Speed Sensor, Transfer Case > Component Information > Service and Repair > NVG 149-NP (One Speed Automatic) >
Page 8386
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Updated Transfer Case Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Page 8391
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front > Page 8394
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8397
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8398
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8399
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8400
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8401
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Specifications
Transfer Case Actuator: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (14 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Diagrams > Front Axle Actuator
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Diagrams > Front Axle Actuator > Page 8407
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Diagrams > Front Axle Actuator > Page 8408
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Diagrams > Page 8409
Transfer Case Actuator: Service and Repair
Transfer Case Motor/Encoder Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the front propeller shaft. 4. Remove the motor/encoder electrical connectors.
5. Remove the motor/encoder mounting bolts. 6. Remove the motor/encoder assembly. 7. Remove
the motor/encoder gasket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Actuator > Component
Information > Diagrams > Page 8410
Important: ^
If the motor/encoder assembly is being replaced because it is defective, make sure that the transfer
case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench if
necessary.
^ When installing the motor/encoder unit to the transfer case, make sure that the transfer case is
indexed properly and it is flat against the transfer case before tightening the mounting bolts.
1. Install the NEW motor/encoder gasket to the transfer case. 2. Install the motor/encoder to the
transfer case.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install motor/encoder mounting bolts.
^ Tighten the bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
4. Install the motor/encoder electrical connector. Ensure that the retention clips activate. 5. Install
the front propeller shaft. 6. Install the transfer case shield. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Clutch > Component
Information > Technical Service Bulletins > Transfer Case - 1st & 2nd Clutch Hub & Apply Plate
Transfer Case Clutch: Technical Service Bulletins Transfer Case - 1st & 2nd Clutch Hub & Apply
Plate
Bulletin No.: 05-04-21-005
Date: August 03, 2005
INFORMATION
Subject: First and Second Design Clutch Hub and Apply Plate for NV246 Transfer Case
Models: 1999-2004 Chevrolet Full Size Pickups and Utilities 1999-2004 GMC Full Size Pickups
and Utilities
with NV246 Transfer Case (RPO NP8)
If service requires replacement of the first design Clutch Hub (17) that is no longer available form
GMSPO ,the second design Clutch Hub (17) requires a second design Apply Plate (18) also be
replaced in order to obtain proper stack up height in the transfer case.
^ 1999-2002 vehicles that require replacement of the Clutch Hub (17), P/N 88962324 second
design also require the Apply Plate (18), P/N 88962331 second design to be replaced at the same
time in order to obtain proper stack up height in the transfer case.
^ 2003-2004 vehicles that require replacement of the Clutch Hub (17), P/N 88962324 second
design also require the Apply Plate (18), P/N 88962327 second design to be replaced at the same
time in order to obtaining proper stack up height in the transfer case.
Important:
^ A clutch plate shim package is necessary in order to have the proper shims available for setting
the correct clutch pack preload. Improper preload may cause driveability concerns and failure of
the transfer case.
^ Transfer case shims are available from GMSPO. Refer to Corporate Bulletin Number
04-04-21-003.
^ Whenever the second design Clutch Hub and the second design Apply Plate are used, a revised
stack height will have to be used. This implements a shim J-44295-4 (0.085 in. thick) in conjunction
with the clutch pack shimming kit J-44295 to achieve the correct stack height. Refer to SI Unit
Repair, Transfer Case Assemble.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Clutch > Component
Information > Technical Service Bulletins > Transfer Case - 1st & 2nd Clutch Hub & Apply Plate > Page 8415
Transfer Case Clutch: Technical Service Bulletins Drivetrain - Transfer Case Clutch Shimming
Bulletin No.: 04-04-21-003
Date: November 10, 2004
INFORMATION
Subject: Automatic Transfer Case Clutch Plate Shimming - Parts Availability Change
Models: 1999-2000 Cadillac Escalade 1998-2005 Chevrolet Blazer 1999-2005 Chevrolet Astro
Van, Silverado, Suburban, Tahoe 2002-2005 Chevrolet Avalanche 1998-2005 GMC Jimmy 1999
GMC Suburban 1999-2005 GMC Safari Van, Sierra, Yukon, Yukon XL 1998-2001 Oldsmobile
Bravada
with NV 136/236/246 Automatic Transfer Case (RPO NP4 or NP8)
While performing the transfer case clutch shimming procedure found in Service Information (SI),
you may find it necessary to replace the clutch pack selective fit shim to obtain the correct clutch
pack clearance.
The selective fit shims for this repair were previously released as a kit, P/N 12474121, which
contained all eight selective fit sizes. Effective immediately, the clutch pack shims will be available
individually as listed below. The shim kit, P/N 12474121, will be discontinued and no longer
available once current stock has been depleted.
Parts Information
Parts are currently available from GMSPO.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transfer Case > Transfer Case Mount > Component
Information > Specifications
Transfer Case Mount: Specifications
NVG 149-NP (One Speed Automatic)
Transmission Mount to Crossmember Nuts
.......................................................................................................................................... 40 Nm (29
ft. lbs.) Transmission Mount to Transfer Case Adapter Bolts
........................................................................................................................... 47 Nm (34 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transmission Mount to Crossmember Nuts
.......................................................................................................................................... 40 Nm (29
ft. lbs.) Transmission Mount to Transfer Case Adapter Bolts
........................................................................................................................... 47 Nm (34 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Specifications
Pressure Regulating Solenoid: Specifications
4L60-E
Pressure Control Solenoid Bracket to Valve Body Bolt .......................................................................
.......................................................................................................... 8.0-14.0 Nm (6-10 ft. lbs.)
4L80-E
Pressure Control Solenoid Bracket to Valve Body ..............................................................................
...................................................................................................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Diagrams > 4L60-E
Pressure Control Solenoid Valve Connector, Wiring Harness Side
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Diagrams > 4L60-E > Page 8427
Pressure Control Solenoid Valve Connector, Wiring Harness Side
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E
Pressure Regulating Solenoid: Service and Repair 4L60-E
Pressure Regulator Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
filter. 3. Compress the reverse boost valve sleeve into the bore of the oil pump to release tension
on the reverse boost valve retaining ring. 4. Remove the reverse boost valve retaining ring, then
slowly release tension on the reverse boost valve sleeve.
5. Remove the reverse boost valve sleeve (5) and the reverse boost valve (4). 6. Remove the
pressure regulator isolator spring (3) and the pressure regulator valve spring (2). 7. Remove the
pressure regulator valve (1).
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8430
1. Install the pressure regulator valve (1). 2. Install the pressure regulator isolator spring (3) and the
pressure regulator valve spring (2). 3. Install the reverse boost valve (4) in the reverse boost valve
sleeve (5). 4. Install the reverse boost valve (4) and sleeve (5) in the oil pump cover.
5. Compress the reverse boost valve sleeve into the bore of the oil pump to expose the retaining
ring slot. 6. Install the reverse boost valve retaining ring, then slowly release tension on the reverse
boost valve sleeve. 7. Install the transmission oil filter and pan. 8. Lower the vehicle. 9. Fill the
transmission to the proper level with DEXRON III transmission fluid. Refer to Transmission Fluid
Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8431
Pressure Regulating Solenoid: Service and Repair 4L80-E
Pressure Regulator Replacement
^ Tools Required J 36850 Transjel
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the reverse boost valve bushing retainer ring (2).
4. Remove the following from the reverse boost valve cylinder:
^ The reverse boost valve bushing
^ The reverse boost valve
^ The pressure regulator spring retainer
^ The pressure regulator spring
^ The pressure regulator valve
^ The reverse boost valve bushing
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Pressure Regulating Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8432
1. Install the pressure regulator valve with J 36850. 2. Pre-assemble the following parts:
^ The reverse boost valve bushing
^ A new reverse boost valve
^ A new pressure regulator spring retainer
^ The added isolator pressure regulator spring
^ The pressure regulator spring
3. Install the pre-assembled parts into the pump bore.
4. Install the reverse boost valve bushing retainer ring while holding the reverse boost valve
bushing in place.
Ensure the retainer ring (2) is in the groove.
5. Install the transmission oil pan and the oil filter. 6. Lower the vehicle. 7. Fill the transmission to
the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams > Page 8436
Shift Interlock Solenoid: Service and Repair
Automatic Transmission Shift Lock Actuator Replacement
Removal Procedure
Caution: Refer to SIR Caution in Service Precautions.
1. Disable the SIR system. 2. Remove the body control module bracket. 3. Put the shift lever clevis
into the neutral position. 4. Disconnect the electrical connector. 5. Use a small screwdriver to pry
the automatic transmission shift lock control actuator away from the steering column jacket
assembly and the cable
shift cam assembly.
6. Remove the automatic transmission shift lock control actuator.
Installation Procedure
1. Firmly install the automatic transmission shift lock control actuator onto the steering column
jacket assembly and the cable shift cam assembly. 2. Connect the electrical connector
3. Adjust the automatic transmission shift lock control actuator (with the shift lever clevis in the
neutral position) in the following way:
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Interlock Solenoid > Component Information >
Diagrams > Page 8437
3.1. Pull out the tab (1) on the adjuster block side (2) of the automatic transmission shift lock
control actuator.
3.2. Press on the adjuster block (2) to compress the internal adjuster spring, which disengages the
adjuster teeth. Slide the adjuster block (2) as far away from the actuator as possible.
3.3. Lock the adjuster block (2) in place by pushing in on the tab (1).
4. Inspect the automatic transmission shift lock control actuator for the following items:
4.1. The automatic transmission shift lock control actuator must lock the shift lever clevis when the
shift lever clevis is put into the park position.
4.2. Depress the brake pedal to move the shift lever out of the park position.
4.3. The actuator will be energized.
4.4. Readjust the automatic transmission shift lock control actuator if needed.
5. Install the body control module bracket. 6. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information >
Specifications
Shift Solenoid: Specifications
4L80-E
Solenoid to Valve Body .......................................................................................................................
............................................... 8 Nm (71 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
4L60-E
Shift Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
4L60-E > Page 8443
Shift Solenoid: Diagrams 4L80-E
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 8444
Shift Solenoid: Service and Repair
Control and Shift Solenoids Replacement
Removal Procedure
1. Remove the transmission oil pan and filter.
Important: Do not remove the valve body for the following procedures. Removal of the 1-2
accumulator is necessary only if servicing the pressure control solenoid.
2. Remove the 1-2 accumulator if necessary. 3. Disconnect the internal wiring harness electrical
connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
4. Remove the pressure control solenoid retainer. 5. Remove the pressure control solenoid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 8445
6. Remove the 1-2 and 2-3 shift solenoid retainers. 7. Remove the 1-2 and 2-3 shift solenoids.
8. Remove the 3-2 control solenoid retainer. 9. Remove the 3-2 control solenoid.
Installation Procedure
1. Install the 3-2 control solenoid. 2. Install the 3-2 control solenoid retainer.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 8446
3. Install the 1-2 and 2-3 shift solenoids. 4. Install the 1-2 and 2-3 shift solenoid retainers.
5. Install the pressure control solenoid. Ensure that the electrical tabs are facing outboard.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
7. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
8. Install the 1-2 accumulator. 9. Install the transmission oil pan and filter.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Shift Solenoid, A/T > Component Information > Diagrams >
Page 8447
10. Fill the transmission to the proper level with DEXRON III transmission fluid. Refer to
Transmission Fluid Checking Procedure.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Specifications
Torque Converter Clutch Solenoid: Specifications
4L60-E
TCC Solenoid Assembly to Case Bolt
..................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Diagrams > 4L60-E
Torque Converter Clutch Solenoid: Diagrams 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Diagrams > 4L60-E > Page 8453
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E
Torque Converter Clutch Solenoid: Service and Repair 4L60-E
Torque Converter Clutch Pulse Width Modulation (TCC PWM) Solenoid, TCC Solenoid, and Wiring
Harness
^ Tools Required J 28458 Seal Protector Retainer Installer
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and
the filter. 3. Disconnect the transmission harness 20-way connector from the transmission internal
harness pass-through connector.
Depress both tabs on the connector and pull straight up; do not pry the connector.
Important: Removal of the valve body is not necessary for the following procedure.
4. Remove the 1-2 accumulator assembly. Do not remove the spacer plate.
5. Disconnect the internal wiring harness electrical connectors from the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8456
6. Remove the TCC PWM solenoid retainer. 7. Remove the TCC PWM solenoid in order to access
one of the TCC solenoid retaining bolts.
8. Remove the pressure control solenoid retainer. 9. Remove the pressure control solenoid.
10. Remove the TCC solenoid retaining bolts and the valve body bolts, which retain the internal
wiring harness.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8457
11. Using J28458, release the pass-through electrical connector from the transmission case.
11.1. Use the small end of the J28458 over the top of the connector.
11.2. Twist in order to release the four tabs retaining the connector.
11.3. Pull the harness connector down through the transmission case.
12. Remove the TCC solenoid (with O-ring seal) and wiring harness assembly from the
transmission case.
13. Inspect the TCC solenoid and wiring harness assembly for the following defects:
^ Damage
^ Cracked connectors
^ Exposed wires
^ Loose pins
Installation Procedure
1. Install the wiring harness and TCC solenoid assembly with a new O-ring seal to the
transmission. 2. Install the pass-through electrical connector to the transmission case.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8458
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the valve body bolts, which retain the internal wiring harness and install the TCC solenoid
retaining bolts.
^ Tighten the control valve body retaining bolts to 11 Nm (97 inch lbs.).
^ Tighten the TCC solenoid retaining bolts to 11 Nm (97 inch lbs.).
4. Install the pressure control solenoid.
Ensure that the electrical tabs are facing outboard.
5. Install the pressure control solenoid retainer and retaining bolt.
^ Tighten the pressure control solenoid retaining bolt to 11 Nm (97 inch lbs.).
6. Install the TCC PWM solenoid to the control valve body. 7. Install the TCC PWM solenoid
retainer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8459
8. Connect the internal wiring harness electrical connectors to the following components:
^ Transmission fluid pressure switch (1)
^ 1-2 shift control solenoid (2)
^ 2-3 shift control solenoid (3)
^ Pressure control solenoid (4)
^ TCC PWM solenoid (5)
^ 3-2 control solenoid (6)
9. Install the 1-2 accumulator.
10. Connect the transmission harness 20-way connector to the transmission pass-through
connector.
Align the arrows on each half of the connector and insert straight down.
11. Install the transmission oil pan and filter. 12. Lower the vehicle. 13. Fill the transmission to the
proper level with DEXRON III transmission fluid. Refer to Transmission Fluid Checking Procedure.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8460
Torque Converter Clutch Solenoid: Service and Repair 4L80-E
Torque Converter Clutch (TCC) Valve and Spring Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transmission oil pan and the oil filter.
Caution: Valve springs can be tightly compressed. Use care when removing retainers and plugs.
Personal injury could result.
3. Remove the valve bore plug retainer ring (1).
4. Remove the following parts:
^ The valve bore plug
^ The TCC valve
^ The TCC valve spring
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - A/T > Torque Converter Clutch Solenoid, A/T > Component
Information > Service and Repair > 4L60-E > Page 8461
1. Install the following parts:
^ The TCC valve spring
^ The TCC valve
^ The valve bore plug
2. Install the valve bore plug retainer ring (1). 3. Install the transmission oil pan and oil filter. 4.
Lower the vehicle. 5. Fill the transmission to the proper level with DEXRON III transmission fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Specifications
Transfer Case Actuator: Specifications
NVG 149-NP (One Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (14 ft. lbs.)
NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Motor/Encoder Bolts
..................................................................................................................................................... 20
Nm (15 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator > Page 8468
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Front Axle Actuator > Page 8469
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Page 8470
Transfer Case Actuator: Service and Repair
Transfer Case Motor/Encoder Replacement
Removal Procedure
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case
shield. 3. Remove the front propeller shaft. 4. Remove the motor/encoder electrical connectors.
5. Remove the motor/encoder mounting bolts. 6. Remove the motor/encoder assembly. 7. Remove
the motor/encoder gasket.
Installation Procedure
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Actuators and Solenoids Transmission and Drivetrain > Actuators and Solenoids - Transfer Case > Transfer Case Actuator > Component Information
> Diagrams > Page 8471
Important: ^
If the motor/encoder assembly is being replaced because it is defective, make sure that the transfer
case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench if
necessary.
^ When installing the motor/encoder unit to the transfer case, make sure that the transfer case is
indexed properly and it is flat against the transfer case before tightening the mounting bolts.
1. Install the NEW motor/encoder gasket to the transfer case. 2. Install the motor/encoder to the
transfer case.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install motor/encoder mounting bolts.
^ Tighten the bolts, in the sequence shown, to 20 Nm (15 ft. lbs.).
4. Install the motor/encoder electrical connector. Ensure that the retention clips activate. 5. Install
the front propeller shaft. 6. Install the transfer case shield. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Lamps and Indicators Transmission and Drivetrain > Lamps and Indicators - A/T > Shift Indicator > Component Information > Description and
Operation
Shift Indicator: Description and Operation
The IPC displays the vehicle speed based on the vehicle speed signal from the PCM. The PCM
converts the data from the vehicle speed sensor to a 4000 pulses/mile signal. The IPC uses the
vehicle speed signal circuit from the PCM in order to calculate the vehicle speed. The speedometer
defaults to 0 km/h (0 mph) if a malfunction in the vehicle speed signal circuit exists.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement
Control Module: Technical Service Bulletins Drivetrain - Transfer Case Control Module
Replacement
Bulletin No.: 05-04-21-002
Date: March 10, 2005
INFORMATION
Subject: Guidelines for Replacement of Transfer Case Control Module (TCCM)
Models: 2005 and Prior Light Duty Trucks
with New Venture Gear (NVG) Transfer Case (RPOs NP1, NP4, NP8)
Dealers are replacing the TCCM unnecessarily.
Dealers are replacing the TCCM with codes stored in HISTORY only. The TCCM does not have a
current fault condition when tested.
Parts reviewed at the Warranty Parts Center (WPC) have a 75% No Trouble Found (NTF) rate.
The only two legitimate reasons to replace the TCCM are:
^ Diagnostic Trouble Code (DTC) C0550
^ NO Communication with a scan tool.
DTC C0550
This DTC indicates that the module has an internal fault and should be replaced.
No Communication
^ The no communication conditions referenced here are also caused by a module internal fault to a
point where the module physically will not talk. A technician cannot pull DTCs from the module
because it will not communicate. The module is electrically dead.
^ No communication is not to be confused with a U1026 code. This code tells the technician that
the module may still be functioning but is temporarily off line. This code may be set by the
Instrument Panel (IP) or the Powertrain Control Module (PCM) against the TCCM. The technician
needs to figure out why the module went off line. These are typically caused by connection
concerns. There is no need to replace a TCCM for a U1026 DTC.
Diagnostic Aids
^ When diagnosing a transfer case electrical control system, ALWAYS check power and ground
wiring first.
^ Test the connections for intermittent or poor connections, complete plug insertion, bent pins,
pushed out terminals and water contamination.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Transfer Case Control Module Replacement > Page 8483
Pay particular attention to the terminal connections at the module. Spread or open terminal
connections may create an intermittent contact. Do a pin drag test. Refer to the terminal testing
information in the table shown.
^ After repairs are complete, ALWAYS clear DTCs from the module prior to a system function test.
If codes are not cleared first, the system will not function after repair. The technician may
erroneously think that the system is still down and that further repairs are needed.
Warranty
Dealers who unnecessarily replace the TCCM that are found to have No Trouble Found (NTF) at
the WPC will be returned to the AVM (Area Service Manager), or the DSM (District Service
Manager) in Canada, through the Regional Feedback Process and may be charged back for the
repair through the WINS system.
Disclaimer
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1
Control Module: Diagrams Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 8486
Transfer Case Shift Control Module - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Transfer Case Shift Control Module - C1 > Page 8487
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 8488
Control Module: Service and Repair
Transfer Case Shift Control Module Replacement
Removal Procedure
1. Remove the IP trim bezel. 2. Pull out the lamp switch, 4WD shift buttons, cargo lamp and air
deflector louver assembly in order to disconnect the electrical connectors. 3. Disconnect all the
electrical connectors from the lamp switch, cargo lamp and 4WD shift buttons assembly. 4.
Remove the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly from the
vehicle.
5. Remove the electrical harness retainer from the IP support beam. 6. Disconnect the 2 electrical
connectors from the transfer case shift control module. 7. Move the electrical harness to the left
side in order to make room to turn the transfer case shift control module.
8. Rotate the transfer case shift control module about 45 degrees counter clockwise while pulling
out at the same time until the module is
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 8489
approximately 90 degrees from the original position.
9. Pull out the module from the vehicle.
Installation Procedure
1. Move the electrical harness to the left side in order to make room to install the transfer case shift
control module. 2. Install the transfer case shift control module so that the electrical connector ports
are to the right or pointing towards the instrument cluster. 3. While installing the transfer case shift
control module rotate clockwise until the module is in place and the electrical connector ports are
facing
outwards.
4. Install the electrical harness retainer to the IP support beam. 5. Connect the 2 electrical
connectors to the transfer case shift control module.
6. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver assembly the
vehicle. 7. Connect all the electrical connectors to the lamp switch, cargo lamp and 4WD shift
buttons assembly. 8. Install the lamp switch, 4WD shift buttons, cargo lamp and air deflector louver
assembly in place. 9. Install the IP trim bezel.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Relays and Modules Transmission and Drivetrain > Relays and Modules - Transfer Case > Control Module, Transfer Case > Component
Information > Diagrams > Page 8490
10. Start the engine and test the automatic transfer case system for proper shift operation.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Specifications
Fluid Pressure Sensor/Switch: Specifications
4L60-E
Transmission Fluid Pressure Manual Valve Position Switch to Valve .................................................
................................................................................................................................... 8.0-14.0 Nm
(6-10 ft. lbs.)
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > 4L60-E
A/T Fluid Pressure Manual Valve Position Switch Connector, Wiring Harness Side
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > 4L60-E > Page 8498
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Fluid Pressure Sensor/Switch, A/T > Component Information >
Diagrams > Page 8499
Fluid Pressure Sensor/Switch: Service and Repair
For information relating to service of this component please refer to Valve Body; Service And
Repair.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission
Transmission Mode Switch: Testing and Inspection 4L60/4L60-E/4L65-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body
control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control
module (PCM) to extend the length of time between upshifts and increase transmission line
pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to
a normal shift pattern.
Diagnostic Aids
If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 8504
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 8505
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 8506
Transmission Mode Switch: Testing and Inspection 4L80-E/4L85-E Transmission
Tow/Haul Switch/Indicator Always On or Inoperative
Circuit Description
Tow/haul mode enables the operator to achieve enhanced shift performance when towing or
hauling load. When tow/haul mode is selected, the tow/haul switch input signal to the body control
module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module
(PCM) to extend the length of time between upshifts and increase transmission line pressure.
Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal
shift pattern.
Diagnostic Aids
If the electrical circuit checks are OK and the tow/haul shift pattern is not occurring, there may be a
mechanical/hydraulic condition that prevents tow/haul operation. Refer to Symptoms - Automatic
Transmission.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 8507
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Mode Switch, A/T > Component Information >
Testing and Inspection > 4L60/4L60-E/4L65-E Transmission > Page 8508
Test Description
The numbers below refer to the step numbers on the diagnostic table. 2. This step tests for a faulty
tow/haul switch. 3. This step tests for voltage input from the BCM to the tow/haul switch. 6. This
step tests for voltage through the body wiring harness junction block. 7. This step tests for ground
integrity at the splice pack.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Specifications
Transmission Position Switch/Sensor: Specifications
4L60-E
Park/Neutral Position Switch Screw
.................................................................................................................................................... 3 Nm
(27 inch lbs.)
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Diagrams > 4L60-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Diagrams > 4L60-E > Page 8514
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Adjustments > 4L60-E
Transmission Position Switch/Sensor: Adjustments 4L60-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Adjustments > 4L60-E > Page 8517
Transmission Position Switch/Sensor: Adjustments 4L80-E
Park/Neutral Position Switch Adjustment
Important: ^
The following procedure is for vehicles that have not had the switch removed or replaced. If the
switch has been removed or replaced, refer to Park/Neutral Position Switch Replacement for the
proper adjustment procedure.
^ Apply the parking brake.
^ The engine must start in the P (Park) or N (Neutral) positions only.
^ Check the switch for proper operation. If adjustment is required, proceed as follows:
1. Place the transmission range selector in the N (Neutral) position. 2. With an assistant in the
drivers seat, raise the vehicle. Refer to Vehicle Lifting. 3. Loosen the park/neutral position switch
mounting bolts. 4. With the vehicle in the N (Neutral) position, rotate the switch while the assistant
attempts to start the engine. 5. Following a successful start, turn the engine off.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the bolts securing the switch to the transmission.
^ Tighten the bolts to 25 Nm (18 ft. lbs.).
7. Lower the vehicle. 8. Check the switch for proper operation. The engine must start in the P
(Park) or N (Neutral) positions only. 9. Replace the park/neutral position switch if proper operation
can not be achieved.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E
Transmission Position Switch/Sensor: Service and Repair 4L60-E
Park Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 8520
4. Position the tool J 41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 8521
Transmission Position Switch/Sensor: Service and Repair 4L80-E
Park/Neutral Position Switch Replacement
^ Tools Required J 41364-A Neutral Position Adjustment Tool
Removal Procedure
1. Apply the parking brake. 2. Shift the transmission into neutral. 3. Raise the vehicle. Refer to
Vehicle Lifting. 4. Remove the nut securing the transmission control lever to the manual shaft. 5.
Remove the transmission control lever from the manual shaft. 6. Disconnect the electrical
connectors from the switch. 7. Remove the bolts securing the park/neutral position switch to the
transmission. 8. Remove the park/neutral position switch from the manual shaft. If the park/neutral
position switch did not slide off the manual shaft, file the outer
edge of the manual shaft in order to remove any burrs.
Installation Procedure
1. Install the switch to the transmission manual shaft by aligning the switch hub flats with the
manual shaft flats. 2. Slide the switch onto the transmission manual shaft until the switch mounting
bracket contacts the mounting bosses on the transmission.
Important: If a new switch is being installed, the switch will come with a positive assurance bracket.
The positive assurance bracket aligns the new switch in it proper position for installation and the
use of neutral position adjustment tool will not be necessary.
3. Install the switch to the transmission with two bolts finger tight.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Position Switch/Sensor, A/T > Component
Information > Service and Repair > 4L60-E > Page 8522
4. Position the tool J41364-A onto the park/neutral position switch. Ensure that the two slots on the
switch where the manual shaft is inserted are
lined up with the lower two tabs on the tool.
Notice: Refer to Fastener Notice in Service Precautions.
5. Rotate the tool until the upper locator pin on the tool is lined up with the slot on the top of the
switch.
^ Tighten the bolts securing the switch to 25 Nm (18 ft. lbs.).
6. Remove the J 41364-A from the switch. If installing a new switch, remove the positive assurance
bracket at this time. 7. Connect the electrical connectors to the switch.
8. Install the transmission control lever to the manual shaft with the nut.
^ Tighten the control lever nut to 25 Nm (18 ft. lbs.).
9. Lower the vehicle.
10. Check the switch for proper operation. The engine must start in the P (Park) or N (Neutral)
positions only. If proper operation of the switch can
not be obtained, replace the switch.
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Specifications
Transmission Speed Sensor: Specifications
4L60-E
Speed Sensor Retainer Bolt
.................................................................................................................................................
10.5-13.5 Nm (7.7-10 ft. lbs.)
4L80-E
Speed Sensor and Bracket Assembly to Case
.................................................................................................................................... 11 Nm (97 inch
lbs.)
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Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Diagrams > 4L60-E
Vehicle Speed Sensor (VSS) Sensor Connector, Wiring Harness Side (4L60-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Diagrams > 4L60-E > Page 8528
Transmission Speed Sensor: Diagrams 4L80-E
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E
Transmission Speed Sensor: Service and Repair 4L60-E
Vehicle Speed Sensor (VSS) Replacement
Removal Procedure
1. Remove the harness connector. 2. Remove the bolt (2). 3. Remove the vehicle speed sensor
(1). 4. Remove the O-ring seal (3).
Installation Procedure
1. Install the O-ring seal (3) on the vehicle speed sensor (1). 2. Coat the O-ring seal (3) with a thin
film of transmission fluid. 3. Install the vehicle speed sensor (1) into the transmission case.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the bolt (2).
^ Tighten the bolt to 11 Nm (97 inch lbs.).
5. Connect the wiring harness electrical connector to the vehicle speed sensor. 6. Refill the fluid as
required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E > Page 8531
Transmission Speed Sensor: Service and Repair 4L80-E
Vehicle Speed Sensor (VSS) Replacement- Input
Vehicle Speed Sensor (VSS) Replacement- Input
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Disconnect the input speed sensor (1) electrical
connector. 3. Remove the input speed sensor bolt. 4. Remove the input speed sensor (1) and the
bracket assembly from the case. 5. Inspect the vehicle speed sensor assembly (1) for any
evidence of damage.
Installation Procedure.
1. Lubricate the input speed sensor seal with automatic transmission fluid. 2. Install the input speed
sensor (1) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the input speed sensor electrical connector. 5. Lower the vehicle.
Vehicle Speed Sensor (VSS) Replacement-Output
Vehicle Speed Sensor (VSS) Replacement-Output
Removal Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Speed Sensor, A/T > Component Information >
Service and Repair > 4L60-E > Page 8532
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: This procedure is for 2WD vehicles. If the vehicle is equipped with 4WD, the output
speed sensor is located on the transfer case.
2. Disconnect the output speed sensor (2) electrical connector. 3. Remove the output speed sensor
bolt. 4. Remove the output speed sensor (2) and the bracket assembly from the case. 5. Inspect
the output speed sensor assembly (2) for any evidence of damage.
Installation Procedure
1. Lubricate the output speed sensor seal with automatic transmission fluid. 2. Install the output
speed sensor (2) and the bracket assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolt.
^ Tighten the bolt to 11 Nm (96 inch lbs.).
4. Connect the output speed sensor electrical connector. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - A/T > Transmission Temperature Sensor/Switch, A/T > Component
Information > Diagrams
Transmission Fluid Temperature (TFT) Sensor Connector, Wiring Harness Side (4L80-E)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Technical Service Bulletins > Customer Interest for Four Wheel Drive Selector Switch: > 02-04-21-004 > Apr >
02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: Customer Interest Transfer Case Switch - `Service 4WD'
Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Four Wheel Drive Selector Switch: >
02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Transfer Case Shift Control Switch - C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Transfer Case Shift Control Switch - C1 > Page 8552
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Page 8553
Four Wheel Drive Selector Switch: Service and Repair
Transfer Case Shift Control Switch Replacement
Removal Procedure
1. Remove the instrument panel bezel trim piece.
2. Pull the tabs on the side of the transfer case driver control switch out. 3. Pull the transfer case
driver control switch straight out from the panel.
Installation Procedure
Important: Make sure that the transfer case control switch is seated properly in the instrument
panel before installing the instrument panel trim bezel.
1. Install the transfer case driver control switch into the instrument panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Four Wheel Drive Selector Switch > Component
Information > Diagrams > Page 8554
2. Install the instrument panel trim bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Drivetrain - Updated Transfer Case Speed Sensor Conn.
Speed Sensor: Technical Service Bulletins Drivetrain - Updated Transfer Case Speed Sensor
Conn.
Bulletin No.: 06-04-21-001
Date: May 17, 2006
INFORMATION
Subject: Updated Transfer Case Connector Service Kit Now Available For Transfer Case Speed
Sensor Wire Harness Connector that Comes Loose Or Connector Retainer Clip Breaks
Models: 2007 and Prior GM Light Duty Trucks 2007 and Prior HUMMER H2, H3 2005-2007 Saab
9-7X
with Four-Wheel Drive or All-Wheel Drive
Technicians may find that when the transfer case speed sensor wire harness connector is
removed, the connector lock flexes/bends and does not return to the original position. The transfer
case speed sensor wire harness connector then has no locking device. On older vehicles, the
plastic connector retainer becomes brittle and the clip may break as soon as it is flexed. In the past,
the only service fix was to install a wire harness connector service pack, P/N 88987183. This repair
procedure involved splicing a new service connector with an integral connector lock. This
connector service kit is of the same design and was still prone to failure over time.
A new connector service repair kit is now available, P/N 15306187, that is an updated design. This
new kit should be used whenever the speed sensor wire harness connector requires replacement.
Parts Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Technical Service Bulletins > Page 8559
Speed Sensor: Specifications
Transfer Case Speed Sensors ............................................................................................................
........................................................ 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Diagrams > Propshaft Speed Sensor - Front > Page 8562
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic)
Speed Sensor: Service and Repair NVG 149-NP (One Speed Automatic)
Transfer Case Speed Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the electrical connector from the speed
sensor.
3. Remove the speed sensor from the transfer case.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8565
1. Install the right rear speed sensor into the transfer case.
^ Tighten the right rear speed sensor to 31 Nm (23 ft. lbs.).
2. Install the electrical connector to the speed sensor. 3. Lower the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8566
Speed Sensor: Service and Repair NVG 236/246-NP8 (Two Speed Automatic)
Transfer Case Speed Sensor Replacement (Front)
Transfer Case Speed Sensor Replacement (Front)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case shield. 3. Remove the
transfer case front speed sensor electrical connector.
4. Remove the transfer case front speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8567
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case front speed sensor into the transfer case.
^ Tighten the transfer case front speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case front speed sensor electrical connector. 3. Install the transfer case
shield. 4. Lower the vehicle. Refer to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Right Rear)
Transfer Case Speed Sensor Replacement (Right Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8568
2. Remove the transfer case right rear electrical connector. 3. Remove the transfer case right rear
speed sensor.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case right rear speed sensor to the transfer case.
^ Tighten the transfer case right rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case right rear speed sensor electrical connector. 3. Lower the vehicle. Refer
to Vehicle Lifting.
Transfer Case Speed Sensor Replacement (Left Rear)
Transfer Case Speed Sensor Replacement (Left Rear)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the transfer case left rear speed sensor
electrical connector. 3. Remove the transfer case left rear speed sensor.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Transmission and Drivetrain > Transmission Control Systems > Sensors and Switches Transmission and Drivetrain > Sensors and Switches - Transfer Case > Speed Sensor, Transfer Case > Component
Information > Service and Repair > NVG 149-NP (One Speed Automatic) > Page 8569
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the transfer case left rear speed sensor into the transfer case.
^ Tighten the transfer case left rear speed sensor to 15 Nm (11 ft. lbs.).
2. Install the transfer case left rear speed sensor electrical connector. 3. Lower the vehicle. Refer to
Vehicle Lifting.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest: > 04-05-25-002E > Mar
> 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Electronic Brake Control Module: Customer Interest Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest: > 04-05-25-002E > Mar
> 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 8580
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: >
04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Electronic Brake Control Module: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins: >
04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 8586
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > All Other Service Bulletins for Electronic
Brake Control Module: > 02-04-21-004 > Apr > 02 > Transfer Case Switch - `Service 4WD' Indicator ON
Four Wheel Drive Selector Switch: All Technical Service Bulletins Transfer Case Switch - `Service
4WD' Indicator ON
File In Section: 04 - Driveline Axle
Bulletin No.: 02-04-21-004
Date: April, 2002
TECHNICAL
Subject: " "Service 4WD" Indicator Illuminated, DTC B2725 Set (Replace Transfer Case Shift
Control Switch)
Models: 1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Silverado, Sierra,
Avalanche, Suburban, Tahoe, Yukon, Yukon XL) with Four Wheel Drive and NVG 236/246
Transfer Case (RPO NP8)
Condition
Some customers may comment on the Service 4WD indicator illuminating. Upon investigation, the
technician may find DTC B2725 set.
Cause
The condition may be due to a intermittent fault in the transfer case shift control switch.
Correction
Important:
The transfer case shift control module should not need replacement. DO NOT replace P/N
15749703 unless diagnosis points to the module as the malfunction.
Replace the transfer case shift control switch using published Service Information procedures.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table shown.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Page 8597
Electronic Brake Control Module: Specifications
EBCM to BPMV Torx Bolts ..................................................................................................................
................................................. 5 Nm (39 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Technical Service Bulletins > Page 8598
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8601
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8602
Electronic Brake Control Module: Diagrams C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8603
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8604
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8605
Electronic Brake Control Module: Diagrams
C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8606
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8607
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8608
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Diagrams > C1 > Page 8609
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
Electronic Brake Control Module (EBCM) Replacement (w/o JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the electrical
connectors from the EBCM. 5. Loosen or remove 3 bolts (4) securing the EHCU mounting bracket
(3) to the frame rail (5).
6. Gently move the EHCU down enough to remove the four mounting screws that fasten the
EBCM(2) to the BPMV(1). 7. Remove the EBCM (2) from the BPMV (1). Removal may require a
light amount of force. 8. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
Important: Do not reuse the old mounting screws. Always install new mounting screws with the new
EBCM.
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
8612
1. Install the EBCM (2) on to the BPMV(1).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
3. Install or tighten three EHCU bracket mounting bolts.
Tighten the EHCU bracket mounting bolts to 25 Nm (18 ft. lbs.).
4. Connect the electrical connectors to the EBCM. 5. Lower the vehicle. 6. Connect the negative
battery cable. 7. Revise the tire calibration using the Scan Tool Tire Size Calibration function. 8.
Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
8613
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
(W/JL4)
Electronic Brake Control Module (EBCM) Replacement (w/ JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the brake fluid
pressure sensor (7) and pressure accumulator switch (4) electrical connectors.
5. Remove the four mounting screws that fasten the EBCM (2) to the BPMV (1). 6. Remove the
EBCM (2) from the BPMV (1). Removal may require a light amount of force.
Important: Note the routing of the jumper harnesses for reinstallation.
7. Remove the EBCM and jumper harnesses from the vehicle. 8. Remove the jumper harnesses
from the EBCM 9. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
1. Install the jumper harnesses to the EBCM. 2. Install the EBCM and jumper harnesses to the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Electronic
Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM) > Page
8614
Important: ^
Do not reuse the old mounting screws. Always install new mounting screws with the new EBCM.
^ Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
3. Install the EBCM (2) on to the BPMV (1).
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
5. Connect the brake fluid pressure sensor (7) and pressure accumulator switch (4) electrical
connectors. 6. Lower the vehicle. 7. Connect the negative battery cable. 8. Revise the tire
calibration using the Scan Tool Tire Size Calibration function. 9. Return to Diagnostic Starting Point
- Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Specifications
Hydraulic Control Assembly - Antilock Brakes: Specifications
Brake Pressure Modulator Bleeder Valves
............................................................................................................................................. 9 Nm (80
inch lbs.) EHCU Bracket to Frame Bolt ...............................................................................................
.................................................................... 25 Nm (18 ft. lbs.) EHCU to Bracket Allen Bolt ..............
.......................................................................................................................................................... 9
Nm (7 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4
Hydraulic Control Assembly - Antilock Brakes: Service and Repair W/ JL4
Brake Pressure Modulator Valve (BPMV) Replacement (w/ JL4)
Removal Procedure
Important: The area around the Electric Hydraulic Control Unit (EHCU) MUST be free from loose
dirt to prevent contamination of disassembled ABS components.
1. Thoroughly wash all contaminants from around the EHCU.
2. Disconnect the 2 electrical harness connectors from the Electronic Brake Control Module
(EBCM) (1).
3. Disconnect the electrical connector from the pressure accumulator switch.
4. Disconnect the electrical connector from the brake fluid pressure sensor.
Important: Make sure that brake lines are tagged and kept in order for proper reassembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8620
5. Disconnect the brake lines from the Brake Pressure Modulator Valve (BPMV) (2). 6. Remove the
bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5). 7. Remove the EHCU from
the vehicle.
8. Remove the bolts (4) securing the BPMV (1) to the EHCU mounting bracket (3). 9. Remove the
4 T-25 torx bolts from the EBCM (2).
10. Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.
11. Remove the accumulator switch.
12. Remove the brake fluid sensor (2).
Important: Do not reuse the EBCM mounting bolts. Always install new bolts.
13. Clean the EBCM to BPMV mounting surfaces with a clean cloth.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8621
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the pressure accumulator switch to the BPMV.
Tighten the switch to 3 Nm (30 inch lbs.).
2. Install the brake fluid pressure sensor (2) using a backup wrench to keep the brake fluid
pressure sensor collar (1) from turning.
Tighten the sensor to 16 Nm (12 ft. lbs.).
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
3. Install the EBCM (2) onto BPMV (1). 4. Install the four EBCM bolts.
Important: Do not reuse the old mounting bolts. Always install new EBCM bolts with the new
BPMV.
Tighten the bolts to 5 Nm (39 inch lbs.) in an X-pattern.
5. Connect the brake fluid pressure sensor and pressure accumulator switch electrical harnesses.
6. Install the BPMV (1) to EHCU bracket (3). 7. Install the BPMV to bracket retaining bolts (4).
Tighten the bolts to 9 Nm (7 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8622
8. Install the EHCU to the vehicle frame (5). 9. Install the EHCU bracket bolts.
Tighten the EHCU bracket bolts (4) to 25 Nm (18 ft. lbs.).
10. Connect the 2 electrical harness connectors to the EBCM (1).
Important: The brake pipes are held in place by a plastic bracket mounted to the frame. Make sure
that the brake pipes stay in the correct place for proper reassembly.
11. Install the brake pipes to the BPMV (2).
Tighten the brake pipe fittings to 25 Nm (18 ft. lbs.).
12. Bleed the brake system. 13. Bleed the brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8623
Hydraulic Control Assembly - Antilock Brakes: Service and Repair W/O JL4
Brake Pressure Modulator Valve (BPMV) Replacement (w/o JL4)
Removal Procedure
Important: The area around the electric hydraulic control unit (EHCU) MUST be free from loose dirt
to prevent contamination of disassembled ABS components.
1. Thoroughly wash all contaminants from around the EHCU.
2. Disconnect the 3 electrical harness connectors from the electronic brake control module (EBCM)
(1).
Important: Make sure that brake lines are tagged and kept in order for proper reassembly.
3. Disconnect the brake lines from the brake pressure modulator valve (BPMV) (2). 4. Remove the
bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5). 5. Remove the EHCU from
the vehicle.
6. Remove the bolts (4) securing the BPMV (1) to the EHCU mounting bracket (3). 7. Disconnect
the 2 way ABS pump motor connector. 8. Remove the 4 T-25 TORX bolts from the EBCM (2). 9.
Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.
Important: Do not reuse the EBCM mounting bolts. Always install new bolts.
10. Clean the EBCM to BPMV mounting surfaces with a clean cloth.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Hydraulic
Control Assembly - Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8624
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
1. Install the EBCM (2) onto BPMV (1).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the four EBCM bolts.
Important: Do not reuse the old mounting bolts. Always install new EBCM bolts with the new
BPMV.
Tighten the 4 bolts to 5 Nm (39 inch lbs.) in an X-pattern.
3. Connect the 2 way ABS pump motor connector to the EBCM. 4. Install the BPMV (1) to EHCU
bracket (3). 5. Install the BPMV (1) to bracket retaining bolts (4).
Tighten the bolts to 9 Nm (7 ft. lbs.).
6. Install the EHCU to the vehicle frame (5).
Tighten the three EHCU bracket bolts (4) to 25 Nm (18 ft. lbs.).
7. Connect the 2 electrical harness connectors to the EBCM (1).
Important: The brake pipes are held in place by a plastic bracket mounted to the frame. Make sure
that the brake pipes stay in the correct place for proper reassembly.
8. Install the 5 brake pipes to the BPMV (6).
Tighten the brake pipe fittings to 25 Nm (18 ft. lbs.).
9. Bleed the brake system.
10. Bleed the brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Module > Component Information > Diagrams
Inverting Driver Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Switch > Component Information > Locations
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Switch > Component Information > Locations > Page 8631
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak
Traction Control Switch: Service and Repair Stabilitrak
Traction Control Switch Replacement (Stabilitrak)
Removal Procedure
1. Remove Instrument Panel (IP) bezel.
2. Gently lift the retaining tabs (2) and remove the stabilitrak switch (3) from the instrument panel
(IP) assembly (1).
3. Disconnect the harness connector from the stabilitrak switch.
Installation Procedure
1. Connect the harness connector to the stabilitrak switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak > Page 8634
2. Install the stabilitrak switch (3) into the Instrument Panel (IP) assembly (1) 3. Ensure that the
switch is secure into both retaining tabs (2). 4. Install instrument panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Traction
Control Switch > Component Information > Service and Repair > Stabilitrak > Page 8635
Traction Control Switch: Service and Repair Traction Control
Traction Control Switch Replacement (Traction Control)
Removal Procedure
1. Remove instrument panel (IP) bezel.
2. Gently lift the switch retaining tabs (1) and remove the traction control switch (2) from the
Instrument Panel (IP) assembly (3). 3. Disconnect the harness connector from the traction control
switch.
Installation Procedure
1. Connect the harness connector to the traction control switch.
2. Install the traction control switch (2) into the instrument panel (IP) assembly (3), making sure that
all of the switch retaining tabs (1) are engaged. 3. Install Instrument Panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8644
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8645
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8646
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8647
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8648
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8649
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8650
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall - Possible Front
Wheel Speed Sensor Corrosion > Page 8651
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > NHTSA05V379000 > Aug > 05 > Recall
05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: Recalls Recall 05V379000: Wheel Speed Sensor Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8660
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8661
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8662
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8663
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8664
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8665
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8666
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8667
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front Wheel Speed
Sensor Corrosion > Page 8668
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May > 09 > Brakes
- Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: Customer Interest Brakes - Low Speed ABS Activation/No DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May > 09 > Brakes
- Low Speed ABS Activation/No DTC's Set > Page 8674
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 8680
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8685
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8686
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8687
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8688
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8689
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8690
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8691
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8692
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8701
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8702
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8703
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8704
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8705
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8706
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8707
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8708
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8709
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 8715
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8721
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8722
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8723
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8724
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8725
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8726
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8727
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 8728
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8737
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8738
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8739
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8740
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8741
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8742
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8743
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8744
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed Sensor: >
04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 8745
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Page 8746
Wheel Speed Sensor: Specifications
Front Wheel Speed Sensor Mounting Bolt
............................................................................................................................................... 18 Nm
(13 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Technical Service Bulletins > Page 8747
Wheel Speed Sensor - RF (4WD)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Diagrams > LF
Wheel Speed Sensor (WSS) - LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Diagrams > LF > Page 8750
Wheel Speed Sensor (WSS) - RF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Diagrams > Page 8751
Wheel Speed Sensor: Service and Repair
Wheel Speed Sensor Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the brake rotor (2). 4. Remove the Wheel Speed Sensor (WSS) mounting bolt.
Notice: Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a
screwdriver, or other device to pry the sensor out of the bore. Prying will cause the sensor body to
break off in the bore.
5. Remove the wheel speed sensor (5) from the hub/bearing assembly (4). 6. Remove the WSS
cable mounting clip from the knuckle. 7. Remove the WSS cable mounting clip from the upper
control arm. 8. Remove the WSS cable mounting clip from the frame attachment point. 9. Remove
the WSS cable electrical connector.
Installation Procedure
1. Install the WSS (5) into the hub/bearing assembly (4).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the WSS mounting bolt.
Tighten the WSS mounting bolt to 18 Nm (13 ft. lbs.).
3. Install the WSS cable mounting clip to the knuckle. 4. Install the WSS cable mounting clip to the
upper control arm. 5. Install the WSS cable mounting clip to the frame attachment point. 6. Connect
the WSS cable electrical connector. 7. Install the brake rotor (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Wheel Speed
Sensor > Component Information > Diagrams > Page 8752
8. Install the tire and wheel. 9. Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Yaw Rate
Sensor > Component Information > Specifications
Yaw Rate Sensor: Specifications
Yaw Rate Sensor/Lateral Accelerometer Nut
........................................................................................................................................ 10 Nm (89
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Antilock Brakes / Traction Control Systems > Yaw Rate
Sensor > Component Information > Specifications > Page 8756
Yaw Rate Sensor: Service and Repair
Yaw Rate Sensor/Lateral Accelerometer Replacement
Removal Procedure
1. Remove the front floor console bezel. 2. Disconnect the yaw rate sensor/lateral accelerometer
electrical connector.
3. Remove the 3 yaw rate sensor/lateral accelerometer nuts. 4. Remove the yaw rate sensor/lateral
accelerometer from the vehicle.
Installation Procedure
Important: Use care not to bend or distort the bracket that supports the yaw rate sensor/lateral
accelerometer.
1. Install the yaw rate sensor/lateral accelerometer to the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the 3 yaw rate sensor/lateral accelerometer nuts to the bracket.
Tighten the nuts to 10 Nm (89 inch lbs.).
3. Connect the yaw rate sensor/lateral accelerometer electrical connector. 4. Install the front floor
bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure
Brake Bleeding: Service and Repair ABS Automated Bleed Procedure
W/JL4
ABS Automated Bleed Procedure (W/JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure is ONLY to be performed on vehicles equipped with option code JL4,
Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this bleeding
procedure. If you have not yet performed the base hydraulic brake system bleeding procedure,
refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool. 2. Apply the park brake fully. 3. Start the engine and allow the engine to idle.
4. Depress the brake pedal firmly and maintain steady pressure on the pedal. 5. From the VSES
Special Functions menu on the scan tool, select the Automated Bleed procedure. 6. Send the
automated bleed command by pressing the On key on the scan tool.
After initiating the automated bleed procedure, the brake pedal will drop and then pulse back up, 8
times, while the LPA is being purged of any trapped air.
7. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT 3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half full during this bleeding procedure and add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm, when cap removal is necessary.
8. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 9.
Install a transparent hose over the end of the bleeder valve.
10. Submerge the open end of the transparent hose into a transparent container partially filled with
Delco Supreme II, GM P/N 12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
11. Have an assistant slowly depress the brake pedal and maintain pressure on the pedal. 12.
Loosen the bleeder valve to purge air from the wheel hydraulic circuit. 13. Tighten the bleeder
valve when full brake pedal travel has occurred. 14. Have the assistant slowly release the brake
pedal. Wait 5 seconds before proceeding to the next step. 15. Repeat steps 11-14 until all air is
purged from the same wheel hydraulic circuit. 16. After all air has been purged from the right rear
hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end wrench onto
the LEFT REAR wheel hydraulic circuit bleeder valve.
17. Repeat steps 9-15 at the left rear wheel hydraulic circuit. 18. After all air has been purged from
the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end
wrench onto
the RIGHT FRONT wheel hydraulic circuit bleeder valve.
19. Repeat steps 9-15 at the right front wheel hydraulic circuit. 20. After all air has been purged
from the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper
box-end wrench onto
the LEFT FRONT wheel hydraulic circuit bleeder valve.
21. Repeat steps 9-15 at the left front wheel hydraulic circuit. 22. Fill the brake master cylinder
reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
23. Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
24. Install a transparent hose over the end of the bleeder valve. 25. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
26. Use the procedure below to purge the Medium Pressure Accumulator (MPA) of any trapped air.
26.1. With the engine still idling, select the Bleed MPA procedure from the VSES Special Functions
menu.
26.2. Send the bleed MPA command by pressing the On key on the scan tool.
26.3. Open the LEFT FRONT wheel hydraulic circuit bleeder valve.
Important: Ensure that you fully release the brake pedal for at least 2 seconds between pedal
strokes. The amount of accumulated time between pedal strokes is calculated to deliver the most
thorough bleed of the Medium Pressure Accumulator (MPA).
26.4. Depress the brake pedal as far as possible using a smooth stroke.
26.5. Release the brake pedal using a smooth stroke.
26.6. Repeat steps 26.4-26.5 until 13 complete pedal strokes have been performed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure > Page 8761
Important: Observe the MPA switch parameter as the pedal strokes are being performed. The MPA
switch parameter should change from Uncharged to Charged several times during the first 8 or 9
strokes. After approximately 10 pedal strokes, the MPA switch parameter should remain Charged.
If the parameter does not change, repeat all of step 26.
26.7. The valves within the BPMV are active for the first 13 complete pedal strokes to enable the
MPA to be filled and discharged, forcing any trapped air out of the LEFT FRONT wheel hydraulic
circuit bleeder valve.
26.8. Continue to depress and release the brake pedal while observing the fluid within the
transparent hose. When no air is observed exiting the hydraulic system, proceed to the next step.
26.9. Depress the brake pedal and maintain pedal position.
26.10. Have an assistant tighten the bleeder valve.
26.11. Release the brake pedal.
27. Remove the scan tool from the vehicle. 28. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
29. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 30. If the
brake pedal feels spongy, repeat this entire bleed procedure. If the brake pedal still feels spongy
after repeating this procedure, inspect the
brake system for external leaks.
31. Observe the brake warning indicator to determine whether or not the indicator remains
illuminated. 32. If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to
be driven until it is diagnosed and repaired.
W/O JL4
ABS Automated Bleed Procedure (w/o JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure may be performed on all vehicles EXCEPT those equipped with option
code JL4, Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this automated
bleeding procedure. If you have not yet performed the base hydraulic brake system bleeding
procedure, refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool to the vehicle. 2. Start the engine and allow the engine to idle. 3. Depress the
brake pedal firmly and maintain steady pressure on the pedal. 4. Using the scan tool, begin the
automated bleed procedure. 5. Follow the instructions on the scan tool to complete the automated
bleed procedure. Release the brake pedal between each test sequence. 6. Turn the ignition OFF.
7. Remove the scan tool from the vehicle. 8. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
9. Bleed the hydraulic brake system.
10. With the ignition OFF, apply the brakes 3-5 times, or until the brake pedal becomes firm, in
order to deplete the brake booster power reserve. 11. Slowly depress and release the brake pedal.
Observe the feel of the brake pedal. 12. If the brake pedal feels spongy, repeat the automated
bleeding procedure. If the brake pedal still feels spongy after repeating the automated
bleeding procedure inspect the brake system for external leaks.
13. Turn the ignition key ON, with the engine OFF; check to see if the brake system warning lamp
remains illuminated. 14. If the brake system warning lamp remains illuminated, DO NOT allow the
vehicle to be driven until it is diagnosed and repaired. Refer to
Symptoms - Hydraulic Brakes.
15. Drive the vehicle to exceed 13 kPa (8 mph) to allow ABS initialization to occur. Observe brake
pedal feel. 16. If the brake pedal feels spongy, repeat the automated bleeding procedure until a
firm brake pedal is obtained.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure > Page 8762
Brake Bleeding: Service and Repair Hydraulic Brake System Bleeding
Manual
Hydraulic Brake System Bleeding (Manual)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder - after all air has been
purged from the front port of the master cylinder- loosen and separate the rear brake pipe from the
master cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT-3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm.
5. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 6.
Install a transparent hose over the end of the bleeder valve. 7. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
8. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal. 9. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
10. Tighten the bleeder valve, then have the assistant slowly release the brake pedal. 11. Wait 15
seconds, then repeat steps 8-10 until all air is purged from the same wheel hydraulic circuit. 12.
With the right rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been
purged from the right rear hydraulic circuit install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
13. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 14. With
the left rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the left rear hydraulic circuit- install a
proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
15. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 16. With
the right front wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
17. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 18. After
completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel
hydraulic circuit bleeder valves are properly
tightened.
19. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
20. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 21. If the
brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy
after repeating the bleeding procedure,
perform the following steps: 21.1.
Inspect the brake system for external leaks.
21.2. Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped
in the system.
22. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure > Page 8763
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
23. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Pressure
Hydraulic Brake System Bleeding (Pressure)
Tools Required ^
J29532 Diaphragm Type Brake Pressure Bleeder, or equivalent
^ J35589-A Brake Pressure Bleeder Adapter
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder- after all air has been purged
from the front port of the master cylinder - loosen and separate the rear brake pipe from the master
cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Clean the outside of the
reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
5. Install the J35589-A to the brake master cylinder reservoir. 6. Check the brake fluid level in the
J29532, or equivalent. Add Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3
brake fluid from a clean, sealed brake fluid container as necessary to bring the level to
approximately the half-full point.
7. Connect the J29532, or equivalent, to the J35589-A. 8. Charge the J29532, or equivalent, air
tank to 175 - 205 kPa (25 - 30 psi). 9. Open the J29532, or equivalent, fluid tank valve to allow
pressurized brake fluid to enter the brake system.
10. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to
ensure that there are no existing external brake fluid
leaks. Any brake fluid leaks identified require repair prior to completing this procedure.
11. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
12. Install a transparent hose over the end of the bleeder valve. 13. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
14. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air
bubbles stop flowing from the bleeder, then
tighten the bleeder valve.
15. With the right rear wheel hydraulic circuit bleeder valve tightened securely - after all air has
been purged from the right rear hydraulic circuitinstall a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
16. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 17. With
the left rear wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the left rear hydraulic circuit- install
a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
18. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 19. With
the right front wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
20. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure > Page 8764
21. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4
wheel hydraulic circuit bleeder valves are properly
tightened.
22. Close the J29532, or equivalent, fluid tank valve, then disconnect the J29532, or equivalent,
from the J35589-A. 23. Remove the J35589-A from the brake master cylinder reservoir. 24. Fill the
brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967
(Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
25. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 26. If the
brake pedal feels spongy perform the following steps:
26.1. Inspect the brake system for external leaks.
26.2. Using a scan tool, perform the antilock brake system automated bleeding procedure to
remove any air that may have been trapped in the BPMV.
27. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
28. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Bleeding > System Information > Service and Repair >
ABS Automated Bleed Procedure > Page 8765
Brake Bleeding: Service and Repair Master Cylinder Bench Bleeding
Master Cylinder Bench Bleeding
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
1. Secure the mounting flange of the brake master cylinder in a bench vise so that the rear of the
primary piston is accessible. 2. Remove the master cylinder reservoir cap and diaphragm. 3. Install
suitable fittings to the master cylinder ports that match the type of flare seat required and also
provide for hose attachment. 4. Install transparent hoses to the fittings installed to the master
cylinder ports, then route the hoses into the master cylinder reservoir. 5. Fill the master cylinder
reservoir to at least the half-way point with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent
DOT-3 brake fluid from a clean, sealed brake fluid container.
6. Ensure that the ends of the transparent hoses running into the master cylinder reservoir are fully
submerged in the brake fluid. 7. Using a smooth, round-ended tool, depress and release the
primary piston as far as it will travel, a depth of about 25 mm (1 inch), several times.
Observe the flow of fluid coming from the ports. As air is bled from the primary and secondary
pistons, the effort required to depress the primary piston will increase and the amount of travel will
decrease.
8. Continue to depress and release the primary piston until fluid flows freely from the ports with no
evidence of air bubbles. 9. Remove the transparent hoses from the master cylinder reservoir.
10. Install the master cylinder reservoir cap and diaphragm. 11. Remove the fittings with the
transparent hoses from the master cylinder ports. Wrap the master cylinder with a clean shop cloth
to prevent brake
fluid spills.
12. Remove the master cylinder from the vise.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Pedal Assy > Component Information > Specifications
Brake Pedal Assy: Specifications
Brake Pedal Bolt ..................................................................................................................................
..................................................... 47 Nm (35 ft. lbs.) Brake Pedal Maximum Travel .................
Specification with 445 N (100 lbs) of force applied to the brake pedal, the ignition OFF, and the
brake booster
power reserve depleted.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Pedal Assy > Component Information > Specifications
> Page 8769
Brake Pedal Assy: Service and Repair
Brake Pedal Replacement
Removal Procedure
1. Remove the pushrod retaining clip (4). 2. Remove the stoplamp switch (2) and the pushrod (3)
from the brake pedal stud (1).
3. Remove the nut from the brake pedal bolt. 4. Remove the brake pedal bolt. 5. Remove the brake
pedal.
Installation Procedure
1. Install the brake pedal. 2. Install the brake pedal bolt.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Pedal Assy > Component Information > Specifications
> Page 8770
3. Install the nut to the brake pedal bolt.
Hold the nut with a wrench and tighten the brake pedal bolt to 47 Nm (35 ft. lbs.).
4. Install the pushrod (3) and the stoplamp switch (2) to the brake pedal pin (1). 5. Install the
pushrod retaining clip (4).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Brake Warning Indicator > Component Information > Testing
and Inspection
Brake Warning Indicator: Testing and Inspection
For information regarding this component and the system that it is a part of, please refer to
Hydraulic System Testing and Inspection.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement
Brake Caliper: Service and Repair Brake Caliper Bracket Replacement
Front
Brake Caliper Bracket Replacement - Front
Removal Procedure
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
1. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
2. Remove the brake pads. 3. Remove the anti-rattle clips from the brake caliper bracket.
4. Remove the brake caliper bracket mounting bolts (2). 5. Remove the brake caliper bracket (1). 6.
Remove any contaminants or foreign material from the inside ends of the brake caliper bracket. 7.
Clean the mounting surface and threads of the brake caliper bracket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8779
1. Install the brake caliper bracket (1). 2. Perform the following procedure before installing the
brake caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the caliper bracket mounting bolts (2).
^ Tighten the brake caliper bracket to knuckle bolt to 175 Nm (121 ft. lbs.) for the 15 Series.
^ Tighten the brake caliper bracket to knuckle bolts to 300 Nm (221 ft. lbs.) for 25 Series.
4. Install the anti-rattle clips to the brake caliper bracket. 5. Install the brake pads to the brake
caliper bracket.
^ Install the inner pad-1 wear indicator.
^ Install the inner pad-2 wear indicators.
6. Slide the brake pads in until they contact the rotor. 7. Install the brake caliper. 8. Install the tire
and wheel assembly. 9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance. 11. Slowly release the brake pedal. 12. Wait 15 seconds, then repeat steps 1-11 until a
firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Rear
Brake Caliper Bracket Replacement - Rear
Removal Procedure
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8780
1. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
2. Remove the brake pads. 3. Remove the anti-rattle clips from the brake caliper bracket.
4. Remove the brake caliper bracket mounting bolts (2). 5. Remove the brake caliper bracket (1). 6.
Remove any contaminants or foreign material from the inside ends of the brake caliper bracket. 7.
Clean the mounting surface and threads of the brake caliper bracket.
Installation Procedure
1. Install the brake caliper bracket (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8781
2. Perform the following procedure before installing the brake caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the caliper bracket mounting bolts (2).
^ For vehicles equipped with JC5/JH5 brake systems, tighten the caliper bracket mounting bolts to
200 Nm (148 ft. lbs.).
^ For vehicles equipped with JH6 brake systems, tighten the caliper bracket mounting bolts to 165
Nm (122 ft. lbs.).
4. Install the anti-rattle clips to the brake caliper bracket. 5. Install the brake pads to the brake
caliper bracket. 6. Slide the brake pads in until they contact the rotor. 7. Install the brake caliper. 8.
Install the tire and wheel assembly. 9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance. 11. Slowly release the brake pedal. 12. Wait 15 seconds, then repeat steps 7-8 until a
firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8782
Brake Caliper: Service and Repair Brake Caliper Overhaul
Front
Brake Caliper Overhaul - Front
Disassembly Procedure
Caution: Do not place your fingers in front of the piston in order to catch or protect the piston while
applying compressed air. This could result in serious injury.
1. Remove the brake caliper from the vehicle.
2. Place a thin piece of wood in front of the piston in order to prevent damage. Remove the piston
by directing compressed air into the brake hose
inlet fitting port of the brake caliper housing.
3. Remove the piston boot. 4. Remove the piston seal. 5. Remove the brake caliper bleed screw
cap. 6. Remove the brake caliper bleed screw. 7. Inspect the brake caliper bore and the piston seal
groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston
seal area, replace the brake caliper housing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8783
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and
replace the brake caliper mounting bracket if
necessary.
9. Clean all of the residue from the brake pad guiding surfaces on the brake caliper housing and
the brake caliper mounting bracket.
10. Clean all of the parts not included in the repair kit with denatured alcohol. 11. Dry all of the
parts with filtered Unlubricated compressed air. 12. Blow out all passages in the brake caliper
housing and the brake caliper bleeder valve.
Assembly Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper bleed screw.
Tighten the brake caliper bleed screw to 12 Nm (106 inch lbs.).
2. Install the brake caliper bleed screw cap. 3. Lubricate the new piston seals and the brake caliper
bore seal grooves with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 4. Install new seals
into the brake caliper bore seal grooves. 5. Ensure that the seals are not twisted. 6. Lubricate the
brake caliper bores and the pistons with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 7.
Install the boot and piston.
7.1. Install the boot over the end of the piston so that the fold will face toward the brake caliper
housing piston bore opening.
7.2. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore.
7.3. Push down the piston to the bottom of the brake caliper bore.
7.4. Ensure the boot seats properly into the piston groove and into the groove in the brake caliper
bore.
7.5. Repeat steps 5 and 6 for the remaining piston.
8. Install the brake caliper to the vehicle.
Rear
Brake Caliper Overhaul - Rear
Disassembly Procedure
Caution: Do not place your fingers in front of the piston in order to catch or protect the piston while
applying compressed air. This could result in serious injury.
1. Remove the brake caliper from the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8784
2. Place a thin piece of wood in front of the piston in order to prevent damage. Remove the piston
by directing compressed air into the brake hose
inlet fitting port of the brake caliper housing.
3. Remove the piston boot. 4. Remove the piston seal. 5. Remove the brake caliper bleed screw
cap. 6. Remove the brake caliper bleed screw. 7. Inspect the brake caliper bore and the piston seal
groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston
seal area, replace the brake caliper housing.
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and
replace the brake caliper mounting bracket if
needed.
9. Clean all the residue from the brake pad guiding surfaces on the brake caliper housing and the
brake caliper mounting bracket.
10. Clean all the parts not included in the repair kit with denatured alcohol. 11. Dry all the parts with
filtered Unlubricated compressed air. 12. Blow out all passages in the brake caliper housing and
the brake caliper bleeder valve.
Assembly Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8785
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper bleed screw.
Tighten the brake caliper bleed screw to 12 Nm (106 inch lbs.).
2. Install the brake caliper bleed screw cap. 3. Lubricate the new piston seal and the brake caliper
bore seal groove with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 4. Install new the
seal into the brake caliper bore seal groove. 5. Ensure that the seal is not twisted. 6. Lubricate the
brake caliper bore and the piston with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 7.
Install the boot and the piston.
7.1. Install the boot over the end of the piston so that the fold will face toward the brake caliper
housing piston bore opening.
7.2. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore.
7.3. Push down the piston to the bottom of the brake caliper bore.
7.4. Ensure that the boot properly seats into the piston groove and into the groove in the brake
caliper bore.
7.5. Repeat steps 5 and 6 for the remaining piston.
8. Install the brake caliper to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8786
Brake Caliper: Service and Repair Brake Caliper Replacement
Front
Brake Caliper Replacement - Front
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level, no brake fluid needs to be
removed from the
reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level, remove brake fluid to the
midway point before proceeding.
4. Raise and support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel assembly.
6. Compress the brake caliper pistons.
^ Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
^ Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
^ Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end to prevent brake fluid
loss and contamination.
8. Remove the brake hose to caliper bolt from the brake caliper. 9. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
10. Remove the brake hose from the caliper.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8787
11. Remove the 2 brake caliper mounting bolts.
Caution: Do not depress the brake pedal with the brake rotors/calipers and/or the brake drums
removed. Damage to the brake system may result. If brake system damage occurs and is not
repaired, vehicle damage and/or personal injury or death may result
12. Remove the brake caliper from the brake caliper mounting bracket.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper to the brake caliper mounting bracket.
2. Install the 2 brake caliper mounting bolts.
Tighten the bolts to 108 Nm (80 ft. lbs.).
3. Remove the rubber cap or plug from the exposed brake hose fitting end.
Important: Install 2 New copper brake hose gaskets.
4. Assemble the 2 New copper brake hose gaskets and the brake hose to caliper bolt to the brake
hose.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8788
5. Install the brake hose to caliper bolt to the brake caliper.
Tighten the brake hose to caliper bolt to 40 Nm (30 ft. lbs.).
6. Bleed the hydraulic brake system. 7. Install the tire and wheel assembly. 8. Lower the vehicle. 9.
Fill the master cylinder reservoir to the proper level with clean brake fluid.
Rear
Brake Caliper Replacement - Rear
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level then no brake fluid needs to be
removed from
the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level then remove brake fluid to the
midway point before proceeding.
4. Raise and support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel assembly.
6. Compress the brake caliper pistons.
^ Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
^ Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
^ Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end to prevent brake fluid
loss and contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8789
8. Remove the brake hose to caliper bolt from the brake caliper. 9. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
10. Remove the caliper guide pin bolts. 11. Remove the brake caliper from the vehicle. 12. Inspect
the caliper assembly.
Installation Procedure
Important: Use denatured alcohol to clean the outside surface of caliper boots before installing new
brake pads.
1. If you are installing new brake pads use a C-clamp in order to compress the pistons to the
bottom of the caliper bores. Use the old brake pad, a
metal plate or a wooden block across the face of the pistons in order to protect the pistons and the
caliper boots.
Important: Use a small flat-bladed tool and lift the inner edge of the caliper boots next to both
pistons to release any trapped air.
2. Ensure that the caliper boots are below the level of the face of both pistons.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8790
3. Install the brake caliper to the brake caliper mounting bracket. 4. Perform the following
procedure before installing the caliper guide pin bolts.
4.1. Remove all traces of the original adhesive patch.
4.2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
4.3. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
5. Install the brake caliper mounting bolts.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the brake caliper guide pin bolts - rear 15 Series.
Tighten the to 42 Nm (31 ft. lbs.).
7. Remove the rubber cap or plug from the exposed brake hose fitting end.
Important: Install 2 New copper brake hose gaskets.
8. Assemble the 2 New copper brake hose gaskets and the brake hose to caliper bolt to the brake
hose.
9. Connect the brake hose at the caliper by installing the brake hose to caliper bolt.
Tighten the brake hose to caliper bolt to 40 Nm (30 ft. lbs.).
10. Bleed the hydraulic brake system. 11. Install the tire and wheel assembly. 12. Lower the
vehicle. 13. Fill the master cylinder reservoir to the proper level with clean brake fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8791
Brake Caliper: Service and Repair Disc Brake Hardware Replacement
Front
Disc Brake Hardware Replacement - Front
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
4. Remove the disc brake pads from the disc brake caliper mounting bracket. 5. Remove the disc
brake pad retainers from the disc brake caliper mounting bracket. 6. Inspect the disc brake
hardware.
7. Remove the caliper pin boots (4) from the disc brake caliper mounting bracket (3).
Installation Procedure
1. Lubricate the front brake caliper bushings, bolts and seals with high temperature silicone brake
lubricant.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8792
2. Install the caliper pin boots (4) to the disc brake caliper mounting bracket (3).
3. Install the disc brake pad retainers to the disc brake caliper mounting bracket. 4. Install the disc
brake pads to the disc brake caliper mounting bracket. 5. Install the disc brake caliper to the caliper
mounting bracket. 6. With the engine OFF, gradually apply the brake pedal approximately 2/3 of its
travel distance. 7. Slowly release the brake pedal. 8. Wait 15 seconds, then repeat steps 7-8 until a
firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Rear
Disc Brake Replacement - Rear
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting.
2. Remove the tire and wheel assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8793
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
3. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
4. Remove the disc brake pads from the disc brake caliper bracket. 5. Remove the disc brake pad
retainers from the disc brake caliper bracket.
6. Remove the caliper pins (5) from the disc brake caliper mounting bracket (3). 7. Remove the
caliper pin boots (4) from the disc brake caliper mounting bracket. 8. Inspect the disc brake
hardware.
Installation Procedure
1. Lubricate the brake caliper, bushings, bolts and seals with high temperature silicone brake
lubricant.
2. Install the caliper pin boots (4) to the disc brake caliper mounting bracket. 3. Install the caliper
pins (5) to the disc brake caliper mounting bracket (3). 4. Install the disc brake pad retainers to the
disc brake caliper bracket. 5. Install the disc brake pads to the disc brake caliper bracket. 6. Install
the disc brake caliper to the mounting bracket. 7. With the engine OFF, gradually apply the brake
pedal approximately 2/3 of its travel distance. 8. Slowly release the brake pedal. 9. Wait 15
seconds, then repeat steps 7-8 until a firm brake pedal is obtained. This will properly seat the brake
caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Specifications
Brake Pad: Specifications
Replace the disc brake pads when the friction surface (3) is worn to within 0.76 mm (0.030 inch) of
the mounting plates.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Service and Repair > Front
Brake Pad: Service and Repair Front
Brake Pads Replacement - Front
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level, no brake fluid needs to be
removed from the
reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level, remove brake fluid to the
midway point before proceeding.
4. Raise and support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel assembly.
6. Inspect the caliper operation.
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
7. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
8. Remove the brake pads from the caliper mounting bracket. 9. Remove and discard the anti-rattle
clips from the brake caliper mounting bracket.
10. Inspect the caliper and mounting bracket.
Installation Procedure
1. Install new anti-rattle clips to the inside ends of the caliper mounting bracket. 2. Install the brake
pads to the caliper mounting bracket.
^ Install the inner pad-1 wear indicator.
^ Install the outer pad-2 wear indicators.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Service and Repair > Front > Page 8799
3. Install the brake caliper. 4. Install the tire and wheel assembly. 5. Remove the safety stands. 6.
Lower the vehicle. 7. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of
its travel distance. 8. Slowly release the brake pedal. 9. Wait 15 seconds, then repeat steps 7-8
until a firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
10. Fill the master cylinder reservoir to the proper level with clean brake fluid. 11. Burnish the brake
pads and rotors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Service and Repair > Front > Page 8800
Brake Pad: Service and Repair Rear
Brake Pads Replacement - Rear
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level, no brake fluid needs to be
removed from the
reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level, remove brake fluid to the
midway point before proceeding.
4. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel
assembly. 6. Inspect the caliper operation.
7. Place a c-clamp as shown. Slowly bottom the pistons of the caliper. It may be necessary to
reposition the c-clamp to allow both of the pistons to
bottom into the caliper bores.
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
8. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
9. Inspect the caliper assembly.
10. Remove the brake pads from the brake caliper bracket. 11. Remove and discard the anti-rattle
clips from the brake caliper mounting bracket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Service and Repair > Front > Page 8801
1. Install the anti-rattle clips to the brake caliper bracket. 2. Install the brake pads to the brake
caliper bracket.
^ Install the inner pad-1 wear indicator.
^ Install the outer pad-2 wear indicators.
3. Install the brake caliper to the mounting bracket. 4. Install the tire and wheel assembly. 5. Lower
the vehicle. 6. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its
travel distance. 7. Slowly release the brake pedal. 8. Wait 15 seconds, then repeat steps 7-8 until a
firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads. 9. Fill the
master cylinder reservoir to the proper level with clean brake fluid.
10. Burnish the brakes pads and rotors as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Pad > Component Information >
Service and Repair > Front > Page 8802
Brake Pad: Service and Repair Burnishing Pads and Rotors
Burnishing Pads and Rotors
Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not
attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these
precautions could lead to Famous personal Injury and vehicle damage.
Burnishing the brake pads and brake rotors is necessary in order to ensure that the braking
surfaces are properly prepared after service has been performed on the disc brake system. This
procedure should be performed whenever the disc brake rotors have been refinished or replaced,
and/or whenever the disc brake pads have been replaced. 1. Select a smooth road with little or no
traffic. 2. Accelerate the vehicle to 48 km/h (30 mph).
Important: Use care to avoid overheating the brakes while performing this step.
3. Using moderate to firm pressure, apply the brakes to bring the vehicle to a stop. Do not allow the
brakes to lock. 4. Repeat steps 2 and 3 until approximately 20 stops have been completed. Allow
sufficient cooling periods between stops in order to properly
burnish the brake pads and rotors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures
Technical Service Bulletin # 00-05-22-002L Date: 090326
Brakes- Disc Brake Warranty Service And Procedures
INFORMATION
Bulletin No.: 00-05-22-002L
Date: March 26, 2009
Subject: Disc Brake Warranty Service and Procedures
Models: 1999-2010 GM Passenger Cars and Light Duty Trucks 2003-2010 HUMMER H2
2006-2010 HUMMER H3 1999-2004 Isuzu Light Duty Trucks (Canada Only) 2005-2009 Saab 9-7X
(Canada Only) 1999-2010 Saturn Vehicles (Canada Only)
EXCLUDING 2009-2010 Chevrolet Corvette ZR1
Supercede: This bulletin is being revised to inform you that due to improvements in vehicle brake
corner and wheel design, assembly plant build processes and dealership required tools like the
On-Car Lathe, measuring for Lateral Run Out (LRO) is no longer a required step when performing
base brake service. Due to this change, you are no longer required to enter the LRO measurement
on the repair order or in the warranty system failure code section. The bulletin information below
and the base brake labor operations have been updated accordingly. Due to this change it is more
important than ever to properly maintain your brake lathe (per the Brake Lathe Calibration
Procedure in this bulletin). Please discard Corporate Bulletin Number 00-05-22-002K (Section 05 Brakes).
For your convenience, this bulletin updates and centralizes all GM's Standard Brake Service
Procedures and Policy Guidelines for brake rotor and brake pad service and wear. For additional
information, the Service Technical College lists a complete index of available Brake courses. This
information can be accessed at www.gmtraining.com > resources > training materials > brakes
courseware index. In Canada, refer to Service Know How course 55040.00V and Hydraulic Brake
Certification program 15003.16H.
Important
PLEASE FAMILIARIZE YOURSELF WITH THESE UPDATES BEFORE PERFORMING YOUR
NEXT GM BRAKE SERVICE.
The following four (4) key steps are a summary of this bulletin and are REQUIRED in completing a
successful brake service.
1. Measure and Document Pre-Service Rotor Thickness* (REQUIRED on Repair Order) determine rotor clean-up/refinish/replace
2. Properly clean ALL brake corner mating surfaces - hub, rotor and wheel
3. Properly clean-up/refinish rotor, measure and document post-service rotor thickness
(REQUIRED on Repair Order)
Important If it is determined the rotor needs to be refinished, verify lathe equipment is properly
calibrated.
4. Properly reassemble the brake corner using proper torque tools, torque specification and torque
sequence - wheel lug nuts.
* The bulletin refers to Minimum Thickness specification as the minimum allowable thickness after
refinish. Always refer to SI to verify the spec stamped on the rotor is the minimum thickness spec
after refinish and not the discard spec.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8807
Bulletin Format
***REPAIR ORDER REQUIRED DOCUMENTATION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8808
Important
When using any one of the brake labor operations listed in this bulletin (except for H9709 - Brake
Burnish), the following two rotor measurements (1. Original Rotor Thickness, 2. Refinished Rotor
Thickness are required and MUST be written/documented on the repair order, or for your
convenience, complete the form (GM Brake Service Repair Order Documentation for Required
Measurements) shown above and attach it to the repair order. If the Warranty Parts Center
generates a request, this Documentation/Form must be attached to the repair order that is sent
back.
Important
Documentation of brake lathe maintenance and calibration as recommended by the lathe
manufacturer must be available for review upon request.
Repair Order Documentation - Rotor Original And Refinished Thickness - REQUIRED
When resurfacing a brake rotor or drum, the ORIGINAL thickness (measured thickness before
refinish) and REFINISHED thickness (measured thickness after refinish) MUST be
written/documented on the repair order hard copy for each rotor serviced. If a rotor replacement is
necessary, only the original thickness measurement needs to be recorded.
Repair Order Documentation - Explanation of Part Replacement - REQUIRED
If replacement of a brake component is necessary, proper documentation on the repair order is
required. See the following examples:
^ Brake rotor replacement - Customer comment was brake pulsation. Rotor was refinished on a
prior brake service. After rotor measurement, it was determined that refinishing the rotor again
would take it under the Minimum Thickness specification.
^ Brake pad replacement - Customer comment was brake squeak noise. On inspection, found pads
contaminated by fluid leak at caliper.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8809
TOOL INFORMATION
CORRECTION PLATE PART INFORMATION
Refer to TSB 01-05-23-001 for the Brake Align(R) application chart.
For vehicles repaired under warranty, Brake Align(R) Run-Out Correction Plates should be
submitted in the Net Amount at cost plus 40%. Brake Align(R) Run-Out Correction Plates are
available through the following suppliers:
- Dealer Equipment and Services
- Brake Align(R) LLC (U.S. Dealers Only)
* We believe this source and their products to be reliable. There may be additional manufacturers
of such products. General Motors does not endorse, indicate any preference for or assume any
responsibility for the products from this firm or for any such items, which may be available from
other sources.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8810
WARRANTY INFORMATION
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8811
WORKSHEET - BRAKE LATHE CALIBRATION
Important
Brake lathe calibration should be performed and recorded monthly or if you are consistently
measuring high LRO after rotor refinishing.
Disclaimer
GM Brake Service Procedure
GM BRAKE SERVICE PROCEDURE
1. Remove the wheel and caliper.
2. Measure rotor thickness. In order to determine if the rotor can be refinished, do the following
steps:
Important
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8812
If performing routine Brake Service for worn pads only, and the rotors are not damaged and
measure within specification - DO NOT REFINISH ROTORS.
1. Remove the rotor(s).
2. Measure the rotor for original thickness using a brake micrometer. Multiple measure points
should be taken and the lowest measurement
should be recorded.
3. Reference the Minimum Thickness specification stamped on the backside of the rotor or SI for
Minimum Thickness specification/other. In
most cases, the rotor should be refinished unless the measurement taken makes it obvious that
refinishing the rotor would take the measurement under the Minimum Thickness specification (then
replacement is necessary). DO NOT use any other manufacturers rotor specifications.
3. ***Record the lowest ORIGINAL rotor thickness measurement on the repair order hard copy as
noted in the "Repair Order Documentation - Rotor
Refinish" section of this bulletin.
4. Clean all of the mating surfaces between the hub, the rotor and the wheel using the J 42450A Wheel Hub Cleaning Kit and J 41013 - Whiz
Wheel(R).
If rotors are not to be refinished - Go To Step 8.
Important Cleaning all mating surfaces and making them free of corrosion, burrs and other debris
(which includes removal of Hubless rotors) is critical and MUST be performed whether using an
On-Car or Bench Lathe Refinish Procedure.
5. Be sure to follow the appropriate refinishing procedure listed below for the type of lathe you are
using.
Important Only replace the rotors if they do not meet the Minimum Thickness specification.
Important DO NOT REFINISH NEW ROTORS.
Important Only remove the necessary amount of material from each side of the rotor and note that
equal amounts of material do not have to be removed from both sides on any brake system using a
floating caliper.
Important Prior to making the cut, install the recommended clip-on style disc silencer supplied with
the lathe. Use of this silencer is critical to prevent chatter from occurring during the cut.
Bench Type Lathe
1. Refinish the existing rotor on an approved, well-maintained lathe to guarantee smooth, flat and
parallel surfaces.
2. Check for clean and true lathe adapters and make sure the arbor shoulder is clean and free of
debris or burrs. For more information, see the
"Brake Lathe Calibration Procedure (Bench-Type)" section in this bulletin.
3. On the outboard area of the rotor, position the cutting tools one eighth of an inch into the brake
pad area of the rotor. Feed the cutting tools
into the rotor until they cut the rotor to new metal, a full 360 degrees. Zero each dial and back off a
full turn
4. Move the cutting bits to the middle of the rotor and do the same procedure. If zero is passed
during the process, reset zero. Back off a full turn.
5. Position the cutting bits one eighth of an inch inside the inboard (closest to the hub) edge of the
brake pad contact area. Do the same
procedure. If zero is passed during the process, reset zero.
6. Back off a full turn and position the cutting bits all the way inboard in preparation to refinish the
full rotor surface. Advance both tool cutters to the
zero setting plus just enough to clean up the entire rotor surface.
7. After completing the refinish, sand both sides of the rotor for approximately one minute per side
using a sanding block and 130-150 grit sandpaper
to obtain a non-directional finish.
On-Car Type Lathe
1. Reinstall the rotor(s).
Important
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8813
When using the On-Car lathe on vehicles equipped with limited slip (or posi-trac) rear system, it is
critical that the rear drive shaft is disconnected/disengaged prior to operation of the On-Car lathe.
Remember to mark and re-index the drive shaft correctly on re-assembly to prevent creating
driveline vibration. Whenever the lathe drive motor is being switched on, the operator MUST keep
their body out of the wheel well area until the machine has reached its normal operating RPM.
2. Refinish the existing rotor on an approved, well-maintained lathe to guarantee smooth, flat and
parallel surfaces.
Important When raising the vehicle on the lift, be sure to have it at a good working height (waist
high is average) to accommodate mounting the On-Car lathe. Optimally, the center piston on the
lathe trolley will be mid-travel. If the lathe trolley center piston is completely compressed (bottoming
out) or inversely fully extended and hanging off the vehicle hub, this could affect the calibration time
of the lathe.
3. Select the correct adapter for the vehicle you're working on and mount it to the hub with the
vehicle lug nuts. Hand tighten 34-41 Nm (25-30 lb
ft) the nuts using equal torque. DO NOT use impact wrenches, excessive torque will damage the
adapter.
Important Ensure the adapter sits flush on the rotor hat surface. Be sure to remove any rust, rotor
retaining clips, etc. that may preclude the adapter from sitting flat on the mounting surface.
4. Connect the lathe to the adapter, turn on the lathe and activate the computer to compensate for
run-out in the hub.
5. Once the computer indicates the compensation process was successful, on the outboard area of
the rotor, position the cutting tools one eighth
of an inch into the brake pad area of the rotor. Feed the cutting tools into the rotor until they cut the
rotor to new metal, a full 360 degrees. Zero each dial and back off a full turn.
6. Move the cutting bits to the middle of the rotor and do the same procedure. If zero is passed
during the process, reset zero. Back off a full turn.
7. Position the cutting bits one eighth of an inch inside the inboard (closest to the hub) edge of the
brake pad contact area. Do the same
procedure. If zero is passed during the process, reset zero.
8. Back off a full turn and position the cutting bits all the way inboard in preparation to refinish the
full rotor surface. Advance both tool cutters
to the zero setting plus just enough to clean up the entire rotor surface.
9. After completing the refinish, sand both sides of the rotor for approximately one minute per side
using a sanding block and 130-150 grit
sandpaper to obtain a non-directional finish.
10. Dismount the lathe, but leave the lathe adapter attached to the vehicle.
6. Once the rotor has been properly machined, wash the rotor with soap and water (use a mild dish
washing soap) or wipe it clean with GM approved
brake cleaner, P/N 88862650 (Canadian P/N 88901247).
Important Thoroughly cleaning the rotor will prevent the possible transfer of finite metal dust left as
a by-product of machining to the pad material during the seating process, thus reducing the
opportunity for squeaks or other noises to occur.
7. ***Record the REFINISHED rotor thickness measurement on the repair order hard copy. Refer
to the "Repair Order Documentation - Rotor
Refinish" section of this bulletin.
8. Setting up to measure for Lateral Run Out (LRO):
Important Measuring for Lateral Run Out (LRO) (steps 8 - 15) is no longer required however, these
steps are being left in the overall procedure as a good check to be performed in the case of a
repeat pulsation complaint. If you are not checking for LRO, go to step 16.
Bench-Type Lathe
1. Ensure that the mating surfaces of the rotor hat section and the hub mating surface are clean
and free of debris.
2. Mount the new, original or refinished rotor onto the vehicle hub.
Important Always hold the rotor on the bottom half so any debris that may be dislodged from the
vents will fall out instead of falling into the mounting area. Any movement or jarring from the rotor
falling over on the studs can release rust from the vents on the rotor.
3. Tilt the top of the rotor in towards the vehicle so you can see the studs and ease the rotor onto
the studs.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8814
4. Slide the rotor all the way to the hub and hold it in place until you have placed one of the conical
washers (with the tapered hole side facing
out) and run the first lug nut up tight by hand so the rotor doesn't move when you release it.
5. Place the conical washers on the rest of the studs (with the tapered hole side facing out), start
and snug the lug nuts by hand.
6. Using the one half inch drive impact wrench and a torque stick (J 39544) or equivalent, start with
the lug nut opposite of the one you first
tightened by hand and tighten the lug nuts using a star pattern until they touch the hub but do not
completely torque. Then again, starting with the first lug nut you tightened by hand, tighten all the
lug nuts in a star pattern to the specific vehicle torque specification.
7. DO NOT reinstall the caliper or the wheel at this time.
On-Car Type Lathe
1. Leave the On-Car adapter on the wheel.
2. Proceed to Step 9.
9. Fasten the dial indicator to the steering knuckle so that the indicator needle contacts the rotor
outboard friction surface approximately 6.35 mm
(0.25 in) from the rotor's outer edge. The stylus should be perpendicular to the friction surface of
the rotor.
Important Make sure the dial indicator needle tip is screwed tight, a loose tip could cause false
readings.
10. Measure for LRO. Follow the procedure below to determine if the LRO is within specification
(0.050 mm (0.002 in) or LESS).
1. Rotate the rotor and locate the point on the rotor where the lowest dial indicator reading is
indicated and set the dial indicator to zero.
2. Rotate the rotor from the low point and locate the point with the highest dial indicator reading
(rotor "high spot"). Note the amount and mark
the location of the "high spot" on the rotor and mark the closest wheel stud relative to this location.
If the high point falls between two studs, mark both studs. In instances where the vehicle has
"capped lug nuts" you should mark the hub.
11. If the Lateral Run Out (LRO) measurement is 0.050 mm (0.002 in) or LESS, no correction is
necessary. Go to Step 15 if this is the first rotor
completed. Go to Step 16 if this is the second rotor completed. If the LRO is GREATER than 0.050
mm (0.002 in), go to Step 12.
12. If the LRO measurement is greater than 0.050 mm (0.002 in), use the following procedure to
correct for LRO:
Important If the LRO measurement is over 0.279 mm (0.011 in), determine the source or cause of
the LRO and correct it (i.e. verify drive axle nut torque specification, refinished rotor is source of
LRO due to a lathe qualification issue - see "Brake Lathe Calibration Procedure").
Hubless Rotor
1. Remove the rotor and using the Brake Align(R) application chart (found in TSB 01-05-23-001B),
choose the correct plate to bring the rotor
LRO to 0.050 mm (0.002 in) or less. The plates come in 0.0762 mm (0.003 in), 0.1524 mm (0.006
in) and 0.2286 (0.009 in) compensation. For more information on proper plate selection, see the
instruction video/DVD included in the "Brake Align(R)" kit or TSB 01-05-23-001B.
2. Align the V-notch of the selected Brake Align(R) correction plate to the marked wheel stud ("high
spot") or between the two points marked (if
the "high spot" is between two wheel studs).
Important IF Brake Align(R) Correction Plates are not available for the vehicle being serviced, refer
to SI Document - Brake Rotor Assembled Lateral Runout Correction for correcting LRO.
Important Per Brake Align(R) manufacturer, NEVER attempt to stack two or more Correction Plates
together on one hub. NEVER attempt to reuse a previously installed Correction Plate.
3. Reinstall the rotor using the same method and precautions as the first time - found in Step 8.
Make sure to index the rotor correctly to the
marks made in step 10, otherwise LRO will be comprised.
Hubbed / Captured / Trapped Rotor
1. Measure the rotor thickness.
2. Refinish or replace the rotor (see Service Information for further details).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8815
13. Use a Dial Indicator to measure the rotor to verify the LRO is within specification.
14. If using,
BENCH LATHE - DO NOT remove conical washers and lug nuts at this time.
ON-CAR LATHE - You must remove adapter and install conical washers and lug nuts to retain
rotor position.
Important For Hubless rotor design, while removing the adapter, you must hold the rotor tight to the
hub and install the top conical washer and lug nut first to ensure no debris falls between the
surface while removing the adapter. Then, install the remaining conical washers and lug nuts.
Otherwise, LRO will be comprised.
15. Perform Steps 1 through 7 on the opposite side of the vehicle (steps 1-12, if performing LRO).
16. Reinstall the rotors on both sides of the vehicle and perform the following steps:
1. Reinstall the calipers and pads.
2. Pump the brakes to pressurize the calipers.
3. Remove the lug nuts/conical washers.
4. Install and properly torque the wheels.
Important It is critical to follow the star pattern wheel torque procedure and use the proper tools
(torque stick or torque wrench) as referenced in SI.
17. Road test the vehicle to verify the repairs.
Brake Lathe Calibration Procedure
BRAKE LATHE CALIBRATION PROCEDURE
Calibration of the brake lathe should be performed and recorded monthly or whenever post-service
brake rotor LRO measurements are consistently reading above specification.
BENCH-TYPE LATHE
Use the following procedure to calibrate a Bench-type brake lathe:
1. After refinishing a rotor, loosen the arbor nut and while holding the inside bell clamp to keep it
from rotating, rotate the rotor 180 degrees.
2. Retighten the arbor nut and set the dial indicator on the rotor using the same instructions as
checking the run out on the vehicle.
3. Rotate the arbor and read the runout.
4. Divide the reading by two and this will give you the amount of runout the lathe is cutting into the
rotor.
Important If there is any runout, you will need to machine the inside bell clamp in place on the lathe
(this procedure is for a Bench type lathe ONLY, DO NOT machine inside the bell clamp on an
On-Car type lathe).
Machining the Inside Bell Clamp (Bench Type Lathe Only)
Any nicks or burrs on the shoulder of the arbor must be removed. An 80-grit stone can be used to
accomplish this. Spray WD-40(R) on the shoulder and with the lathe running, hold the stone flat
against the shoulder surface using slight pressure. When the burrs are gone, clean the surface.
Burrs must also be removed from the hub of the inside bell clamp. This can be accomplished with
the stone and WD-40(R). Keep the stone flat on the hub while removing the burrs. After removing
the burrs, clean the hub.
Place the bell clamp on the arbor of the lathe and use the small radius adapters first and then
spacers to allow you to tighten the arbor nut to secure the bell clamp to the lathe. Position the tool
bit in the left hand of the rotor truer so you can machine the face of the bell clamp. Machine the
face of the bell clamp taking just enough off of it to cut the full face of the clamp the full 360
degrees. Before you loosen the arbor nut, match mark the hub of the bell clamp to the arbor and
line up these marks before machining a rotor. A magic marker can be used to make the match
marks. Machine a rotor and recheck the calibration. Repeat this procedure on all Inside Bell
Clamps used.
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Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8816
Important
If runout is still present, contact the brake lathe supplier.
ON-CAR TYPE LATHE
Use the following procedure to calibrate an On-Car brake lathe:
1. Connect the lathe to a vehicle using the appropriate adapter.
2. Attach a vise-grip dial indicator to a fixed point in the wheel well and bring the dial indicator to a
flat surface on the cutting head.
3. Turn on the lathe and press the "start" button so the lathe begins to compensate.
4. Once compensation is complete, note the runout as measured by the dial indicator. Measured
runout at this point is overstated given that it is
outside the rotor diameter.
5. If runout is in excess of 0.1016 mm (0.004 in) (0.050 mm (0.002 in) as measured within the rotor
diameter), calibration must be tightened. Follow
manufacturer's instructions for tightening the calibration of the lathe. This information is found in the
manual supplied with the lathe.
Important If the machine is taking a long time to compensate during normal use, prior to checking
the lathe calibration, it is recommended that the machine be disconnected from the adapter and the
adapter (still connected to the vehicle) is rotated 180 degrees and the machine reattached. This will
accomplish two things: - It will re-verify the machine is properly attached to the adapter. - It will
change the location of the runout (phase) relative to the machine and thus possibly allow for quick
compensation as a result of the position change.
The following information has been added as a reference to ensure your Pro-Cut PFM lathe
provides a consistent smooth surface finish over long term usage.
Cutting Tips / Depth of Cut / Tip Life
The cutting tips must be right side up. Reference marks always face up. The cutting tips may not
have chips or dings in the surface of the points. Cuts of 0.1016-0.381 mm (0.004-0.015 in) will
provide the best surface finish and the optimal tip life. When cleaning or rotating the cutting bits,
make sure that the seat area for the tip on the tool is free and clear of debris.
Cutting Head
On each brake job, the technician must center the cutting head for that particular vehicle using one
of the mounting bolt holes on the slide plate. Once the head is centered, it is vital that the
technician use one hand to push the head firmly and squarely back into the dovetail on the slide
plate while using the other hand to tighten the Allen-Hex bolt that secures the head. Failure to do
this could result in chatter occurring during the cut.
Tool Holder Plate (Cutting Head)
The tool holder plate is the plate that the cutting arms are attached to. It can bend or break if a
technician accidently runs the cutting arms into the hub of the rotor while the rotor is turning. (Cuts
of more than 0.508 mm (0.020 in) can also bend this plate). Once bent, the lathe will most likely not
cut properly until the tool holder plate is replaced. In order to verify the condition of the tool holder
plate on a machine that will not cut right, remove the mounting bolt and remove the cutting head
from the slide plate. With the cutting head titled at an angle, lay the long edge of the tool holder
plate down on the flat part of the slide plate. If any gap can be seen between the edge and the slide
plate, the tool holder plate is bent and the source of vibration. Also check to ensure that the cutting
arms are lying flat on the upper side of the tool holder plate. If the mounting arm post is bent, it will
show itself by having the back of the cutting arm lifting off the surface of the tool holder.
Gib Adjustment / Loose Gib
As wear occurs between the slide plate and the box it rides on, you must take up the slack. You do
this by way of a moveable wedge, which we call the gib. Your lathe manual details adjustment
process, which you should perform when required after monthly checks or whenever surface finish
is inconsistent.
Brake Pulsation
BRAKE PULSATION
Brake pulsation is caused by brake rotor thickness variation. Brake rotor thickness variation causes
the piston in the brake caliper, when applied, to "pump" in and out of the caliper housing. The
"pumping" effect is transmitted hydraulically to the brake pedal. Brake pulsation concerns may
result from two basic conditions:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8817
1. Thickness Variation Pulsation is Caused by Lateral Run Out (LRO). LRO on a brake corner
assembly is virtually undetectable unless measured
(with a dial indicator after the brake service) and will not be detected as brake pulsation during an
after brake service test drive. If the brake corner is assembled with excessive LRO (greater than
0.050 mm (0.002 in), thickness variation will develop on the brake rotor over time and miles.
Excessive LRO will cause the brake pads to wear the brake rotors unevenly, which causes rotor
thickness variation. Pulsation that is the result of excessive Lateral Run Out usually develops in
4,800-16,000 km (3,000-10,000 mi). The more excessive the LRO, the faster the pulsation will
develop. LRO can also be induced when uneven torque is applied to wheel nuts (lug nuts).
Improper wheel tightening after tire rotation, spare tire usage, brake inspection, etc. can be the
cause of brake pulsation. Again, it usually takes 4,800-16,000 km (3,000-10,000 mi) AFTER the
service event for the condition to develop. The customer does not usually make the connection
between the service event and the awareness of the pulsation. The proper usage of torque
wrenches and/or torque sticks (torque limiting sockets) will greatly reduce or eliminate the pulsation
conditions after wheel service events. The improper use of impact wrenches on wheel nuts greatly
increases the likelihood of pulsation after wheel service.
The following are examples of pulsation conditions and reimbursement recommendations:
- If the customer noticed the condition between 4,800-16,000 km (3,000-10,000 mi) and it gradually
got worse, normally the repair would be covered. The customer may tolerate the condition until it
becomes very apparent.
- If a GM dealer performed a prior brake service, consider paying for the repair and then strongly
reinforce proper brake lathe maintenance.
- If the customer had the brake service done outside of a GM dealership, normally GM would not
offer any assistance.
- If a customer indicated they had wheel service, ask who performed the service. Then;
- If a GM dealer performed the service, consider paying for the repair and then strongly reinforce
the use of torque sticks at the dealer. Two common size torque sticks cover 90% of all GM
products. Each technician needs to use torque sticks properly every time the wheel nuts are
tightened.
- If the customer had the wheel service done outside of a GM dealership, normally GM would not
offer any assistance.
2. Thickness Variation Pulsation Caused by Brake Rotor Corrosion - Rotor corrosion is another
form of thickness variation, which can cause a
pulsation concern and can be addressed as follows:
- Cosmetic Corrosion:
In most instances rotor corrosion is cosmetic and refinishing the rotor is unnecessary.
- Corrosion - Pulsation Caused by Thickness Variation (Lot Rot / Low Miles - 0-321 km (0-200 mi):
At times more extensive corrosion can cause pulsation due to thickness variation. This usually
happens when the vehicle is parked for long periods of time in humid type conditions and the
braking surface area under the pads corrodes at a different rate compared to the rest of the braking
surface area. Cleaning up of braking surfaces (burnishing) can be accomplished by 10 - 15
moderate stops from 56- 64 km/h (35 - 40 mph) with cooling time between stops. If multiple
moderate braking stops do not correct this condition, follow the "Brake Rotor Clean-Up Procedure"
below.
- Corrosion - Pulsation Caused by Thickness Variation (without rotor flaking / higher mileage 3,200-8,000 km (2,000-5,000 mi):
In some cases, more extensive corrosion that is not cleaned up by the brake pad over time and
miles can cause the same type of pulsation complaint due to thickness variation. In these cases,
the rotor surface is usually darker instead of shiny and a brake pad foot print can be seen against
the darker surface. This darker surface is usually due to build-up, on the rotor material surface,
caused by a combination of corrosion, pad material and heat. To correct this condition, follow the
"Brake Rotor Clean-up Procedure" below.
- Corrosion - Pulsation Caused by Thickness Variation (with rotor flaking / higher mileage - 8,000 +
km (5,000 + miles) :
At times, more extensive corrosion over time and miles can cause pulsation due to thickness
variation (flaking). This flaking is usually a build up, mostly on the rotor material surface, caused by
a combination of corrosion, pad material and heat. When rotor measurements are taken, the low
areas are usually close to the original rotor thickness (new rotor) measurement and the high areas
usually measure more than the original rotor thickness (new rotor) measurement (depending on
mileage and normal wear). To correct this condition, follow the "Brake Rotor Clean-up Procedure"
described below.
Important In some flaking instances, cleaning-up this type of corrosion may require more rotor
material to be removed then desired. Customer consideration should be taken in these situations
and handled on a case by case basis, depending on the amount/percentage of rotor life remaining
and the vehicle's warranty time and miles.
Brake Rotor Clean-Up Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8818
BRAKE ROTOR CLEAN-UP PROCEDURE
Clean-up the rotors on an approved, well-maintained brake lathe to guarantee smooth, flat and
parallel surfaces. Check for clean and true lathe adapters and make sure the arbor shoulder is
clean and free of debris or burrs. For more information see the "Brake Lathe Calibration Procedure"
section in this bulletin.
1. On the outboard area of the rotor, position the cutting tools one eighth of an inch into the brake
pad area of the rotor. Feed the cutting tools into the
rotor until they cut the rotor to new metal, a full 360 degrees. Zero each dial and back off a full turn.
2. Move the cutting bits to the middle of the rotor and do the same procedure. If zero is passed
during the process, reset zero. Back off a full turn.
3. Position the cutting bits one eighth of an inch inside the inboard (closest to the hub) edge of the
brake pad contact area. Do the same procedure. If
zero is passed during the process, reset zero.
4. Back off a full turn and position the cutting bits all the way inboard in preparation to refinish the
full rotor surface. Advance both tool cutters to the
zero setting plus just enough to clean up the entire rotor surface.
5. After completing the refinish, sand both sides of the rotor for approximately one minute per side
using a sanding block and 130-150 grit sandpaper
to obtain a non-directional finish.
Important Only remove the necessary amount of material from each side of the rotor and note that
equal amounts of material do not have to be removed from both sides on any brake system using a
floating caliper.
Important In many of these instances, such a minimal amount of material is removed from the rotor
that customer satisfaction is not a concern for future brake services. This procedure is intended to
"Clean-up" the rotor surface and should be conveyed to the customer as such - not as "cut",
"refinish" or "machine", which tends to be terms understood as a substantial reduction of rotor
material/life. If the brake lathe equipment being used is not capable of removing minor amounts of
material while holding tolerances, further lathe maintenance, repair, updates or equipment
replacement may be necessary.
Brake Noise
BRAKE NOISE
Some brake noise is normal and differences in loading, type of driving, or driving style can make a
difference in brake wear on the same make and model. Depending on weather conditions, driving
patterns and the local environment, brake noise may become more or less apparent. Verify all
metal-to-metal contact areas between pads, pad guides, caliper and knuckles are clean and
lubricated with a thin layer of high temperature silicone grease. Brake noise is caused by a
"slip-stick" vibration of brake components. While intermittent brake noise may be normal,
performing 3 to 4 aggressive stops may temporarily reduce or eliminate most brake squeal. If the
noise persists and is consistently occurring, a brake dampening compound may be applied to the
back of each pad. This allows parts to slide freely and not vibrate when moving relative to each
other. Use Silicone Brake Lubricant, ACDelco P/N 88862181 (Canadian P/N 88862496) or
equivalent.
The following noises are characteristics of all braking systems and are unavoidable. They may not
indicate improper operation of the brake system.
Squeak/Squeal Noise:
- Occurs with front semi-metallic brake pads at medium speeds when light to medium pressure is
applied to the brake pedal.
- Occasionally a noise may occur on rear brakes during the first few stops or with cold brakes
and/or high humidity.
Grinding Noise:
- Common to rear brakes and some front disc brakes during initial stops after the vehicle has been
parked overnight.
- Caused by corrosion on the metal surfaces during vehicle non-use. Usually disappears after a few
stops.
Groan Noise:
A groan type noise may be heard when stopping quickly or moving forward slowly from a complete
stop. This is normal. On vehicles equipped with ABS, a groan or moan type noise during hard
braking applications or loose gravel, wet or icy road conditions is a normal function of the ABS
activation.
Key Points - Frequently Asked Questions
KEY POINTS - FREQUENTLY ASKED QUESTIONS
- Q: How do on-car lathes react to Axle Float? Does the play affect the machining of the rotor,
either surface finish or LRO?
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8819
A: Because the Pro-Cut on-car lathe adjusts in a live mode while spinning the hub/rotor, the
dynamics of a floating axle are effectively eliminated. Once the lathe is compensated, there is no
difference in the cutting/surface finish and LRO are just the same as with a non-floating axle.
- Q: Which lathe is essential for performing brake work, the bench or on-car?
A: Dealers must have a well maintained bench lathe and well maintained on-car lathe. These
lathes need to be calibrated on a monthly basis. BOTH lathes are essential to providing quality
brake service.
- Q: What is the expected tip life for an on-car lathe?
A: The geometry and composition of the Pro-Cut tips are designed for "single pass" cutting. When
using the Pro-Cut the cutting depth should be set to take all material needed to get below rust
grooves, eliminate all run-out and resurface the entire disc in a single pass. Cuts of 0.1016-0.381
mm (0.004-0.015 in) will provide the best surface finish and the optimal tip life. No "skim cut" or
"finish cut" is needed. Failure to follow this procedure will shorten tip life. The Pro-cut tips will last
between 7-12 cuts per corner. With three usable corners, a pair of tips is good for at least 21 cuts.
- Q: Why does GM recommend the use of single pass (referred to as "positive rake") bench and
on-car brake lathes?
A: GM Service and GM Brake Engineering have performed competitive evaluations on a significant
number of bench and on-car brake lathes. These tests measured critical performance
characteristics such as flatness, surface finish and the ability of the lathe to repeat accuracy over
many uses. In each test, single pass lathe designs out performed the competitors. Single pass
brake lathes are more productive requiring less time to perform the same procedure.
- Q: Is it okay to leave the caliper/pads installed while cutting rotors using an on-car lathe?
A: On-car lathes should never be used with the pads and calipers installed on the vehicle. The
debris from cutting the rotors can contaminate the brake pads/calipers which can lead to other
brake concerns and comebacks.
- Q: What information needs to be documented on the Repair Order?
A: Any claim that is submitted using the labor operations in this bulletin, must have the Original
Rotor Thickness and Refinish Rotor Thickness (if refinished) documented on the repair order. For
more information, refer to the "Repair Order Required Documentation" section of this bulletin.
All Warranty Repair Orders paid by GM, are subject to review for compliance and may be debited
where the repair does not comply with this procedure.
Brake Warranty
BRAKE WARRANTY
Brake Rotors:
- Brake rotor warranty is covered under the terms of the GM New Vehicle Limited Warranty.
Reference the vehicle's warranty guide for verification.
- Rotors should not be refinished or replaced during normal/routine pad replacement.
- Rotors should not be refinished or replaced and is ineffective in correcting brake squeal type
noises and/or premature lining wear out.
- Rotors should not be refinished or replaced for cosmetic corrosion. Clean up of braking surfaces
can be accomplished by 10-15 moderate stops from 56-64 km/h (35-40 mph) with cooling time
between stops.
- Rotors should not be refinished or replaced for rotor discoloration/hard spots.
- Rotors should be refinished NOT replaced for Customer Pulsation concerns. This condition is a
result of rotor thickness variation, usually caused by LRO (wear induced over time and miles) or
corrosion (Lot Rot).
- When rotor refinishing, only remove the necessary amount of material from each side of the rotor
and note that equal amounts of material do not have to be removed from both sides on any brake
system using a floating caliper.
- Rotors should be refinished for severe scoring - depth in excess of 1.5 mm (0.060 in).
Important If the scoring depth is more than 1.5 mm (0.060 in) after the rotor is refinished, it should
be replaced.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Brakes- Disc Brake Warranty Service And Procedures > Page 8820
- It is not necessary to replace rotors in pairs. Rotors may be replaced individually. However,
caution should be exercised, as a variance in surface finish may cause a brake pull condition.
- New rotors should not be refinished before installation. Original equipment rotor surfaces are
ground to ensure smooth finish and parallelism between mounting and friction surfaces. If a new
rotor has more than 0.050 mm (0.002 in) Lateral Run Out (LRO) when properly mounted on the
hub, correct it using one of the following methods:
1. For hubless rotor designs, use the correction plate procedure found in the "GM Brake Service
Procedure for Hubless Rotors" outlined in this
bulletin.
2. For hubbed/trapped/captured rotor designs, refinish the rotor using an On-Car lathe and the
procedure outlined in this bulletin.
- Never reuse rotors that measure under the Minimum Thickness specification. In this instance, the
rotor should be replaced.
Important If the Minimum Thickness specification is not visible on the rotor, reference Service
Information (SI) for the specific vehicle application. DO NOT use any other manufacturers rotor
specifications.
Brake Pads:
Important When determining the warranty coverage (as an example) - if all four front or four rear
brake pads are excessively worn evenly, that would NOT be covered under warranty since this
type of wear is most likely due to driving habits or trailering. However, if the brake pads are
excessively worn un-evenly, side-to-side or same side/inner-to-outer pads, then consideration
should be given to cover this under warranty since this type of wear is most likely due to poor
operation of other braking components.
- Consideration should be given for covering brake pads up to 39,000 km (24,000 mi) (excluding
owner abuse, excessive trailering, or the situations that would not be considered normal use).
- Installation of new rotors does not require pad replacement. Do not replace pads unless their
condition requires it - excessively worn, damage or contaminated.
Brake Wear:
Several factors impact brake lining wear and should be taken into account when reviewing related
issues:
- heavy loads / high temperatures / towing / mountainous driving / city driving / aggressive driving /
driver braking characteristics (left foot or two feet)
The following are conditions that may extend brake lining wear:
- light loads / highway driving / conservative driving / level terrain
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Technical Service Bulletins > Page 8821
Brake Rotor/Disc: Specifications
Front Brakes JC5/JH5 All
Rotor Discard Thickness *
.............................................................................................................................................................
27.50 mm (1.082 inch) Rotor Minimum Allowable Thickness After Refinish
....................................................................................................................... 28 0 mm (1.10 inch)
Rotor Thickness-new ...........................................................................................................................
.............................................. 29.0 mm (1.14 inch) Rotor Maximum Allowable Lateral Runout
.................................................................................................................................... 0.13 mm
(0.005 inch) Rotor Maximum Allowable Scoring
................................................................................................................................................ 1.50
mm (0.139 inch) Rotor Maximum Allowable Thickness Variation
.......................................................................................................................... 0.025 mm (0.001
inch)
Front Brakes JH6
Rotor Discard Thickness *
.............................................................................................................................................................
36.50 mm (1.437 inch) Rotor Minimum Allowable Thickness After Refinish
....................................................................................................................... 37.0 mm (1.46 inch)
Rotor Thickness-new ...........................................................................................................................
.............................................. 38.0 mm (1.50 inch) Rotor Maximum Allowable Lateral Runout
.................................................................................................................................... 0.13 mm
(0.005 inch) Rotor Maximum Allowable Scoring
................................................................................................................................................ 1.50
mm (0.139 inch) Rotor Maximum Allowable Thickness Variation
.......................................................................................................................... 0.025 mm (0.001
inch)
Rear Brakes JC5/JH5 Utility Only
Rotor Discard Thickness*
..............................................................................................................................................................
28.50 mm (1.122 inch) Rotor Minimum Allowable Thickness After Refinish
..................................................................................................................... 29.0 mm (1.142 inch)
Rotor Thickness-new ...........................................................................................................................
............................................ 30.0 mm (1.181 inch) Rotor Maximum Allowable Lateral Runout
.................................................................................................................................... 0.13 mm
(0.005 inch) Rotor Maximum Allowable Scoring
................................................................................................................................................ 1.50
mm (0.139 inch) Rotor Maximum Allowable Thickness Variation
.......................................................................................................................... 0.025 mm (0.001
inch)
Rear Brakes JH6
Rotor Discard Thickness *
.............................................................................................................................................................
27.50 mm (1.082 inch) Rotor Minimum Allowable Thickness After Refinish
..................................................................................................................... 28.0 mm (1.102 inch)
Rotor Thickness-new ...........................................................................................................................
............................................ 29.0 mm (1.141 inch) Rotor Maximum Allowable Lateral Runout
.................................................................................................................................... 0.13 mm
(0.005 inch) Rotor Maximum Allowable Scoring
................................................................................................................................................ 1.50
mm (0.139 inch) Rotor Maximum Allowable Thickness Variation
.......................................................................................................................... 0.025 mm (0.001
inch)
* All brake rotors have a discard dimension cast into them Replace any rotor that does not meet
this specification After refinishing the rotor, replace any rotor that does not meet the minimum or
discard thickness specifications.
Backing Plate Bolts ..............................................................................................................................
................................................ 135 Nm (100 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement
Brake Rotor/Disc: Service and Repair Brake Rotor Replacement
Front
Brake Rotor Replacement - Front
Tools Required ^
J41013 Rotor Resurfacing Kit
^ J42450-A Wheel Hub Resurfacing Kit
Removal Procedure
Notice: Any new rotor must have the protective coating removed from the friction surfaces before
being placed in service. Use Goodwrench Brake Parts Cleaner, GM P/N 123777981 (Canadian
P/N 10953463), or the equivalent, and wipe the surface clean with clean cloths. Do not use
gasoline, kerosene, or other oil base solvents which may leave an oily residue. This residue is
damaging to the brake lining and is flammable.
1. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel
assembly. 3. Mark the relationship of the rotor to the hub.
4. Remove the 2 brake caliper bracket mounting bolts.
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and brake caliper mounting bracket as an assembly and support with
heavy mechanic's wire or equivalent. DO NOT
disconnect the hydraulic brake flexible hose from the caliper.
6. Remove the rotor retaining push nuts from the wheel studs, if applicable. 7. It may be necessary
to strike the end of the hub or the rotor with a deadblow hammer to separate the rotor from the hub.
8. Remove the rotor.
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Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8824
9. If the rotor is difficult to remove due to corrosion in the hub area use the following procedure to
remove the rotor; 25 series only.
^ Clean all the surface areas and the threaded holes of contamination.
^ Generously apply penetrating oil or the equivalent to the hub/rotor area.
^ Insert (2) M10 x 1.5 bolts (jack screws) into the threaded holes of the rotor.
^ Tighten both bolts evenly to force the rotor from the hub.
Installation Procedure
Notice: Whenever the brake rotor has been separated from the wheel bearing flange, clean any
rust or foreign material from the mating surface of the rotor and flange with the J42450 hub
cleaning kit. Failure to do this may result in increased lateral runout of the rotor and brake
pulsation.
1. Use the J42450-A to clean all rust and contaminants from the mating surface of the hub flange.
2. Use the J41013 to clean all rust and contaminants from the inside diameter of the hub section of
the brake rotor to prevent any foreign material
from getting between the brake rotor and the hub flange.
Important: If the rotor was removed using the jack screw method you must ensure that the hub
flange is free of nicks or marks caused by this procedure. Remove all raised nicks or marks before
installing the rotor.
3. Align the rotor to its original position on the hub, if applicable, and install the rotor. 4. Install the
caliper and caliper mounting bracket assembly. 5. Perform the following procedure before installing
the brake caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
Notice: Refer to Fastener Notice in Service Precautions.
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Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8825
6. Install the 2 caliper bracket mounting bolts.
^ Tighten the brake caliper bracket mounting bolts to 175 Nm (121 ft. lbs.), 15 Series.
^ Tighten the brake caliper bracket mounting bolts to 300 Nm (221 ft. lbs.), 25 Series.
7. Install the tire and wheel assembly. 8. Lower the vehicle. 9. With the engine OFF, gradually
apply the brake pedal to approximately 2/3 of its travel distance.
10. Slowly release the brake pedal. 11. Wait 15 seconds, then repeat steps 9-10 until a firm pedal
is obtained. This will properly seat the brake caliper pistons and brake pads. 12. Fill the master
cylinder reservoir to the proper level with clean brake fluid.
Rear
Brake Rotor Replacement - Rear
Removal Procedure
Tools Required ^
J41013 Rotor Resurfacing Kit
^ J42450-A Wheel Hub Resurfacing Kit
1. Release the park brake. 2. Raise and suitably support the vehicle. Refer to Vehicle Lifting. 3.
Remove the tire and wheel assembly.
4. Mark the relationship of the rotor to the hub. 5. Remove the brake caliper bracket mounting bolts.
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
6. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy
mechanic's wire or equivalent. DO NOT disconnect the
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Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8826
hydraulic brake flexible hose from the caliper.
7. Remove the rotor retaining push nuts from the wheel studs, if applicable. 8. It may be necessary
to strike the end of the hub or the rotor with a deadblow hammer to separate the rotor from the hub.
9. Remove the rotor by slowly fuming the rotor while pulling the rotor away from the axle.
Installation Procedure
Notice: Whenever the brake rotor has been separated from the wheel bearing flange, clean any
rust or foreign material from the mating surface of the rotor and flange with the J42450 hub
cleaning kit. Failure to do this may result in increased lateral runout of the rotor and brake
pulsation.
1. Use the J42450-A to clean all rust and contaminants from the mating surface of the hub flange.
2. Use the J41013 to clean all rust and contaminants from the inside diameter of the hub section of
the brake rotor to prevent any foreign material
from getting between the brake rotor and the hub flange.
3. Install the rotor by slowly fuming the rotor while pushing the rotor towards the axle. 4. Install the
caliper and the bracket as an assembly to the vehicle. 5. Perform the following procedure before
installing the caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
Notice: Refer to Fastener Notice in Service Precautions.
6. Install the caliper bracket mounting bolts.
^ For the 15 Series, tighten the brake caliper bracket mounting bolts to 175 Nm (129 ft. lbs.).
^ For the 25 series, tighten the brake caliper bracket mounting bolts to 300 Nm (221 ft. lbs.).
7. Install the tire and wheel assembly. 8. Lower the vehicle. 9. With the engine OFF, gradually
apply the brake pedal to approximately 2/3 of its travel distance.
10. Slowly release the brake pedal. 11. Wait 15 seconds, then repeat steps 9-10 until a firm pedal
is obtained. This will properly seat the brake caliper pistons and brake pads. 12. Fill the master
cylinder reservoir to the proper level with clean brake fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8827
Brake Rotor/Disc: Service and Repair Disc Brake Splash Shield Replacement
Front
Disc Brake Splash Shield Replacement - Front
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Remove the hub and bearing assembly.
4. Remove the splash shield, for 15 series.
5. Remove the splash shield, for 25 series.
Installation Procedure
1. Install the splash shield, for 15 series.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8828
2. Install the splash shield, for 25 series. 3. Install the hub and bearing assembly. 4. Install the tire
and wheel assembly. 5. Remove the safety stands. 6. Lower the vehicle.
Rear
Disc Brake Backing Plate Replacement - Rear
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting. 3. Remove
the tire and wheel assembly. 4. Relieve the tension from the park brake cables by loosening the nut
at the equalizer. 5. Remove the rear park brake cable from the park brake actuator lever. 6.
Remove the park brake cable from the mounting bracket by depressing the locking tabs. 7.
Remove the rotor. 8. Remove the axle shaft. 9. Remove the park brake shoe.
10. Remove the backing plate nuts. 11. Remove the backing plate from axle housing flange.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8829
1. Install the backing plate to the axle housing flange.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the backing plate nuts.
Tighten the backing plate bolts to 135 Nm (100 ft. lbs.).
3. Install the park brake shoe. 4. Install the axle shaft. 5. Adjust the park brake shoe. 6. Install the
rotor. 7. Install the park brake cable to the mounting bracket until the locking tabs snap into place.
8. Install the rear park brake cable to the park brake actuator lever. 9. Tighten the nut to the
intermediate cable at the equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
10. Install the tire and wheel assembly. 11. Remove the safety stands. 12. Lower vehicle. 13.
Adjust park brake cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8830
Brake Rotor/Disc: Service and Repair Burnishing Pads and Rotors
Burnishing Pads and Rotors
Caution: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not
attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these
precautions could lead to Famous personal Injury and vehicle damage.
Burnishing the brake pads and brake rotors is necessary in order to ensure that the braking
surfaces are properly prepared after service has been performed on the disc brake system. This
procedure should be performed whenever the disc brake rotors have been refinished or replaced,
and/or whenever the disc brake pads have been replaced. 1. Select a smooth road with little or no
traffic. 2. Accelerate the vehicle to 48 km/h (30 mph).
Important: Use care to avoid overheating the brakes while performing this step.
3. Using moderate to firm pressure, apply the brakes to bring the vehicle to a stop. Do not allow the
brakes to lock. 4. Repeat steps 2 and 3 until approximately 20 stops have been completed. Allow
sufficient cooling periods between stops in order to properly
burnish the brake pads and rotors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Disc Brake System > Brake Rotor/Disc > Component
Information > Service and Repair > Brake Rotor Replacement > Page 8831
Brake Rotor/Disc: Service and Repair Brake Rotor Refinishing
Brake Rotor Refinishing
Tools Required ^
J41013 Rotor Resurfacing Kit
^ J42450-A Wheel Hub Resurfacing Kit
1. The disc brake rotors do not require refinishing as part of routine brake system service. Do not
refinish disc brake rotors in an attempt to correct
the following conditions: ^
Brake system noise - squeal, growl, groan
^ Uneven and/or premature disc brake pad wear
^ Superficial or cosmetic corrosion/rust of the disc brake rotor surface
^ Scoring of the disc brake rotor surface less than the maximum allowable specification
2. Disc brake rotors should only be refinished if the following conditions exist:
^ Excessive corrosion/rust and/or pitting
^ Cracks and/or heat spots
^ Excessive blueing discoloration
^ Scoring of the disc brake rotor surface in excess of the maximum allowable specification
^ Lateral runout in excess of the maximum allowable specification
3. Inspect each of the disc brake rotors and determine if the rotors can be refinished and remain
above the minimum allowable thickness after refinish
specification: 3.1.
Inspect the thickness of each of the disc brake rotors.
3.2. Inspect each of the disc brake rotors for excessive surface wear and/or lateral runout.
4. If the rotors can be refinished, proceed with the rotor refinishing procedure.
Important: Failure to clean the corrosion from the wheel bearing flange, brake rotor mating surface,
and brake rotor mounting face may result in increased lateral runout of the brake rotor and brake
system pulsation.
5. Use the J41013 in order to thoroughly clean any corrosion from the wheel bearing flange. 6. Use
the J42450-A in order to thoroughly clean any corrosion/rust from the brake rotor mating surface
and mounting face. 7. Mount the brake rotor to the brake lathe according to the lathe
manufacturer's instructions, ensuring that all mounting attachments and adapters are
clean and free of debris.
8. Ensure that any vibration dampening attachments are securely in place. 9. With the brake lathe
running, slowly bring in the cutting tools until they just contact the brake rotor friction surfaces.
10. Observe the witness mark on the brake rotor. If the witness mark extends approximately
three-quarters or more of the way around the brake rotor
surface on each side, the brake rotor is properly mounted to the lathe.
11. If the witness mark does not extend three-quarters or more of the way around the brake rotor,
re-mount the rotor to the lathe. 12. Following the brake lathe manufacturer's instructions, refinish
the brake rotor. 13. After each successive cut, inspect the brake rotor thickness. 14. If at any time
the brake rotor exceeds the minimum allowable thickness after refinish specification, the brake
rotor must be replaced. 15. After refinishing the brake rotor, use the following procedure in order to
obtain the desired non-directional finish:
15.1. Follow the brake lathe manufacturer's recommended speed setting for applying a
non-directional finish
15.2. Using moderate pressure, apply the non-directional finish: ^
If the lathe is equipped with a non-directional finishing tool, apply the finish with 120 grit aluminum
oxide sandpaper
^ If the lathe is not equipped with a non-directional finishing tool, apply the finish with a sanding
block and 150 grit aluminum oxide sandpaper
15.3. After applying a non-directional finish, clean each friction surface of the brake rotor with
denatured alcohol or an equivalent brake cleaner
16. Remove the brake rotor from the brake lathe.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Drum Brake System > Wheel Cylinder > Component
Information > Technical Service Bulletins > Brakes - Wheel Cylinder Inspection Guidelines
Wheel Cylinder: Technical Service Bulletins Brakes - Wheel Cylinder Inspection Guidelines
Bulletin No.: 03-05-24-001A
Date: March 21, 2005
INFORMATION
Subject: Service Information Regarding Rear Brake Drum Wheel Cylinder Inspections
Models: 2005 and Prior GM Passenger Cars and Trucks 2005 and Prior Saturn Vehicles
with Rear Drum Brakes
Supercede:
This bulletin is being revised add model years and include all GM vehicles. Please discard
Corporate Bulletin Number 03-05-24-001 (Section 03 - Suspension).
This bulletin provides information on proper inspection of rear drum brake wheel cylinders.
Important:
It is not recommended that dust boots be removed during inspection processes as dirt and debris
could contaminate the wheel cylinder bore causing premature wear of the wheel cylinder. In
addition, most bores should look damp and some lubricant may drip out from under the boot as a
result of lubricant being present.
All rear drum brake wheel cylinders are assembled with a lubricant to aid in assembly, provide an
anti-corrosion coating to the cylinder bore, and lubricate internal rubber components. As a result of
this lubrication process, it is not uncommon for some amount of lubricant to accumulate at the ends
of the cylinder under the dust boot.
Over time, the lubricant may work its way to the outside of the boot and cause an area of the boot
to look damp. Evidence of a damp area on the boot does not indicate a leak in the cylinder.
However, if there is excessive wetness (i.e. drips) coming from the boot area of the wheel cylinder,
it could indicate a brake hydraulic fluid leak requiring wheel cylinder replacement. (Refer to the
Wheel Cylinder Replacement procedures in the appropriate Service Manual.)
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure
Brake Bleeding: Service and Repair ABS Automated Bleed Procedure
W/JL4
ABS Automated Bleed Procedure (W/JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure is ONLY to be performed on vehicles equipped with option code JL4,
Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this bleeding
procedure. If you have not yet performed the base hydraulic brake system bleeding procedure,
refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool. 2. Apply the park brake fully. 3. Start the engine and allow the engine to idle.
4. Depress the brake pedal firmly and maintain steady pressure on the pedal. 5. From the VSES
Special Functions menu on the scan tool, select the Automated Bleed procedure. 6. Send the
automated bleed command by pressing the On key on the scan tool.
After initiating the automated bleed procedure, the brake pedal will drop and then pulse back up, 8
times, while the LPA is being purged of any trapped air.
7. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT 3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half full during this bleeding procedure and add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm, when cap removal is necessary.
8. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 9.
Install a transparent hose over the end of the bleeder valve.
10. Submerge the open end of the transparent hose into a transparent container partially filled with
Delco Supreme II, GM P/N 12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
11. Have an assistant slowly depress the brake pedal and maintain pressure on the pedal. 12.
Loosen the bleeder valve to purge air from the wheel hydraulic circuit. 13. Tighten the bleeder
valve when full brake pedal travel has occurred. 14. Have the assistant slowly release the brake
pedal. Wait 5 seconds before proceeding to the next step. 15. Repeat steps 11-14 until all air is
purged from the same wheel hydraulic circuit. 16. After all air has been purged from the right rear
hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end wrench onto
the LEFT REAR wheel hydraulic circuit bleeder valve.
17. Repeat steps 9-15 at the left rear wheel hydraulic circuit. 18. After all air has been purged from
the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper box-end
wrench onto
the RIGHT FRONT wheel hydraulic circuit bleeder valve.
19. Repeat steps 9-15 at the right front wheel hydraulic circuit. 20. After all air has been purged
from the right rear hydraulic circuit and the bleeder valve is tightened securely, install a proper
box-end wrench onto
the LEFT FRONT wheel hydraulic circuit bleeder valve.
21. Repeat steps 9-15 at the left front wheel hydraulic circuit. 22. Fill the brake master cylinder
reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
23. Install a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
24. Install a transparent hose over the end of the bleeder valve. 25. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
26. Use the procedure below to purge the Medium Pressure Accumulator (MPA) of any trapped air.
26.1. With the engine still idling, select the Bleed MPA procedure from the VSES Special Functions
menu.
26.2. Send the bleed MPA command by pressing the On key on the scan tool.
26.3. Open the LEFT FRONT wheel hydraulic circuit bleeder valve.
Important: Ensure that you fully release the brake pedal for at least 2 seconds between pedal
strokes. The amount of accumulated time between pedal strokes is calculated to deliver the most
thorough bleed of the Medium Pressure Accumulator (MPA).
26.4. Depress the brake pedal as far as possible using a smooth stroke.
26.5. Release the brake pedal using a smooth stroke.
26.6. Repeat steps 26.4-26.5 until 13 complete pedal strokes have been performed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure > Page 8842
Important: Observe the MPA switch parameter as the pedal strokes are being performed. The MPA
switch parameter should change from Uncharged to Charged several times during the first 8 or 9
strokes. After approximately 10 pedal strokes, the MPA switch parameter should remain Charged.
If the parameter does not change, repeat all of step 26.
26.7. The valves within the BPMV are active for the first 13 complete pedal strokes to enable the
MPA to be filled and discharged, forcing any trapped air out of the LEFT FRONT wheel hydraulic
circuit bleeder valve.
26.8. Continue to depress and release the brake pedal while observing the fluid within the
transparent hose. When no air is observed exiting the hydraulic system, proceed to the next step.
26.9. Depress the brake pedal and maintain pedal position.
26.10. Have an assistant tighten the bleeder valve.
26.11. Release the brake pedal.
27. Remove the scan tool from the vehicle. 28. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT 3 brake fluid from a clean, sealed brake fluid container.
29. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 30. If the
brake pedal feels spongy, repeat this entire bleed procedure. If the brake pedal still feels spongy
after repeating this procedure, inspect the
brake system for external leaks.
31. Observe the brake warning indicator to determine whether or not the indicator remains
illuminated. 32. If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to
be driven until it is diagnosed and repaired.
W/O JL4
ABS Automated Bleed Procedure (w/o JL4)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
Important: This procedure may be performed on all vehicles EXCEPT those equipped with option
code JL4, Vehicle Stability Enhancement System (VSES).
Important: The base hydraulic brake system must be bled before performing this automated
bleeding procedure. If you have not yet performed the base hydraulic brake system bleeding
procedure, refer to Hydraulic Brake System Bleeding before proceeding.
1. Install a scan tool to the vehicle. 2. Start the engine and allow the engine to idle. 3. Depress the
brake pedal firmly and maintain steady pressure on the pedal. 4. Using the scan tool, begin the
automated bleed procedure. 5. Follow the instructions on the scan tool to complete the automated
bleed procedure. Release the brake pedal between each test sequence. 6. Turn the ignition OFF.
7. Remove the scan tool from the vehicle. 8. Fill the brake master cylinder reservoir to the
maximum-fill level with Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
9. Bleed the hydraulic brake system.
10. With the ignition OFF, apply the brakes 3-5 times, or until the brake pedal becomes firm, in
order to deplete the brake booster power reserve. 11. Slowly depress and release the brake pedal.
Observe the feel of the brake pedal. 12. If the brake pedal feels spongy, repeat the automated
bleeding procedure. If the brake pedal still feels spongy after repeating the automated
bleeding procedure inspect the brake system for external leaks.
13. Turn the ignition key ON, with the engine OFF; check to see if the brake system warning lamp
remains illuminated. 14. If the brake system warning lamp remains illuminated, DO NOT allow the
vehicle to be driven until it is diagnosed and repaired. Refer to
Symptoms - Hydraulic Brakes.
15. Drive the vehicle to exceed 13 kPa (8 mph) to allow ABS initialization to occur. Observe brake
pedal feel. 16. If the brake pedal feels spongy, repeat the automated bleeding procedure until a
firm brake pedal is obtained.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure > Page 8843
Brake Bleeding: Service and Repair Hydraulic Brake System Bleeding
Manual
Hydraulic Brake System Bleeding (Manual)
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder - after all air has been
purged from the front port of the master cylinder- loosen and separate the rear brake pipe from the
master cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent DOT-3 brake fluid from
a clean, sealed brake fluid container. Ensure that the brake master cylinder reservoir remains at
least half-full during this bleeding procedure. Add fluid as needed to maintain the proper level.
Clean the outside of the reservoir on and around the reservoir cap prior to removing the cap and
diaphragm.
5. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve. 6.
Install a transparent hose over the end of the bleeder valve. 7. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
8. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal. 9. Loosen the bleeder valve to purge air from the wheel hydraulic circuit.
10. Tighten the bleeder valve, then have the assistant slowly release the brake pedal. 11. Wait 15
seconds, then repeat steps 8-10 until all air is purged from the same wheel hydraulic circuit. 12.
With the right rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been
purged from the right rear hydraulic circuit install a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
13. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 14. With
the left rear wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the left rear hydraulic circuit- install a
proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
15. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 16. With
the right front wheel hydraulic circuit bleeder valve tightened securely- after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
17. Install a transparent hose over the end of the bleeder valve, then repeat steps 7-11. 18. After
completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4 wheel
hydraulic circuit bleeder valves are properly
tightened.
19. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
20. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 21. If the
brake pedal feels spongy, repeat the bleeding procedure again. If the brake pedal still feels spongy
after repeating the bleeding procedure,
perform the following steps: 21.1.
Inspect the brake system for external leaks.
21.2. Pressure bleed the hydraulic brake system in order to purge any air that may still be trapped
in the system.
22. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure > Page 8844
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
23. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Pressure
Hydraulic Brake System Bleeding (Pressure)
Tools Required ^
J29532 Diaphragm Type Brake Pressure Bleeder, or equivalent
^ J35589-A Brake Pressure Bleeder Adapter
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Place a clean shop cloth beneath the brake master cylinder to prevent brake fluid spills. 2. With
the ignition OFF and the brakes cool, apply the brakes 3-5 times, or until the brake pedal effort
increases significantly, in order to deplete the
brake booster power reserve.
3. If you have performed a brake master cylinder bench bleeding on this vehicle, or if you
disconnected the brake pipes from the master cylinder, you
must perform the following steps: 3.1.
Ensure that the brake master cylinder reservoir is full to the maximum-fill level. If necessary add
Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid
from a clean, sealed brake fluid container. If removal of the reservoir cap and diaphragm is
necessary, clean the outside of the reservoir on and around the cap prior to removal.
3.2. With the rear brake pipe installed securely to the master cylinder, loosen and separate the
front brake pipe from the front port of the brake master cylinder.
3.3. Allow a small amount of brake fluid to gravity bleed from the open port of the master cylinder.
3.4. Reconnect the brake pipe to the master cylinder port and tighten securely.
3.5. Have an assistant slowly depress the brake pedal fully and maintain steady pressure on the
pedal.
3.6. Loosen the same brake pipe to purge air from the open port of the master cylinder.
3.7. Tighten the brake pipe, then have the assistant slowly release the brake pedal.
3.8. Wait 15 seconds, then repeat steps 3.3-3.7 until all air is purged from the same port of the
master cylinder.
3.9. With the front brake pipe installed securely to the master cylinder- after all air has been purged
from the front port of the master cylinder - loosen and separate the rear brake pipe from the master
cylinder, then repeat steps 3.3-3.8.
3.10. After completing the final master cylinder port bleeding procedure, ensure that both of the
brake pipe-to-master cylinder fittings are properly tightened.
4. Fill the brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N
12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container. Clean the outside of the
reservoir on and around the reservoir cap prior to removing the cap and diaphragm.
5. Install the J35589-A to the brake master cylinder reservoir. 6. Check the brake fluid level in the
J29532, or equivalent. Add Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3
brake fluid from a clean, sealed brake fluid container as necessary to bring the level to
approximately the half-full point.
7. Connect the J29532, or equivalent, to the J35589-A. 8. Charge the J29532, or equivalent, air
tank to 175 - 205 kPa (25 - 30 psi). 9. Open the J29532, or equivalent, fluid tank valve to allow
pressurized brake fluid to enter the brake system.
10. Wait approximately 30 seconds, then inspect the entire hydraulic brake system in order to
ensure that there are no existing external brake fluid
leaks. Any brake fluid leaks identified require repair prior to completing this procedure.
11. Install a proper box-end wrench onto the RIGHT REAR wheel hydraulic circuit bleeder valve.
12. Install a transparent hose over the end of the bleeder valve. 13. Submerge the open end of the
transparent hose into a transparent container partially filled with Delco Supreme II, GM P/N
12377967 (Canadian
P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
14. Loosen the bleeder valve to purge air from the wheel hydraulic circuit. Allow fluid to flow until air
bubbles stop flowing from the bleeder, then
tighten the bleeder valve.
15. With the right rear wheel hydraulic circuit bleeder valve tightened securely - after all air has
been purged from the right rear hydraulic circuitinstall a proper box-end wrench onto the LEFT REAR wheel hydraulic circuit bleeder valve.
16. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 17. With
the left rear wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the left rear hydraulic circuit- install
a proper box-end wrench onto the RIGHT FRONT wheel hydraulic circuit bleeder valve.
18. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14. 19. With
the right front wheel hydraulic circuit bleeder valve tightened securely - after all air has been purged
from the right front hydraulic circuitinstall a proper box-end wrench onto the LEFT FRONT wheel hydraulic circuit bleeder valve.
20. Install a transparent hose over the end of the bleeder valve, then repeat steps 13-14.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure > Page 8845
21. After completing the final wheel hydraulic circuit bleeding procedure, ensure that each of the 4
wheel hydraulic circuit bleeder valves are properly
tightened.
22. Close the J29532, or equivalent, fluid tank valve, then disconnect the J29532, or equivalent,
from the J35589-A. 23. Remove the J35589-A from the brake master cylinder reservoir. 24. Fill the
brake master cylinder reservoir to the maximum-fill level with Delco Supreme II, GM P/N 12377967
(Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
25. Slowly depress and release the brake pedal. Observe the feel of the brake pedal. 26. If the
brake pedal feels spongy perform the following steps:
26.1. Inspect the brake system for external leaks.
26.2. Using a scan tool, perform the antilock brake system automated bleeding procedure to
remove any air that may have been trapped in the BPMV.
27. Turn the ignition key ON, with the engine OFF. Check to see if the brake system warning lamp
remains illuminated.
Important: If the brake system warning lamp remains illuminated, DO NOT allow the vehicle to be
driven until it is diagnosed and repaired.
28. If the brake system warning lamp remains illuminated, refer to Symptoms - Hydraulic Brakes.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Bleeding > System
Information > Service and Repair > ABS Automated Bleed Procedure > Page 8846
Brake Bleeding: Service and Repair Master Cylinder Bench Bleeding
Master Cylinder Bench Bleeding
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
1. Secure the mounting flange of the brake master cylinder in a bench vise so that the rear of the
primary piston is accessible. 2. Remove the master cylinder reservoir cap and diaphragm. 3. Install
suitable fittings to the master cylinder ports that match the type of flare seat required and also
provide for hose attachment. 4. Install transparent hoses to the fittings installed to the master
cylinder ports, then route the hoses into the master cylinder reservoir. 5. Fill the master cylinder
reservoir to at least the half-way point with Delco Supreme II, GM P/N 12377967 (Canadian P/N
992667), or equivalent
DOT-3 brake fluid from a clean, sealed brake fluid container.
6. Ensure that the ends of the transparent hoses running into the master cylinder reservoir are fully
submerged in the brake fluid. 7. Using a smooth, round-ended tool, depress and release the
primary piston as far as it will travel, a depth of about 25 mm (1 inch), several times.
Observe the flow of fluid coming from the ports. As air is bled from the primary and secondary
pistons, the effort required to depress the primary piston will increase and the amount of travel will
decrease.
8. Continue to depress and release the primary piston until fluid flows freely from the ports with no
evidence of air bubbles. 9. Remove the transparent hoses from the master cylinder reservoir.
10. Install the master cylinder reservoir cap and diaphragm. 11. Remove the fittings with the
transparent hoses from the master cylinder ports. Wrap the master cylinder with a clean shop cloth
to prevent brake
fluid spills.
12. Remove the master cylinder from the vise.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement
Brake Caliper: Service and Repair Brake Caliper Bracket Replacement
Front
Brake Caliper Bracket Replacement - Front
Removal Procedure
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
1. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
2. Remove the brake pads. 3. Remove the anti-rattle clips from the brake caliper bracket.
4. Remove the brake caliper bracket mounting bolts (2). 5. Remove the brake caliper bracket (1). 6.
Remove any contaminants or foreign material from the inside ends of the brake caliper bracket. 7.
Clean the mounting surface and threads of the brake caliper bracket.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8851
1. Install the brake caliper bracket (1). 2. Perform the following procedure before installing the
brake caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the caliper bracket mounting bolts (2).
^ Tighten the brake caliper bracket to knuckle bolt to 175 Nm (121 ft. lbs.) for the 15 Series.
^ Tighten the brake caliper bracket to knuckle bolts to 300 Nm (221 ft. lbs.) for 25 Series.
4. Install the anti-rattle clips to the brake caliper bracket. 5. Install the brake pads to the brake
caliper bracket.
^ Install the inner pad-1 wear indicator.
^ Install the inner pad-2 wear indicators.
6. Slide the brake pads in until they contact the rotor. 7. Install the brake caliper. 8. Install the tire
and wheel assembly. 9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance. 11. Slowly release the brake pedal. 12. Wait 15 seconds, then repeat steps 1-11 until a
firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Rear
Brake Caliper Bracket Replacement - Rear
Removal Procedure
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8852
1. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
2. Remove the brake pads. 3. Remove the anti-rattle clips from the brake caliper bracket.
4. Remove the brake caliper bracket mounting bolts (2). 5. Remove the brake caliper bracket (1). 6.
Remove any contaminants or foreign material from the inside ends of the brake caliper bracket. 7.
Clean the mounting surface and threads of the brake caliper bracket.
Installation Procedure
1. Install the brake caliper bracket (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8853
2. Perform the following procedure before installing the brake caliper bracket mounting bolts.
^ Remove all traces of the original adhesive patch.
^ Clean the threads of the bolt with denatured alcohol or equivalent and allow to dry.
^ Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the caliper bracket mounting bolts (2).
^ For vehicles equipped with JC5/JH5 brake systems, tighten the caliper bracket mounting bolts to
200 Nm (148 ft. lbs.).
^ For vehicles equipped with JH6 brake systems, tighten the caliper bracket mounting bolts to 165
Nm (122 ft. lbs.).
4. Install the anti-rattle clips to the brake caliper bracket. 5. Install the brake pads to the brake
caliper bracket. 6. Slide the brake pads in until they contact the rotor. 7. Install the brake caliper. 8.
Install the tire and wheel assembly. 9. Lower the vehicle.
10. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance. 11. Slowly release the brake pedal. 12. Wait 15 seconds, then repeat steps 7-8 until a
firm pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8854
Brake Caliper: Service and Repair Brake Caliper Overhaul
Front
Brake Caliper Overhaul - Front
Disassembly Procedure
Caution: Do not place your fingers in front of the piston in order to catch or protect the piston while
applying compressed air. This could result in serious injury.
1. Remove the brake caliper from the vehicle.
2. Place a thin piece of wood in front of the piston in order to prevent damage. Remove the piston
by directing compressed air into the brake hose
inlet fitting port of the brake caliper housing.
3. Remove the piston boot. 4. Remove the piston seal. 5. Remove the brake caliper bleed screw
cap. 6. Remove the brake caliper bleed screw. 7. Inspect the brake caliper bore and the piston seal
groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston
seal area, replace the brake caliper housing.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8855
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and
replace the brake caliper mounting bracket if
necessary.
9. Clean all of the residue from the brake pad guiding surfaces on the brake caliper housing and
the brake caliper mounting bracket.
10. Clean all of the parts not included in the repair kit with denatured alcohol. 11. Dry all of the
parts with filtered Unlubricated compressed air. 12. Blow out all passages in the brake caliper
housing and the brake caliper bleeder valve.
Assembly Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper bleed screw.
Tighten the brake caliper bleed screw to 12 Nm (106 inch lbs.).
2. Install the brake caliper bleed screw cap. 3. Lubricate the new piston seals and the brake caliper
bore seal grooves with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 4. Install new seals
into the brake caliper bore seal grooves. 5. Ensure that the seals are not twisted. 6. Lubricate the
brake caliper bores and the pistons with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 7.
Install the boot and piston.
7.1. Install the boot over the end of the piston so that the fold will face toward the brake caliper
housing piston bore opening.
7.2. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore.
7.3. Push down the piston to the bottom of the brake caliper bore.
7.4. Ensure the boot seats properly into the piston groove and into the groove in the brake caliper
bore.
7.5. Repeat steps 5 and 6 for the remaining piston.
8. Install the brake caliper to the vehicle.
Rear
Brake Caliper Overhaul - Rear
Disassembly Procedure
Caution: Do not place your fingers in front of the piston in order to catch or protect the piston while
applying compressed air. This could result in serious injury.
1. Remove the brake caliper from the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8856
2. Place a thin piece of wood in front of the piston in order to prevent damage. Remove the piston
by directing compressed air into the brake hose
inlet fitting port of the brake caliper housing.
3. Remove the piston boot. 4. Remove the piston seal. 5. Remove the brake caliper bleed screw
cap. 6. Remove the brake caliper bleed screw. 7. Inspect the brake caliper bore and the piston seal
groove for scoring and corrosion. If you find excessive scoring or corrosion around the piston
seal area, replace the brake caliper housing.
8. Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and
replace the brake caliper mounting bracket if
needed.
9. Clean all the residue from the brake pad guiding surfaces on the brake caliper housing and the
brake caliper mounting bracket.
10. Clean all the parts not included in the repair kit with denatured alcohol. 11. Dry all the parts with
filtered Unlubricated compressed air. 12. Blow out all passages in the brake caliper housing and
the brake caliper bleeder valve.
Assembly Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8857
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper bleed screw.
Tighten the brake caliper bleed screw to 12 Nm (106 inch lbs.).
2. Install the brake caliper bleed screw cap. 3. Lubricate the new piston seal and the brake caliper
bore seal groove with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 4. Install new the
seal into the brake caliper bore seal groove. 5. Ensure that the seal is not twisted. 6. Lubricate the
brake caliper bore and the piston with brake fluid, GM P/N 12388967 (Canadian P/N 992667). 7.
Install the boot and the piston.
7.1. Install the boot over the end of the piston so that the fold will face toward the brake caliper
housing piston bore opening.
7.2. Seat the boot into the brake caliper bore groove. Slide the piston into the brake caliper bore.
7.3. Push down the piston to the bottom of the brake caliper bore.
7.4. Ensure that the boot properly seats into the piston groove and into the groove in the brake
caliper bore.
7.5. Repeat steps 5 and 6 for the remaining piston.
8. Install the brake caliper to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8858
Brake Caliper: Service and Repair Brake Caliper Replacement
Front
Brake Caliper Replacement - Front
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level, no brake fluid needs to be
removed from the
reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level, remove brake fluid to the
midway point before proceeding.
4. Raise and support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel assembly.
6. Compress the brake caliper pistons.
^ Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
^ Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
^ Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end to prevent brake fluid
loss and contamination.
8. Remove the brake hose to caliper bolt from the brake caliper. 9. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
10. Remove the brake hose from the caliper.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8859
11. Remove the 2 brake caliper mounting bolts.
Caution: Do not depress the brake pedal with the brake rotors/calipers and/or the brake drums
removed. Damage to the brake system may result. If brake system damage occurs and is not
repaired, vehicle damage and/or personal injury or death may result
12. Remove the brake caliper from the brake caliper mounting bracket.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the brake caliper to the brake caliper mounting bracket.
2. Install the 2 brake caliper mounting bolts.
Tighten the bolts to 108 Nm (80 ft. lbs.).
3. Remove the rubber cap or plug from the exposed brake hose fitting end.
Important: Install 2 New copper brake hose gaskets.
4. Assemble the 2 New copper brake hose gaskets and the brake hose to caliper bolt to the brake
hose.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8860
5. Install the brake hose to caliper bolt to the brake caliper.
Tighten the brake hose to caliper bolt to 40 Nm (30 ft. lbs.).
6. Bleed the hydraulic brake system. 7. Install the tire and wheel assembly. 8. Lower the vehicle. 9.
Fill the master cylinder reservoir to the proper level with clean brake fluid.
Rear
Brake Caliper Replacement - Rear
Removal Procedure
1. Inspect the fluid level in the brake master cylinder reservoir. 2. If the brake fluid level is midway
between the maximum-full point and the minimum allowable level then no brake fluid needs to be
removed from
the reservoir before proceeding.
3. If the brake fluid level is higher than midway between the maximum-full point and the minimum
allowable level then remove brake fluid to the
midway point before proceeding.
4. Raise and support the vehicle. Refer to Vehicle Lifting. 5. Remove the tire and wheel assembly.
6. Compress the brake caliper pistons.
^ Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
^ Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
^ Remove the C-clamp from the caliper.
7. Clean all dirt and foreign material from the brake hose end.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end to prevent brake fluid
loss and contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8861
8. Remove the brake hose to caliper bolt from the brake caliper. 9. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
10. Remove the caliper guide pin bolts. 11. Remove the brake caliper from the vehicle. 12. Inspect
the caliper assembly.
Installation Procedure
Important: Use denatured alcohol to clean the outside surface of caliper boots before installing new
brake pads.
1. If you are installing new brake pads use a C-clamp in order to compress the pistons to the
bottom of the caliper bores. Use the old brake pad, a
metal plate or a wooden block across the face of the pistons in order to protect the pistons and the
caliper boots.
Important: Use a small flat-bladed tool and lift the inner edge of the caliper boots next to both
pistons to release any trapped air.
2. Ensure that the caliper boots are below the level of the face of both pistons.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8862
3. Install the brake caliper to the brake caliper mounting bracket. 4. Perform the following
procedure before installing the caliper guide pin bolts.
4.1. Remove all traces of the original adhesive patch.
4.2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
4.3. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
5. Install the brake caliper mounting bolts.
Notice: Refer to Fastener Notice in Service Precautions.
6. Tighten the brake caliper guide pin bolts - rear 15 Series.
Tighten the to 42 Nm (31 ft. lbs.).
7. Remove the rubber cap or plug from the exposed brake hose fitting end.
Important: Install 2 New copper brake hose gaskets.
8. Assemble the 2 New copper brake hose gaskets and the brake hose to caliper bolt to the brake
hose.
9. Connect the brake hose at the caliper by installing the brake hose to caliper bolt.
Tighten the brake hose to caliper bolt to 40 Nm (30 ft. lbs.).
10. Bleed the hydraulic brake system. 11. Install the tire and wheel assembly. 12. Lower the
vehicle. 13. Fill the master cylinder reservoir to the proper level with clean brake fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8863
Brake Caliper: Service and Repair Disc Brake Hardware Replacement
Front
Disc Brake Hardware Replacement - Front
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
4. Remove the disc brake pads from the disc brake caliper mounting bracket. 5. Remove the disc
brake pad retainers from the disc brake caliper mounting bracket. 6. Inspect the disc brake
hardware.
7. Remove the caliper pin boots (4) from the disc brake caliper mounting bracket (3).
Installation Procedure
1. Lubricate the front brake caliper bushings, bolts and seals with high temperature silicone brake
lubricant.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8864
2. Install the caliper pin boots (4) to the disc brake caliper mounting bracket (3).
3. Install the disc brake pad retainers to the disc brake caliper mounting bracket. 4. Install the disc
brake pads to the disc brake caliper mounting bracket. 5. Install the disc brake caliper to the caliper
mounting bracket. 6. With the engine OFF, gradually apply the brake pedal approximately 2/3 of its
travel distance. 7. Slowly release the brake pedal. 8. Wait 15 seconds, then repeat steps 7-8 until a
firm brake pedal is obtained. This will properly seat the brake caliper pistons and brake pads.
Rear
Disc Brake Replacement - Rear
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting.
2. Remove the tire and wheel assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Caliper > Component
Information > Service and Repair > Brake Caliper Bracket Replacement > Page 8865
Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is
separated from it's mount and the hydraulic flexible brake hose is still connected. Failure to support
the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which
may cause damage to the brake hose and in turn may cause a brake fluid leak.
3. Remove the caliper from the mounting bracket and support the caliper with heavy mechanic's
wire or equivalent. DO NOT disconnect the
hydraulic brake flexible hose from the caliper.
4. Remove the disc brake pads from the disc brake caliper bracket. 5. Remove the disc brake pad
retainers from the disc brake caliper bracket.
6. Remove the caliper pins (5) from the disc brake caliper mounting bracket (3). 7. Remove the
caliper pin boots (4) from the disc brake caliper mounting bracket. 8. Inspect the disc brake
hardware.
Installation Procedure
1. Lubricate the brake caliper, bushings, bolts and seals with high temperature silicone brake
lubricant.
2. Install the caliper pin boots (4) to the disc brake caliper mounting bracket. 3. Install the caliper
pins (5) to the disc brake caliper mounting bracket (3). 4. Install the disc brake pad retainers to the
disc brake caliper bracket. 5. Install the disc brake pads to the disc brake caliper bracket. 6. Install
the disc brake caliper to the mounting bracket. 7. With the engine OFF, gradually apply the brake
pedal approximately 2/3 of its travel distance. 8. Slowly release the brake pedal. 9. Wait 15
seconds, then repeat steps 7-8 until a firm brake pedal is obtained. This will properly seat the brake
caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid > Component
Information > Specifications
Brake Fluid: Specifications
Hydraulic Brake System Delco Supreme 11 Brake Fluid GM Part No. 12377967 (Canadian P/N
992667) or equivalent DOT-3 brake fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Level Sensor/Switch
> Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Level Sensor/Switch
> Component Information > Diagrams > Page 8872
Brake Fluid Level Sensor/Switch: Service and Repair
Master Cylinder Fluid Level Sensor Replacement
Removal Procedure
1. Disconnect the electrical connector from the fluid level sensor.
2. Remove the fluid level sensor (1). Use a needle nose pliers in order to compress the locking tabs
at the opposite side of the master cylinder.
Installation Procedure
1. Install the fluid level sensor (1) until the locking tabs snap into place. 2. Connect the electrical
connector to the fluid level sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Specifications
Brake Fluid Pressure Sensor/Switch: Specifications
Brake Fluid Pressure Sensor (JL4)
...........................................................................................................................................................
16 Nm (12 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Locations > MPA Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Locations > MPA Switch > Page 8878
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
Brake Fluid Pressure Sensor/Switch: Service and Repair Brake Fluid Pressure Sensor
Replacement
Brake Fluid Pressure Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the alien bolt (2) from the Brake Pressure Modulator Valve (BPMV) mounting bracket
(3) located on the sensor side. 3. Raise the BPMV to access the brake fluid pressure sensor.
4. Disconnect the electrical connector from the brake fluid pressure sensor.
Important: The replacement of the old brake fluid pressure sensor must be performed quickly to
reduce the amount of fluid that is lost during the procedure.
5. Use a wrench to keep the brake fluid pressure sensor collar from turning (1).
Remove the brake fluid pressure sensor (2) from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement > Page 8881
Notice: Refer to Fastener Notice in Service Precautions.
1. Quickly install the new brake fluid pressure sensor (2) to the BPMV as soon as the old sensor
has been removed.
Use a wrench to keep the brake fluid pressure sensor collar from turning (1). Tighten the brake fluid
pressure sensor to 16 Nm (12 ft. lbs.).
2. Install the alien bolt (2) to the Brake Pressure Modulator Valve (BPMV) mounting bracket (3).
Tighten the alien bolt to 9 Nm (7 ft. lbs.).
3. Connect the electrical connector to the brake fluid pressure sensor. 4. Lower the vehicle. 5.
Check and fill the brake fluid level in the master cylinder.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement > Page 8882
Brake Fluid Pressure Sensor/Switch: Service and Repair Pressure Accumulator Switch
Replacement
Pressure Accumulator Switch Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the bolts (2) that secure the Brake Pressure Modulator Valve (BPMV) (1) to the
mounting bracket (3).
3. Disconnect the electrical connector from the pressure accumulator switch.
4. Position the BPMV to be able to remove the pressure accumulator switch. 5. Remove the
pressure accumulator switch from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Fluid Pressure
Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement > Page 8883
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the pressure accumulator switch to the BPMV.
Tighten the pressure accumulator switch to 3 Nm (30 inch lbs.).
2. Connect the electrical connector to the pressure accumulator switch.
3. Install the Brake Pressure Modulator Valve (BPMV) (1) and the bolts (2) to the mounting bracket
(3).
Tighten the bolts to 9 Nm (7 ft. lbs.).
4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Specifications
Brake Hose/Line: Specifications
Brake Hose to Caliper Bolt, Front
.............................................................................................................................................................
40 Nm (30 ft. lbs.) Brake Hose to Caliper Bolt, Rear
..............................................................................................................................................................
40 Nm (30 ft. lbs.) Brake Pipe Fittings .................................................................................................
................................................................................ 25 Nm (18 ft. lbs.) Hose Bracket to Frame Bolt ..
..............................................................................................................................................................
. 12 Nm (106 inch lbs.) Hose Bracket to Rear Axle Bolt
...........................................................................................................................................................
12 Nm (106 inch lbs.) Hose Bracket to Anchor Plate Bolt
............................................................................................................................................................
25 Nm (18 ft. lbs.) Hose Bracket to Knuckle Bolt
..............................................................................................................................................................
12 Nm (106 inch lbs.) Hose Bracket to Upper Control Arm
Bolt................................................................................................................................................. 9
Nm (80 inch lbs.) Front Brake Lines to BPMV .....................................................................................
................................................................................ 25 Nm (18 ft. lbs.) Master Cylinder Brake Lines
to BPMV
.................................................................................................................................................... 25
Nm (18 ft. lbs.) Rear Brake Line to BPMV ...........................................................................................
............................................................................ 25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement
Brake Hose/Line: Service and Repair Brake Pipe Replacement
Brake Pipe Replacement
Removal Procedure
Caution: Refer to Brake Pipe Replacement Caution in Service Precautions.
Important: Brake pipes that run parallel to each other must maintain a 6 mm (1/4 inch) clearance.
1. Disconnect the brake pipe fittings. 2. Remove the brake pipe fasteners from the vehicle. 3.
Remove the brake pipe from the vehicle.
Installation Procedure
1. Bend the brake pipe to achieve proper fit. 2. Install the brake pipe to the vehicle. Maintain a
clearance of 19 mm (3/4 inch) for all moving or vibrating components. 3. Install the brake pipe
fasteners to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
4. Connect the brake pipe fittings.
^ Tighten the brake pipe fittings to the BPMV or the wheel jounce hoses to 25 Nm (18 ft. lbs.).
^ Tighten the brake pipe fittings to the master cylinder to 25 Nm (18 ft. lbs.).
^ Bleed the hydraulic brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8889
Brake Hose/Line: Service and Repair Hose
Front
Brake Hose Replacement - Front
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Clean all dirt and foreign material from the brake hose end and brake pipe fitting.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end in order to prevent
brake fluid loss and contamination.
4. Use a backup wrench on the brake hose fitting end (2), disconnect the brake pipe fitting end (1)
from the brake hose (2), then cap or plug the brake
pipe fitting end.
5. Remove the brake hose retaining clip (3) from the brake hose mounting bracket.
6. Remove the brake hose bracket bolt from the upper control arm. 7. Remove the brake hose
bracket bolt from the steering knuckle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8890
8. Remove the brake hose to caliper bolt from the brake caliper. 9. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
Installation Procedure
Important: Install 2 New copper brake hose gaskets.
1. Assemble the 2 New copper brake hose gaskets and the brake hose bolt to the brake hose.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the brake hose to caliper bolt-front, and 2 New washers to the brake caliper.
Tighten the bolt to 40 Nm (30 ft. lbs.).
Important: The brake hose must not be twisted. Make sure the brake hose is not in contact with any
suspension component.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8891
3. Install the brake hose bracket bolt and the bracket to the steering knuckle.
Tighten the bolt to 9 Nm (80 inch lbs.).
4. Install the brake hose bracket bolt and the bracket to the upper control arm.
Tighten the bolt to 9 Nm (80 inch lbs.).
5. Install the brake hose into the brake hose bracket.
6. Install the brake hose retaining clip (3). 7. Remove the rubber cap or plug from the brake pipe
fitting end. 8. Connect the brake pipe fitting end (1) to the brake hose (2):
^ Use a backup wrench on the brake hose fitting end (2).
^ Do not bend the mounting bracket or the brake pipe. Tighten the brake pipe fitting end (1) to 25
Nm (18 ft. lbs.).
9. Bleed the hydraulic brake system.
10. Install the tire and wheel assembly.
Important: Ensure that the brake hose does not make contact with any part of the suspension or
the tire/wheel assembly. Check the brake hose in extreme right and left turn conditions. If the brake
hose makes contact remove the brake hose and correct the condition.
11. Lower the vehicle.
Rear Caliper
Brake Hose Replacement - Rear (Caliper)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Clean all dirt and foreign material from the brake hose end and brake pipe fitting.
Important: Install a rubber cap or plug to the exposed brake pipe fitting end in order to prevent
brake fluid loss and contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8892
4. Use a backup wrench on the brake hose fitting end (1), disconnect the brake pipe fitting end (2)
from the brake hose (1) then cap or plug the brake
pipe fitting end.
5. Remove the brake hose retaining clip (3) from the brake hose mounting bracket. 6. Remove the
brake hose (1) from the mounting bracket.
7. Remove the brake hose to caliper bolt from the brake caliper. 8. Remove and discard the 2
copper brake hose gaskets. These gaskets may be stuck to the brake caliper housing or the brake
hose end.
Installation Procedure
Important: Install 2 New copper brake hose gaskets.
1. Assemble the 2 New copper brake hose gaskets and the brake hose bolt to the brake hose.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8893
2. Install the brake hose to caliper bolt-rear, and 2 New washers to the brake caliper.
Tighten the bolt to 40 Nm (30 ft. lbs.).
Important: The brake hose must not be twisted. Make sure the brake hose is not in contact with any
suspension component.
3. Install the brake hose (1) into the mounting bracket. 4. Install the brake hose retaining clip (3). 5.
Remove the rubber cap or plug from the exposed brake pipe fitting end. 6. Connect the brake pipe
fitting end (2) to the brake hose (1):
^ Use a backup wrench on the brake hose fitting end (1).
^ Do not bend the mounting bracket or the brake pipe. Tighten the brake pipe fitting end (2) to 25
Nm (18 ft. lbs.).
7. Bleed the hydraulic brake system. 8. Install the tire and wheel assembly.
Important: Ensure that the brake hose does not make contact with any part of the suspension or
the tire/wheel assembly. If the brake hose makes contact remove the brake hose and correct the
condition.
9. Lower the vehicle.
Rear Jounce
Brake Hose Replacement - Rear (Jounce)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Clean all dirt and foreign material from
the brake hose and brake pipe fittings.
Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent
brake fluid loss and contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Hose/Line > Component
Information > Service and Repair > Brake Pipe Replacement > Page 8894
3. Use a backup wrench on the hose fitting, disconnect the brake pipe fitting from the brake hose,
then cap or plug the brake pipe fitting end. 4. Remove the brake hose retaining clip from the hose
mounting bracket. 5. Remove the jounce hose from the bracket.
Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent
brake fluid loss and contamination.
6. Disconnect the 2 rear brake pipes from the junction block on the rear axle and cap or plug the
brake pipe fitting ends. 7. Remove the junction block retaining bolt from the axle. 8. Remove the
brake hose from the vehicle.
Installation Procedure
1. Install the rear brake hose
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the junction block retaining bolt to the axle.
Tighten the bolt to 12 Nm (106 inch lbs.).
3. Remove the caps or plugs from the rear brake pipes and connect the pipes to the junction block
on the axle.
Tighten the fitting to 25 Nm (18 ft. lbs.).
Important: The hose must not be twisted. Make sure the hose is not in contact with any suspension
component.
4. With the weight of the vehicle on the suspension, install the brake hose into the bracket. 5. Install
the jounce hose retaining clip. 6. Remove the rubber cap or plug from the exposed brake pipe
fitting end. 7. Connect the brake pipe fitting to the brake hose:
^ Use a backup wrench on the hose fitting.
^ Do not bend the bracket or the pipe. Tighten the fitting to 25 Nm (18 ft. lbs.).
8. Ensure that the hose does not make contact with any part of the suspension. If the hose makes
contact, remove the hose and correct the condition. 9. Bleed the hydraulic brake system.
10. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Specifications
Hydraulic Control Assembly - Antilock Brakes: Specifications
Brake Pressure Modulator Bleeder Valves
............................................................................................................................................. 9 Nm (80
inch lbs.) EHCU Bracket to Frame Bolt ...............................................................................................
.................................................................... 25 Nm (18 ft. lbs.) EHCU to Bracket Allen Bolt ..............
.......................................................................................................................................................... 9
Nm (7 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4
Hydraulic Control Assembly - Antilock Brakes: Service and Repair W/ JL4
Brake Pressure Modulator Valve (BPMV) Replacement (w/ JL4)
Removal Procedure
Important: The area around the Electric Hydraulic Control Unit (EHCU) MUST be free from loose
dirt to prevent contamination of disassembled ABS components.
1. Thoroughly wash all contaminants from around the EHCU.
2. Disconnect the 2 electrical harness connectors from the Electronic Brake Control Module
(EBCM) (1).
3. Disconnect the electrical connector from the pressure accumulator switch.
4. Disconnect the electrical connector from the brake fluid pressure sensor.
Important: Make sure that brake lines are tagged and kept in order for proper reassembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8900
5. Disconnect the brake lines from the Brake Pressure Modulator Valve (BPMV) (2). 6. Remove the
bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5). 7. Remove the EHCU from
the vehicle.
8. Remove the bolts (4) securing the BPMV (1) to the EHCU mounting bracket (3). 9. Remove the
4 T-25 torx bolts from the EBCM (2).
10. Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.
11. Remove the accumulator switch.
12. Remove the brake fluid sensor (2).
Important: Do not reuse the EBCM mounting bolts. Always install new bolts.
13. Clean the EBCM to BPMV mounting surfaces with a clean cloth.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8901
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the pressure accumulator switch to the BPMV.
Tighten the switch to 3 Nm (30 inch lbs.).
2. Install the brake fluid pressure sensor (2) using a backup wrench to keep the brake fluid
pressure sensor collar (1) from turning.
Tighten the sensor to 16 Nm (12 ft. lbs.).
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
3. Install the EBCM (2) onto BPMV (1). 4. Install the four EBCM bolts.
Important: Do not reuse the old mounting bolts. Always install new EBCM bolts with the new
BPMV.
Tighten the bolts to 5 Nm (39 inch lbs.) in an X-pattern.
5. Connect the brake fluid pressure sensor and pressure accumulator switch electrical harnesses.
6. Install the BPMV (1) to EHCU bracket (3). 7. Install the BPMV to bracket retaining bolts (4).
Tighten the bolts to 9 Nm (7 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8902
8. Install the EHCU to the vehicle frame (5). 9. Install the EHCU bracket bolts.
Tighten the EHCU bracket bolts (4) to 25 Nm (18 ft. lbs.).
10. Connect the 2 electrical harness connectors to the EBCM (1).
Important: The brake pipes are held in place by a plastic bracket mounted to the frame. Make sure
that the brake pipes stay in the correct place for proper reassembly.
11. Install the brake pipes to the BPMV (2).
Tighten the brake pipe fittings to 25 Nm (18 ft. lbs.).
12. Bleed the brake system. 13. Bleed the brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8903
Hydraulic Control Assembly - Antilock Brakes: Service and Repair W/O JL4
Brake Pressure Modulator Valve (BPMV) Replacement (w/o JL4)
Removal Procedure
Important: The area around the electric hydraulic control unit (EHCU) MUST be free from loose dirt
to prevent contamination of disassembled ABS components.
1. Thoroughly wash all contaminants from around the EHCU.
2. Disconnect the 3 electrical harness connectors from the electronic brake control module (EBCM)
(1).
Important: Make sure that brake lines are tagged and kept in order for proper reassembly.
3. Disconnect the brake lines from the brake pressure modulator valve (BPMV) (2). 4. Remove the
bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5). 5. Remove the EHCU from
the vehicle.
6. Remove the bolts (4) securing the BPMV (1) to the EHCU mounting bracket (3). 7. Disconnect
the 2 way ABS pump motor connector. 8. Remove the 4 T-25 TORX bolts from the EBCM (2). 9.
Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.
Important: Do not reuse the EBCM mounting bolts. Always install new bolts.
10. Clean the EBCM to BPMV mounting surfaces with a clean cloth.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Hydraulic Control Assembly Antilock Brakes > Component Information > Service and Repair > W/ JL4 > Page 8904
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
1. Install the EBCM (2) onto BPMV (1).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the four EBCM bolts.
Important: Do not reuse the old mounting bolts. Always install new EBCM bolts with the new
BPMV.
Tighten the 4 bolts to 5 Nm (39 inch lbs.) in an X-pattern.
3. Connect the 2 way ABS pump motor connector to the EBCM. 4. Install the BPMV (1) to EHCU
bracket (3). 5. Install the BPMV (1) to bracket retaining bolts (4).
Tighten the bolts to 9 Nm (7 ft. lbs.).
6. Install the EHCU to the vehicle frame (5).
Tighten the three EHCU bracket bolts (4) to 25 Nm (18 ft. lbs.).
7. Connect the 2 electrical harness connectors to the EBCM (1).
Important: The brake pipes are held in place by a plastic bracket mounted to the frame. Make sure
that the brake pipes stay in the correct place for proper reassembly.
8. Install the 5 brake pipes to the BPMV (6).
Tighten the brake pipe fittings to 25 Nm (18 ft. lbs.).
9. Bleed the brake system.
10. Bleed the brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Specifications
Brake Master Cylinder: Specifications
Master Cylinder Mounting Nuts ...........................................................................................................
.................................................... 36 Nm (27 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul
Brake Master Cylinder: Service and Repair Master Cylinder Overhaul
Master Cylinder Overhaul
Disassembly Procedure
1. Remove the brake master cylinder from the vehicle. 2. Secure the mounting flange of the brake
master cylinder in a bench vise so that the rear of the primary piston is accessible. 3. Clean the
outside of the master cylinder reservoir on and around the reservoir cap prior to removing the cap
and diaphragm. 4. Remove the reservoir cap and diaphragm from the reservoir. 5. Inspect the
reservoir cap and diaphragm for the following conditions. If any of these conditions are present,
replace the affected components.
^ Cuts or cracks
^ Nicks or deformation
6. Remove the master cylinder reservoir from the master cylinder.
7. Using a smooth, round-ended tool, depress the primary piston (2) and remove the piston
retainer. 8. Remove the primary piston assembly from the cylinder bore. 9. Plug the cylinder inlet
ports and the rear outlet port. Apply low pressure, non-lubricated, filtered air into the front outlet
port, in order the remove
the secondary piston (1) with the primary (6) and secondary (5) seals, and the return spring.
10. Discard the primary piston assembly, the piston retainer, and the seals and seal retainer from
the secondary piston.
Assembly Procedure
Important: Do not use abrasives to clean the brake master cylinder bore.
1. Clean the interior and exterior of the master cylinder, the secondary piston (1), and the return
spring in denatured alcohol, or equivalent. 2. Inspect the master cylinder bore, inlet and outlet
ports, the secondary piston (1), and the return spring for cracks, scoring, pitting, and/or corrosion.
Replace the master cylinder if any of these conditions exist.
3. Dry the master cylinder and the individual components with non-lubricated, filtered air. 4.
Lubricate the master cylinder bore, the secondary piston (1), the return spring, and all of the
individual overhaul components with Delco Supreme
II, GM P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed
brake fluid container.
5. Assemble the lubricated, new primary seal (6) and retainer and new secondary seal (5) onto the
secondary piston.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8910
6. Install the lubricated return spring and secondary piston assembly (1) into the cylinder bore. 7.
Install the lubricated, new primary piston assembly (2) into the cylinder bore. 8. Using a smooth,
round-ended tool, depress the primary piston (2) and install the new piston retainer. 9. Install the
master cylinder reservoir to the master cylinder.
10. Install the reservoir cap and diaphragm to the reservoir. 11. Install the master cylinder to the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8911
Brake Master Cylinder: Service and Repair Master Cylinder Replacement
Vacuum Boost
Master Cylinder Replacement (Vacuum Boost)
Removal Procedure
1. Apply the park brake and block the wheels.
2. Disconnect the electrical connector from the brake fluid level sensor. 3. Disconnect the brake
pipes from the master cylinder.
Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent
brake fluid loss and contamination.
4. Plug the open brake pipe ends.
5. Remove the master cylinder mounting nuts. 6. Remove the master cylinder from the vehicle. 7.
Remove the master cylinder reservoir.
Installation Procedure
1. Install the master cylinder reservoir. 2. Bench bleed the master cylinder. 3. Install the master
cylinder to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8912
4. Install the master cylinder mounting nuts.
Tighten the nuts to 36 Nm (27 ft. lbs.).
5. Remove the rubber cap or plug from the exposed brake pipe fitting ends.
6. Connect the brake pipes.
Tighten the fittings to 25 Nm (18 ft. lbs.).
7. Connect the electrical connector to the brake fluid level sensor. 8. Bleed the hydraulic brake
system. 9. Release the park brake and unblock the wheels.
Hydraulic Boost
Master Cylinder Replacement (Hydraulic Boost)
Removal Procedure
1. Apply the park brake and block the wheels. 2. Disconnect the electrical connector from the brake
fluid level sensor.
Important: Install a rubber cap or plug to the exposed brake pipe fitting ends in order to prevent
brake fluid loss and contamination.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8913
3. Plug the open brake pipe ends. 4. Remove the master cylinder mounting nuts. 5. Remove the
master cylinder from the vehicle. 6. Remove the master cylinder reservoir.
Installation Procedure
1. Install the master cylinder reservoir. 2. Bench bleed the master cylinder. 3. Install the master
cylinder to the vehicle.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the master cylinder mounting nuts.
Tighten the nuts to 36 Nm (27 ft. lbs.).
5. Remove the rubber cap or plug from the exposed brake pipe fitting ends. 6. Connect the brake
pipes.
Tighten the pipe fittings to 25 Nm (18 ft. lbs.).
7. Connect the electrical connector to the brake fluid level sensor. 8. Bleed the hydraulic brake
system. 9. Release the park brake and unblock the wheels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8914
Brake Master Cylinder: Service and Repair Master Cylinder Reservoir Replacement
Master Cylinder Reservoir Replacement
Removal Procedure
1. Apply the park brake and block the wheels. 2. Remove the master cylinder. 3. Drain the master
cylinder reservoir. 4. Secure the master cylinder in a vise. Do not clamp the master cylinder body,
secure only at the flange.
5. Remove the brake fluid level sensor by carefully depressing the retaining tabs and pushing the
sensor through the reservoir. 6. Carefully remove the reservoir retaining pins.
7. Remove the reservoir from the master cylinder by pulling the reservoir straight up and away from
the cylinder. 8. Remove the seals from the master cylinder.
Installation Procedure
1. Inspect the reservoir for cracks or deformation. If found, replace the reservoir. 2. Clean the
reservoir with denatured alcohol, or equivalent. 3. Dry the reservoir with non-lubricated, filtered air.
4. Lubricate the new seals and the outer surface area of the reservoir-to-housing barrels with Delco
Supreme II, GM P/N 12377967 (Canadian P/N
992667) or equivalent DOT-3 brake fluid, from a clean, sealed brake fluid container.
5. Install the lubricated seals, make sure they are fully seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8915
6. Install the reservoir to the master cylinder by pressing the reservoir straight down on the master
cylinder until the pin holes are aligned.
7. Carefully install the reservoir retaining pins to secure the reservoir. 8. Place the brake fluid level
sensor into the reservoir, press into place to secure the sensor retaining tabs. 9. Remove the
master cylinder from the vice.
10. Install the master cylinder. 11. Release the park brake. 12. Bleed the hydraulic brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Brake Master Cylinder >
Component Information > Service and Repair > Master Cylinder Overhaul > Page 8916
Brake Master Cylinder: Service and Repair Master Cylinder Reservoir Filling
Master Cylinder Reservoir Filling
Notice: When adding fluid to the brake master cylinder reservoir, use only Delco Supreme II, GM
P/N 12377967 (Canadian P/N 992667), or equivalent DOT-3 brake fluid from a clean, sealed brake
fluid container. The use of any type of fluid other than the recommended type of brake fluid, may
cause contamination which could result in damage to the internal rubber seals and/or rubber linings
of hydraulic brake system components.
Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Service
Precautions.
1. Visually inspect the brake fluid level through the brake master cylinder reservoir. 2. If the brake
fluid level is at or below the half-full point during routine fluid checks, the brake system should be
inspected for wear and possible
brake fluid leaks.
3. If the brake fluid level is at or below the half-full point during routine fluid checks, and an
inspection of the brake system did not reveal wear or
brake fluid leaks, the brake fluid may be topped-off up to the maximum-fill level.
4. If brake system service was just completed, the brake fluid may be topped-off up to the
maximum-fill level. 5. If the brake fluid level is above the half-full point, adding brake fluid is not
recommended under normal conditions. 6. If brake fluid is to be added to the master cylinder
reservoir, clean the outside of the reservoir on and around the reservoir cap prior to removing
the cap and diaphragm. Use only Delco Supreme II, GM P/N 12377967 (Canadian P/N 992667), or
equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Hydraulic System, Brakes > Wheel Cylinder > Component
Information > Technical Service Bulletins > Brakes - Wheel Cylinder Inspection Guidelines
Wheel Cylinder: Technical Service Bulletins Brakes - Wheel Cylinder Inspection Guidelines
Bulletin No.: 03-05-24-001A
Date: March 21, 2005
INFORMATION
Subject: Service Information Regarding Rear Brake Drum Wheel Cylinder Inspections
Models: 2005 and Prior GM Passenger Cars and Trucks 2005 and Prior Saturn Vehicles
with Rear Drum Brakes
Supercede:
This bulletin is being revised add model years and include all GM vehicles. Please discard
Corporate Bulletin Number 03-05-24-001 (Section 03 - Suspension).
This bulletin provides information on proper inspection of rear drum brake wheel cylinders.
Important:
It is not recommended that dust boots be removed during inspection processes as dirt and debris
could contaminate the wheel cylinder bore causing premature wear of the wheel cylinder. In
addition, most bores should look damp and some lubricant may drip out from under the boot as a
result of lubricant being present.
All rear drum brake wheel cylinders are assembled with a lubricant to aid in assembly, provide an
anti-corrosion coating to the cylinder bore, and lubricate internal rubber components. As a result of
this lubrication process, it is not uncommon for some amount of lubricant to accumulate at the ends
of the cylinder under the dust boot.
Over time, the lubricant may work its way to the outside of the boot and cause an area of the boot
to look damp. Evidence of a damp area on the boot does not indicate a leak in the cylinder.
However, if there is excessive wetness (i.e. drips) coming from the boot area of the wheel cylinder,
it could indicate a brake hydraulic fluid leak requiring wheel cylinder replacement. (Refer to the
Wheel Cylinder Replacement procedures in the appropriate Service Manual.)
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Actuator >
Component Information > Service and Repair
Parking Brake Actuator: Service and Repair
Park Brake Actuator Replacement
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting. 3. Remove
the tire and wheel assembly.
4. Relieve the tension from the park brake cables by loosening the nut at the equalizer. 5. Remove
the rear park brake cable from the park brake actuator lever. 6. Remove the park brake cable from
the mounting bracket by depressing the locking tabs. 7. Remove the rotor. 8. Remove the axle
shaft. 9. Remove the park brake shoe.
10. Remove the backing plate bolts. 11. Remove the park brake actuator lever housing from the
backing plate.
Installation Procedure
1. Install the park brake actuator lever housing to the backing plate. 2. Perform the following
procedure before installing the backing plate bolts.
2.1. Remove all traces of the original adhesive patch.
2.2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
2.3. Apply Threadlocker GM P/N 12345493 (Canadian P/N 10953488) to the threads of the bolt.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the backing plate bolts.
Tighten the backing plate bolts to 135 Nm (100 ft. lbs.).
4. Install the park brake shoe. 5. Install the axle shaft. 6. Adjust the park brake shoe.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Actuator >
Component Information > Service and Repair > Page 8925
7. Install the rotor. 8. Install the park brake cable to the mounting bracket until the locking tabs snap
into place. 9. Install the rear park brake cable to the park brake actuator lever.
10. Tighten the nut to the intermediate cable at the equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
11. Install the tire and wheel assembly. 12. Remove the safety stands. 13. Lower vehicle. 14.
Adjust park brake cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Specifications
Parking Brake Cable: Specifications
Park Brake Cable Guide to Frame Bolt
............................................................................................................................................... 12 Nm
(106 inch lbs.) Park Brake Cable to Rear Axle Clip Bolt
................................................................................................................................................. 25 Nm
(18 ft. lbs.) Park Brake Cable to Shock Absorber Bracket Bolt
.................................................................................................................................. 25 Nm (18 ft.
lbs.) Cable Support Bracket Nuts ........................................................................................................
............................................................. 85 Nm (64 ft. lbs.) Intermediate Cable Threaded Rod Nut
................................................................................................................................................. 3.5 Nm
(31 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Specifications > Page 8929
Parking Brake Cable: Adjustments
Disabling the Park Brake Cable Automatic Adjuster
Before any components of the parking brake system are serviced, the following procedure must be
followed. Two technicians are required to perform this procedure: one inside the vehicle and one
outside the vehicle.
1. Raise and support the vehicle.
2. Hold the pedal in the FULL upward position.
3. Pull rearward on the front park brake cable until the pedal drum (2) reaches its full reset position.
4. Insert a scribe or the shaft of a thin screwdriver (1) on an upward angle through the hole in the
front of the pedal assembly, past the retracted pedal
drum, and into the hole in the back of the pedal assembly (3).
5. Slowly release the cable.
6. Remove the component that requires service.
Enabling the Park Brake Cable Automatic Adjuster
If the park brake automatic adjuster has been disabled, the following two person procedure must
be performed.
1. Hold the park brake pedal in the FULL upward position.
2. Pull rearward on the front park brake cable until the tension is released from the scribe or nail (1)
installed through the holes in the pedal assembly.
3. Remove the scribe or screwdriver (1).
4. Slowly release the park brake cable until it returns to its original position.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Specifications > Page 8930
5. Release the park brake pedal.
6. Lower the vehicle.
7. Apply and release the park brake pedal to ensure that there is no binding or sticking.
Please refer to Parking Brake Pedal Adjustments. See: Parking Brake Pedal/Adjustments
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement
Parking Brake Cable: Service and Repair Park Brake Cable Replacement
Intermediate
Park Brake Cable Replacement - Intermediate
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Remove the nut from the threaded end of the intermediate cable. 4. Disconnect the equalizer
from the rear park brake cables.
5. Disconnect the intermediate cable from the front cable. 6. Remove the intermediate cable.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8933
1. Install the intermediate cable. 2. Connect the intermediate cable to the front cable. 3. Connect
the equalizer to the rear park brake cables.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the nut to the threaded end of the intermediate cable.
Tighten the nut to 3.5 Nm (31 inch lbs.).
5. Remove the safety stands. 6. Lower the vehicle. 7. Adjust the park brake system.
Front
Park Brake Cable Replacement - Front
Removal Procedure
1. Release the park brake.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8934
2. Remove the park brake pedal. 3. Roll the carpet back to access cable grommet. 4. Raise and
support the vehicle. Refer to Vehicle Lifting. 5. Disengage the grommet and the cable from the floor
pan.
6. Disconnect the front cable from the intermediate cable. 7. Remove the cable from the body
mount by depressing the retaining tabs. 8. Remove the cable.
Installation Procedure
1. Install the cable. 2. Snap the retainer tabs into the body mount. 3. Connect the front cable to the
intermediate cable. 4. Route the cable in through the floor pan and engage the grommet. 5.
Remove the safety stands. 6. Lower the vehicle. 7. Roll the carpet into place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8935
8. Install the park brake pedal. 9. Adjust the park brake system.
Left Rear (Without RPO NYS)
Park Brake Cable Replacement - Left Rear (without RPO NYS)
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Relieve the tension on the park brake cables by loosening the nut at the equalizer. 4. Disconnect
the cable at the equalizer.
5. Remove the cable from the mounting bracket by depressing the locking tabs.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8936
6. Remove the cable at the shock absorber bracket by removing the bolt.
7. Remove the cable from the lever, all except 15 series utilities. 8. Remove the cable from the
backing plate by depressing the locking tabs. 9. Remove the cable.
10. Remove the cable from the lever, 15 series utilities. 11. Remove the cable from the backing
plate by depressing the locking tabs. 12. Remove the cable.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8937
1. Install the cable taking care to correctly route the cable through the guides and the body mounts.
2. Install the cable to the backing plate by pressing the cable into place until locking tabs snap into
place, 15 series utilities. 3. Install the cable to the lever.
4. Install the cable taking care to correctly route the cable through the guides and the body mounts.
5. Install the cable to the backing plate by pressing the cable into place until locking tabs snap into
place, all except 15 series utilities. 6. Install the cable to the lever.
Notice: Refer to Fastener Notice in Service Precautions.
7. Install the cable at the shock absorber bracket and install the bolt.
Tighten the bolt to 25 Nm (18 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8938
8. Install the cable to the mounting bracket until the locking tabs snap into place.
9. Connect cable end to the equalizer.
10. Tighten the nut to the intermediate cable at the equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
11. Remove the safety stands. 12. Lower the vehicle. 13. Adjust the park brake cable.
Right Rear (Without/RPO NYS)
Park Brake Cable Replacement - Right Rear (without/RPO NYS)
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Relieve the tension on the cable by loosening the nut at the equalizer. 4. Disconnect the cable
from the equalizer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8939
5. Remove the bolt from the rear axle clip. 6. Remove the cable from the differential clip.
7. Remove the cable from the mounting bracket by depressing the locking tabs.
8. Remove the cable from the left and right side cable guides, 15 series utilities. 9. Remove the
cable from the track bar clips.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8940
10. Remove the cable from the lever, all except 15 series utilities. 11. Remove the cable from the
backing plate by depressing the locking tabs. 12. Remove the cable from the retaining bracket. 13.
Remove the cable.
14. Remove the cable from the lever, 15 series utilities. 15. Remove the cable from the backing
plate by depressing the locking tabs. 16. Remove the cable from the retaining bracket. 17. Remove
the cable.
Installation Procedure
1. Install the cable taking care to correctly route the cable through the guides and the body mounts.
2. Install the cable to the backing plate by pressing the cable into place until locking tabs snap into
place, 15 series utilities. 3. Attach the cable to the lever.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8941
4. Install the cable taking care to correctly route the cable through the guides and the body mounts.
5. Install the cable to the backing plate by pressing the cable into place until locking tabs snap into
place, all except 15 series utilities. 6. Attach the cable to the lever.
7. Install the cable to the track bar and secure with the clips. Verify that the clips are installed
between the locators on the track bar, 15 series utilities. 8. Install the cable to the right and left side
guides.
9. Install the cable to the mounting bracket until the locking tabs snap into place.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8942
10. Bolt the cable to the differential clips.
Tighten the bolt to 25 Nm (18 ft. lbs.).
Important: After installing the cable to the rear axle holding clip, verify that clip is securely retaining
the cable. If not, crimp the clip by hand taking care not to pinch or kink the cable.
11. Install the cable to the differential clip.
12. Connect the cable to the equalizer. 13. Tighten the nut to the intermediate cable at the
equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
14. Remove the safety stands. 15. Lower the vehicle. 16. Adjust the park brake cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8943
Parking Brake Cable: Service and Repair Park Brake Cable Guide Replacement
Park Brake Cable Guide Replacement
Removal Procedure
1. Release the parking brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Remove the park brake cable guide bolt from the frame. 4. Remove the park brake cable guide.
5. Remove the park brake guide from the park brake cable.
Installation Procedure
1. Install the park brake cable guide to the park brake cable. 2. Install the park brake cable guide.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the park brake cable guide bolt to the frame.
Tighten the bolt to 12 Nm (106 inch lbs.).
4. Remove the safety stands. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8944
Parking Brake Cable: Service and Repair Park Brake Cable Mounting Bracket Replacement
Park Brake Cable Mounting Bracket Replacement
Removal Procedure
1. Release the parking brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Release the tension on the cables by loosening the nut at the equalizer. 4. Disconnect the rear
cables from the equalizer. 5. Remove the rear cables from the mounting bracket by depressing the
retaining tabs and pulling rearward.
6. Remove the cable support bracket nuts. 7. Remove the cable support bracket.
Installation Procedure
1. Install the cable support bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the cable support bracket nuts.
Tighten the support bracket nuts to 85 Nm (64 ft. lbs.).
3. Install the rear cables to the mounting bracket by inserting the cable till all the retaining tabs
snap into place. 4. Connect the rear cables to the equalizer.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8945
5. Tighten the nut to the intermediate cable at the equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
6. Remove the safety stands. 7. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Cable > Component
Information > Service and Repair > Park Brake Cable Replacement > Page 8946
Parking Brake Cable: Service and Repair Park Brake Cable Equalizer Replacement
Park Brake Cable Equalizer Replacement
Removal Procedure
1. Release the park brake. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Remove the nut from the threaded end of the intermediate cable. 4. Disconnect the equalizer
from the rear park brake cables.
Installation Procedure
1. Connect the equalizer to the rear park brake cables.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the nut to the threaded end of the intermediate cable.
Tighten the nut to 3.5 Nm (31 inch lbs.).
3. Remove the safety stands. 4. Lower the vehicle. 5. Adjust the park brake system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Lever > Component
Information > Specifications
Parking Brake Lever: Specifications
Park Brake Lever Mounting Bolts
............................................................................................................................................................
25 Nm (18 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Pedal > Component
Information > Adjustments
Parking Brake Pedal: Adjustments
Park Brake Pedal Adjustment
Important: Before you adjust the park brake, verify that the park brake shoes are adjusted to
provide a clearance of 0.6604 mm (0.026 inch).
1. Verify that the self adjuster lock-out pin has been removed, located in parking brake pedal
assembly, no image location provided.
(Editor's note: If there is no self-adjuster lockout pin found, as a possible alternative procedure,
please refer to Disabling/Enabling the Park Brake Cable Automatic Adjuster procedure under
Parking Brake Cable Adjustments.) See: Parking Brake Cable/Adjustments
2. Fully apply and release the park brake pedal 3 times.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Pedal > Component
Information > Service and Repair > Park Brake Pedal Assembly Replacement
Parking Brake Pedal: Service and Repair Park Brake Pedal Assembly Replacement
Park Brake Pedal Assembly Replacement
Removal Procedure
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and support the vehicle. Refer to Vehicle Lifting.
3. Relieve the tension from the park brake cables by loosening the nut at the equalizer. 4. Remove
the safety stands. 5. Lower the vehicle. 6. Remove the left side hinge pillar panel. 7. Disconnect the
park brake warning lamp connection.
8. Remove the MID-Bussed Electrical Center bracket. 9. Disconnect the park brake release cable
from the park brake lever.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Pedal > Component
Information > Service and Repair > Park Brake Pedal Assembly Replacement > Page 8955
10. Remove the park brake lever mounting nuts. 11. Disconnect the front park brake cable from the
park brake lever. 12. Remove the park brake lever.
Installation Procedure
1. Connect the front park brake cable to the park brake lever. 2. Install the park brake lever. 3.
Install the MID-Bussed Electrical Center bracket.
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the park brake lever mounting nuts.
Tighten the nuts to 25 Nm (18 ft. lbs.).
5. Raise the vehicle.
6. Support the vehicle with safety stands. 7. Tighten the nut to the intermediate cable at the
equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Pedal > Component
Information > Service and Repair > Park Brake Pedal Assembly Replacement > Page 8956
8. Remove the safety stands. 9. Lower the vehicle.
10. Connect the park brake release cable to the park brake lever. 11. Connect the park brake
warning lamp connector. 12. Install the left side hinge pillar panel. 13. Install the left side kick panel.
14. Connect the negative battery cable.
Tighten the negative battery cable bolt to 17 Nm (13 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Pedal > Component
Information > Service and Repair > Park Brake Pedal Assembly Replacement > Page 8957
Parking Brake Pedal: Service and Repair Park Brake Release Handle Assembly Replacement
Park Brake Release Handle Assembly Replacement
Removal Procedure
1. Remove the park brake release lever mounting bolt. 2. Remove the park brake release lever
handle from the knee bolster.
Installation Procedure
1. Install the park brake release lever handle to the knee bolster.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the park brake release lever mounting bolt.
Tighten to 25 Nm (18 ft. lbs.).
3. Connect the park brake release cable to the lever.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle
Parking Brake Shoe: Customer Interest Brakes - Scraping Noises From Rear of Vehicle
File In Section: 05 - Brakes
Bulletin No.: 02-05-26-002A
Date: February, 2003
TECHNICAL
Subject: Scraping Noise From Rear Of Vehicle (Replace Parking Brake Shoe Kit and Clean Drum
In Hat Rotor)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 1999-2003 Chevrolet Silverado 1500 Series
Pickups 2000-2003 Chevrolet Suburban, Tahoe 1500 Series Models 2002-2003 Chevrolet
Avalanche 1500 Series Models 1999-2003 GMC Sierra 1500 Series Pickups 2000-2003 GMC
Yukon, Yukon XL 1500 Series Models
This bulletin is being revised to add Suburban and Yukon XL models. Please discard Corporate
Bulletin Number 02-05-26-002 (Section 05 - Brakes).
Condition
Some customers may comment on a scraping noise from the rear of the vehicle while driving. The
noise may be intermittent.
Cause
Condition may due to the parking brake shoe contacting the drum in hat rotor without the parking
brake being applied, causing premature wear on the shoe lining.
Correction
Replace the parking brake shoe and install a new designed spring clip retainer. Follow the service
procedure below to correct this condition.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Information (SI Document ID # 639546).
2. Remove the tire and the wheel. Refer to Tire and Wheel Removal and Installation in the Tires
and Wheels sub-section of the Service Information (SI Document ID # 656965).
3. Relieve the tension on the park brake cables by loosening the nut at the equalizer.
4. Mark the relationship of the rotor to the hub.
5. Remove the brake caliper bracket mounting bolts.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
it's mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
6. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy
mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the
caliper.
7. Remove the rotor retaining push nuts from the wheel studs (if applicable).
Notice:
DO NOT use a hammer to remove the rotor from the hub; it may cause damage to the rotor.
Important:
The rotor may not be easily removed from the hub due to a rust build up on the outside edge of the
drum and hat portion of the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle > Page 8966
8. Remove the rotor from the hub. If the rotor cannot be removed from the hub by pulling on the
rotor, use J 46277 rotor removal tool.
Notice:
Place J 46277 between the rotor surfaces in the vent section of the rotor. DO NOT place J 46277
on the back side of the rotor surface, it may damage the rotor surface.
9. Using removal tool J 46277 on slide hammer J 6125B, remove the rotor by placing removal tool
J 46277 in the vent section of the rotor at the twelve, three, six and nine o'clock positions, not
necessarily in that order.
10. Clean the rust ridge from the drum portion of the rotor using a grinding stone and rotor
resurfacing kit J 41013.
11. Remove the spring clip bolt (3) and retainer (2) and discard.
Important:
Minimum thickness of the parking brake shoe lining in any given spot is 1.5 mm (0.06 in).
12. Measure the parking brake shoe thickness in multiple spots. Replace the parking brake shoe if
the thickness is less than 1.5 mm (0.06 in). Continue with Step 14.
13. If the parking brake shoe lining is greater than 1.5 mm (0.06 in), continue with Step 19.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle > Page 8967
14. Rotate the parking brake shoe (1) out from the bottom and pull it out of the adjuster. Discard
the shoe.
15. Remove the park brake shoe assembly from the vehicle by placing one of the open ends of the
shoe over the axle flange and rotate the shoe until it has cleared the flange.
16. Turn the adjustment screw (1) to the fully home position in the notched adjustment nut.
17. Install the new park brake shoe assembly (1) from the parking brake shoe kit, P/N 88982875, to
the vehicle by placing one of the open ends of the shoe over the axle flange and rotating the shoe
until it is behind the flange.
18. Slide the shoe into the adjuster and position the shoe to the backing plate. Install the retaining
spring clip (2) and bolt (3) from the parking brake shoe kit, P/N 88982875. If using parking brake
service kit 88982875, SKIP Step 19.
19. Replace the retaining spring clip (2) and bolt (3) from the parking brake retaining spring clip kit,
P/N 88982879.
Tighten Tighten the bolt (3) to 5 N.m (44 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle > Page 8968
20. Set the J 21177-A so that it contacts the inside diameter of the rotor.
21. Position the J 21177-A over the shoe and the lining at the widest point.
Important:
^ The parking brake adjustment screw threads should not exceed 5 mm (0.2 in) of exposed thread.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle > Page 8969
^ The clearance between the park brake shoe and the rotor is 0.6604 mm (0.026 in).
22. The parking brake adjustment screw threads should not exceed 5 mm (0.2 inch) of exposed
thread.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange with the J 42450 hub cleaning kit.
Failure to do this may result in increased lateral runout of the rotor and brake pulsation.
23. Use the J 42450-A to clean all rust and contaminants from the mating surface of the hub flange.
24. Use the J 41013 to clean all rust and contaminants from the inside diameter of the hat section
of the brake rotor to prevent any foreign material from getting between the brake rotor and the hub
flange.
25. Align the mark on the rotor with the mark on the hub and install the rotor by slowly turning the
rotor while pushing the rotor towards the axle.
26. Install the caliper and the bracket as an assembly to the vehicle.
27. Perform the following procedure before installing the caliper bracket mounting bolts.
^ Remove all traces of the original adhesive.
^ Clean the threads of the bolt with brake parts cleaner, P/N 12346139 (Canadian P/N 10953463),
and allow to dry.
^ Apply threadlocker, GM P/N 12345493 (Canadian P/N 10953488), or Red LOCTITE(TM) # 272,
to the threads of the bolt.
Notice:
Use the correct fastener in the correct location. Replacement fasteners must be the correct part
number for that application. Fasteners requiring replacement or fasteners requiring the use of
thread locking compound or sealant are identified in the service procedure. Do not use paints,
lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These
coatings affect fastener torque and joint clamping force and may damage the fastener. Use the
correct tightening sequence and specifications when installing fasteners in order to avoid damage
to parts and systems.
28. Install the caliper bracket mounting bolts.
Tighten Tighten the brake caliper bracket mounting bolts to 175 N.m (129 lb ft).
29. Repeat this procedure on the other side of the vehicle.
30. Tighten the nut to the intermediate cable at the equalizer.
Tighten Tighten the nut to 3.5 N.m (31 lb in).
31. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in the
Tires and Wheels sub-section of the Service Information (SI Document ID # 656965).
32. Lower the vehicle.
33. Verify that the self adjuster lock-out pin has been removed.
34. Fully apply and release the park brake pedal three times.
Parts Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Customer Interest: > 02-05-26-002A > Feb > 03 > Brakes - Scraping Noises
From Rear of Vehicle > Page 8970
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan
> 05 > Brakes - Park Brake Shoe Retaining Clip Kit
Parking Brake Shoe: All Technical Service Bulletins Brakes - Park Brake Shoe Retaining Clip Kit
Bulletin No.: 02-05-26-001C
Date: January 19, 2005
INFORMATION
Subject: Rear Parking Brake Shoe Retaining Spring Clip Service Kit for Drum-in-Hat (DIH)
Equipped Vehicles
Models: 2004-2005 Buick Rainier 2002-2005 Cadillac Escalade Models 2002-2005 Chevrolet
Avalanche 1998-2005 Chevrolet Blazer 1999-2005 Chevrolet Silverado Models 2000-2005
Chevrolet Suburban, Tahoe 2002-2005 Chevrolet SSR, TrailBlazer Models 2003-2005 Chevrolet
Astro, Express 1998-2005 GMC Jimmy 1999-2005 GMC Sierra Models 2000-2005 GMC Yukon
Models 2002-2005 GMC Envoy Models 2003-2005 GMC Safari, Savana 1998-2004 Oldsmobile
Bravada
This Bulletin ONLY applies to 1500 series vehicles with four wheel disc brakes.
Supercede:
This bulletin is being revised to include additional models and clarify parts usage information.
Please discard Corporate Bulletin Number 02-05-26-001B (Section 05 - Brakes).
A rear parking brake retaining spring clip kit has been released for service. This kit consists of two
parking brake hold down spring clips (2) and bolts (3).
Note:
Use J 46277 Rotor Removal Tool with J 6125-B Slide Hammer to remove the rotor from the
vehicle. Place J 46277 between the rotor surfaces in the vent section of the rotor. DO NOT place J
46277 on the back side of the rotor surface, it may damage the rotor surface.
During rear brake rotor removal, it is possible to damage the parking brake shoe retaining spring
clip. Order this new kit when replacement of the clips is required but the parking brake shoes do
not require replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan
> 05 > Brakes - Park Brake Shoe Retaining Clip Kit > Page 8976
Important:
The spring clip kits mentioned in this bulletin do not address any parking brake concerns. Refer to
the Parking Brakes sub-section of the Service Manual for any diagnostic information.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
When removal of the rear brake rotors results in damage to the spring clips on vehicles under
warranty, use the labor operation shown in conjunction with one of the kit part numbers listed
above.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan
> 05 > Brakes - Park Brake Shoe Retaining Clip Kit > Page 8977
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle
Parking Brake Shoe: All Technical Service Bulletins Brakes - Scraping Noises From Rear of
Vehicle
File In Section: 05 - Brakes
Bulletin No.: 02-05-26-002A
Date: February, 2003
TECHNICAL
Subject: Scraping Noise From Rear Of Vehicle (Replace Parking Brake Shoe Kit and Clean Drum
In Hat Rotor)
Models: 2002-2003 Cadillac Escalade, Escalade EXT 1999-2003 Chevrolet Silverado 1500 Series
Pickups 2000-2003 Chevrolet Suburban, Tahoe 1500 Series Models 2002-2003 Chevrolet
Avalanche 1500 Series Models 1999-2003 GMC Sierra 1500 Series Pickups 2000-2003 GMC
Yukon, Yukon XL 1500 Series Models
This bulletin is being revised to add Suburban and Yukon XL models. Please discard Corporate
Bulletin Number 02-05-26-002 (Section 05 - Brakes).
Condition
Some customers may comment on a scraping noise from the rear of the vehicle while driving. The
noise may be intermittent.
Cause
Condition may due to the parking brake shoe contacting the drum in hat rotor without the parking
brake being applied, causing premature wear on the shoe lining.
Correction
Replace the parking brake shoe and install a new designed spring clip retainer. Follow the service
procedure below to correct this condition.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Information (SI Document ID # 639546).
2. Remove the tire and the wheel. Refer to Tire and Wheel Removal and Installation in the Tires
and Wheels sub-section of the Service Information (SI Document ID # 656965).
3. Relieve the tension on the park brake cables by loosening the nut at the equalizer.
4. Mark the relationship of the rotor to the hub.
5. Remove the brake caliper bracket mounting bolts.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
it's mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
6. Remove the brake caliper and brake caliper bracket as an assembly and support with heavy
mechanic's wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the
caliper.
7. Remove the rotor retaining push nuts from the wheel studs (if applicable).
Notice:
DO NOT use a hammer to remove the rotor from the hub; it may cause damage to the rotor.
Important:
The rotor may not be easily removed from the hub due to a rust build up on the outside edge of the
drum and hat portion of the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle > Page 8982
8. Remove the rotor from the hub. If the rotor cannot be removed from the hub by pulling on the
rotor, use J 46277 rotor removal tool.
Notice:
Place J 46277 between the rotor surfaces in the vent section of the rotor. DO NOT place J 46277
on the back side of the rotor surface, it may damage the rotor surface.
9. Using removal tool J 46277 on slide hammer J 6125B, remove the rotor by placing removal tool
J 46277 in the vent section of the rotor at the twelve, three, six and nine o'clock positions, not
necessarily in that order.
10. Clean the rust ridge from the drum portion of the rotor using a grinding stone and rotor
resurfacing kit J 41013.
11. Remove the spring clip bolt (3) and retainer (2) and discard.
Important:
Minimum thickness of the parking brake shoe lining in any given spot is 1.5 mm (0.06 in).
12. Measure the parking brake shoe thickness in multiple spots. Replace the parking brake shoe if
the thickness is less than 1.5 mm (0.06 in). Continue with Step 14.
13. If the parking brake shoe lining is greater than 1.5 mm (0.06 in), continue with Step 19.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle > Page 8983
14. Rotate the parking brake shoe (1) out from the bottom and pull it out of the adjuster. Discard
the shoe.
15. Remove the park brake shoe assembly from the vehicle by placing one of the open ends of the
shoe over the axle flange and rotate the shoe until it has cleared the flange.
16. Turn the adjustment screw (1) to the fully home position in the notched adjustment nut.
17. Install the new park brake shoe assembly (1) from the parking brake shoe kit, P/N 88982875, to
the vehicle by placing one of the open ends of the shoe over the axle flange and rotating the shoe
until it is behind the flange.
18. Slide the shoe into the adjuster and position the shoe to the backing plate. Install the retaining
spring clip (2) and bolt (3) from the parking brake shoe kit, P/N 88982875. If using parking brake
service kit 88982875, SKIP Step 19.
19. Replace the retaining spring clip (2) and bolt (3) from the parking brake retaining spring clip kit,
P/N 88982879.
Tighten Tighten the bolt (3) to 5 N.m (44 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle > Page 8984
20. Set the J 21177-A so that it contacts the inside diameter of the rotor.
21. Position the J 21177-A over the shoe and the lining at the widest point.
Important:
^ The parking brake adjustment screw threads should not exceed 5 mm (0.2 in) of exposed thread.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle > Page 8985
^ The clearance between the park brake shoe and the rotor is 0.6604 mm (0.026 in).
22. The parking brake adjustment screw threads should not exceed 5 mm (0.2 inch) of exposed
thread.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange with the J 42450 hub cleaning kit.
Failure to do this may result in increased lateral runout of the rotor and brake pulsation.
23. Use the J 42450-A to clean all rust and contaminants from the mating surface of the hub flange.
24. Use the J 41013 to clean all rust and contaminants from the inside diameter of the hat section
of the brake rotor to prevent any foreign material from getting between the brake rotor and the hub
flange.
25. Align the mark on the rotor with the mark on the hub and install the rotor by slowly turning the
rotor while pushing the rotor towards the axle.
26. Install the caliper and the bracket as an assembly to the vehicle.
27. Perform the following procedure before installing the caliper bracket mounting bolts.
^ Remove all traces of the original adhesive.
^ Clean the threads of the bolt with brake parts cleaner, P/N 12346139 (Canadian P/N 10953463),
and allow to dry.
^ Apply threadlocker, GM P/N 12345493 (Canadian P/N 10953488), or Red LOCTITE(TM) # 272,
to the threads of the bolt.
Notice:
Use the correct fastener in the correct location. Replacement fasteners must be the correct part
number for that application. Fasteners requiring replacement or fasteners requiring the use of
thread locking compound or sealant are identified in the service procedure. Do not use paints,
lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These
coatings affect fastener torque and joint clamping force and may damage the fastener. Use the
correct tightening sequence and specifications when installing fasteners in order to avoid damage
to parts and systems.
28. Install the caliper bracket mounting bolts.
Tighten Tighten the brake caliper bracket mounting bolts to 175 N.m (129 lb ft).
29. Repeat this procedure on the other side of the vehicle.
30. Tighten the nut to the intermediate cable at the equalizer.
Tighten Tighten the nut to 3.5 N.m (31 lb in).
31. Install the tire and wheel assembly. Refer to Tire and Wheel Removal and Installation in the
Tires and Wheels sub-section of the Service Information (SI Document ID # 656965).
32. Lower the vehicle.
33. Verify that the self adjuster lock-out pin has been removed.
34. Fully apply and release the park brake pedal three times.
Parts Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Parking Brake Shoe: > 02-05-26-002A > Feb
> 03 > Brakes - Scraping Noises From Rear of Vehicle > Page 8986
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan > 05
> Brakes - Park Brake Shoe Retaining Clip Kit
Parking Brake Shoe: All Technical Service Bulletins Brakes - Park Brake Shoe Retaining Clip Kit
Bulletin No.: 02-05-26-001C
Date: January 19, 2005
INFORMATION
Subject: Rear Parking Brake Shoe Retaining Spring Clip Service Kit for Drum-in-Hat (DIH)
Equipped Vehicles
Models: 2004-2005 Buick Rainier 2002-2005 Cadillac Escalade Models 2002-2005 Chevrolet
Avalanche 1998-2005 Chevrolet Blazer 1999-2005 Chevrolet Silverado Models 2000-2005
Chevrolet Suburban, Tahoe 2002-2005 Chevrolet SSR, TrailBlazer Models 2003-2005 Chevrolet
Astro, Express 1998-2005 GMC Jimmy 1999-2005 GMC Sierra Models 2000-2005 GMC Yukon
Models 2002-2005 GMC Envoy Models 2003-2005 GMC Safari, Savana 1998-2004 Oldsmobile
Bravada
This Bulletin ONLY applies to 1500 series vehicles with four wheel disc brakes.
Supercede:
This bulletin is being revised to include additional models and clarify parts usage information.
Please discard Corporate Bulletin Number 02-05-26-001B (Section 05 - Brakes).
A rear parking brake retaining spring clip kit has been released for service. This kit consists of two
parking brake hold down spring clips (2) and bolts (3).
Note:
Use J 46277 Rotor Removal Tool with J 6125-B Slide Hammer to remove the rotor from the
vehicle. Place J 46277 between the rotor surfaces in the vent section of the rotor. DO NOT place J
46277 on the back side of the rotor surface, it may damage the rotor surface.
During rear brake rotor removal, it is possible to damage the parking brake shoe retaining spring
clip. Order this new kit when replacement of the clips is required but the parking brake shoes do
not require replacement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan > 05
> Brakes - Park Brake Shoe Retaining Clip Kit > Page 8992
Important:
The spring clip kits mentioned in this bulletin do not address any parking brake concerns. Refer to
the Parking Brakes sub-section of the Service Manual for any diagnostic information.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
When removal of the rear brake rotors results in damage to the spring clips on vehicles under
warranty, use the labor operation shown in conjunction with one of the kit part numbers listed
above.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Parking Brake Shoe: > 02-05-26-001C > Jan > 05
> Brakes - Park Brake Shoe Retaining Clip Kit > Page 8993
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Page 8994
Parking Brake Shoe: Service and Repair
Park Brake Shoe Replacement (without RPO NYS)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and the wheel. 3.
Relieve the tension on the park brake cables by loosening the nut at the equalizer. 4. Remove the
park brake cable from the park brake actuator lever. 5. Remove the rotor.
6. Turn the adjustment screw (1) to the fully home position in the notched adjustment nut. 7.
Remove the park brake shoe assembly from the backing plate by removing the tips from the slots
and sliding the shoe (2) towards the retaining
spring (3) until the shoe disengages from the spring.
8. Remove the park brake shoe assembly from the vehicle by placing one of the open ends of the
shoe over the axle flange and rotating the shoe until
it has cleared the flange.
Installation Procedure
1. Clean the debris and the dust from the park brake components using a clean shop cloth.
2. Align the slots in both the adjusting screw (1) and tappet to be parallel with the backing plate
face. 3. Install the park brake shoe assembly to the vehicle by placing one of the open ends of the
shoe (2) over the axle flange and rotating the shoe until it
is behind the flange.
4. Position the park brake shoe (2) on the inboard side of the actuator. 5. Slide the park brake shoe
(2) into position and seat into the retaining spring (3). 6. Inspect the shoe assembly position. The
shoe must be central on the backing plate with both tips located in the slots. 7. Adjust the park
brake shoe. 8. Install the rotor. 9. Install the park brake cable to the park brake actuator lever.
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Shoe > Component
Information > Technical Service Bulletins > Page 8995
10. Tighten the nut to the intermediate cable at the equalizer.
Tighten the nut to 3.5 Nm (31 inch lbs.).
11. install the tire and wheel. 12. Remove the safety stands. 13. Lower the vehicle. 14. Adjust park
brake cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Warning Switch >
Component Information > Specifications
Parking Brake Warning Switch: Specifications
Park Brake Warning Lamp Switch Bolt
.................................................................................................................................................. 3 Nm
(25 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Warning Switch >
Component Information > Specifications > Page 8999
Parking Brake Warning Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Parking Brake System > Parking Brake Warning Switch >
Component Information > Specifications > Page 9000
Parking Brake Warning Switch: Service and Repair
Park Brake Warning Lamp Switch Replacement
Removal Procedure
1. Remove the body wiring harness junction block but do not disconnect the harness.
2. Remove the park brake warning lamp switch mounting bolt. 3. Remove the park brake warning
lamp switch.
Installation Procedure
1. Install the park brake warning lamp switch.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the park brake lamp switch mounting bolt.
Tighten the bolt to 3 Nm (25 inch lbs.).
3. Install the body wiring harness junction block.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Brake Booster > Component
Information > Specifications
Hydraulic Brake Booster: Specifications
Power Brake Booster Nuts-Hydraulic
...................................................................................................................................................... 36
Nm (27 ft. lbs.) Hydraulic Power Assist ...............................................................................................
.............................................................................. 90 mm (3.54 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Brake Booster > Component
Information > Specifications > Page 9005
Hydraulic Brake Booster: Service and Repair
Hydraulic Brake Booster Replacement
Notice: Hydraulic brake systems use two distinct and incompatible fluids. Power steering fluid is
used in the hydraulic brake booster system. Brake fluid is used in the master cylinder and brake
pipes. Use extreme care when selecting brake system fluids, or seal damage can result.
Removal Procedure
1. Apply the park brake and block the wheels. 2. Disconnect the inlet hose, the steering gear, and
the hoses from the booster assembly. 3. Remove the master cylinder. 4. Remove the stop lamp
switch.
5. Remove the 4 booster to bulkhead nuts. 6. Remove the booster assembly. 7. Remove the
gasket.
Installation Procedure
1. Install the gasket. 2. Install the booster assembly.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the 4 booster to bulkhead nuts.
Tighten the nuts to 36 Nm (26 ft. lbs.).
4. Install the stop lamp switch. 5. Install the master cylinder. 6. Connect the return hose, the
steering gear, and the inlet hoses. 7. Bleed the hydraulic booster system. 8. Release the park
brake and unblock the wheels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Fluid Accumulator >
Component Information > Specifications
Hydraulic Fluid Accumulator: Specifications
Pressure Accumulator Switch (JL4)
........................................................................................................................................................ 3
Nm (30 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Fluid Accumulator >
Component Information > Specifications > Page 9009
Hydraulic Fluid Accumulator: Service and Repair
Hydraulic Brake Booster Accumulator Replacement
Tools Required ^
J26889 Accumulator Piston Compressor
Removal Procedure
Caution: The accumulator contains compressed gas. Always use the proper tools and follow the
recommended procedures or persona Injury may result. Do not apply heat to accumulator. Do not
attempt to repair an Inoperative accumulator. Always replace an inoperative accumulator with a
new one. Dispose of an inoperative accumulator by drilling a 1.5 mm (1/16 inch) diameter hole
through the end of the accumulator can, opposite the O-ring.
Caution: Push rod removal is not recommended. Improper staking of the push rod to the
Hydroboost reaction piston can result in a loss of brakes. If the rod or seals require service, the
entire unit must be replaced.
1. Apply the park brake and block the wheels. 2. Depress brake pedal at least 10 times in order to
relieve pressure in the accumulator. 3. Remove the master cylinder from the hydraulic booster.
4. Place the J26889 over the end of the accumulator. 5. Install the nut on the stud. 6. Depress the
accumulator with a C-clamp. If the accumulator does not move with moderate pressure, remove
the C-clamp and depress the brake
pedal ten times in order to relieve pressure in the accumulator.
7. Rotate the retaining ring (2) until either end of the ring is under the access hole (1). 8. Depress
and hold the retaining ring (2) with a small tool inserted into the access hole (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Fluid Accumulator >
Component Information > Specifications > Page 9010
9. Remove the accumulator retainer ring (1) using a small hook shaped tool.
10. Release the C-clamp. 11. Remove the nut from the stud.
12. Remove the J26889.
13. Remove the accumulator (2) and the O-ring seal (3)
Installation Procedure
1. Lubricate all of the seals and the metal friction points with power steering fluid.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Fluid Accumulator >
Component Information > Specifications > Page 9011
2. Install the accumulator (2) and the O-ring seal (3).
3. Place the J26889 over the end of the accumulator. 4. Install the nut on the stud. 5. Depress the
accumulator with a C-clamp.
6. Install the accumulator retainer ring (1). 7. Release the C-clamp. 8. Remove the nut from the
stud.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Hydraulic Fluid Accumulator >
Component Information > Specifications > Page 9012
9. Remove the J26889.
10. Install the master cylinder to the hydraulic booster. 11. Release the park brake and unblock the
wheels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster > Component
Information > Specifications
Vacuum Brake Booster: Specifications
Power Brake Booster Nuts-Vacuum
......................................................................................................................................................... 36
Nm (27 ft. lbs.) Vacuum Power Assist .................................................................................................
.............................................................................. 65 mm (2.56 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster > Component
Information > Specifications > Page 9016
Vacuum Brake Booster: Service and Repair
Vacuum Brake Booster Replacement
Removal Procedure
1. Apply the park brake and block the wheels. 2. Remove the brake master cylinder.
3. Remove the vacuum hose from the brake booster check valve.
4. Remove the pushrod retaining clip (4) from the brake pedal stud (1). 5. Remove the stop lamp
switch (2) and the pushrod (3) from the brake pedal stud (1).
6. Remove the 4 vacuum booster mounting nuts. 7. Remove the vacuum booster.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster > Component
Information > Specifications > Page 9017
8. Remove the gasket from the booster and discard.
Installation Procedure
1. Install the gasket to the booster. 2. Install the vacuum booster.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the 4 vacuum booster mounting nuts.
Tighten the nuts to 36 Nm (27 ft. lbs.).
4. Install the pushrod (3) and the stop lamp switch (2) to the brake pedal stud (1). 5. Install the
pushrod retaining clip (4) to the brake pedal stud (1). 6. Install the vacuum hose to the brake
booster check valve.
7. Install the master cylinder.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster > Component
Information > Specifications > Page 9018
8. Release the park brake and unblock the wheels.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster Check Valve >
Component Information > Service and Repair
Vacuum Brake Booster Check Valve: Service and Repair
Vacuum Brake Booster Check Valve and/or Hose Replacement
Removal Procedure
1. Remove the vacuum brake booster check valve from the vacuum brake booster. 2. Remove the
vacuum brake booster hose clamp at the check valve. 3. Remove the vacuum brake booster check
valve from the hose. 4. Remove the manifold sight shield-4.8L, 5.3L, 6.0L. 5. Disconnect the
vacuum brake booster hose at the engine-4.8L, 5.3L, 6.0L.
6. Disconnect the vacuum brake booster hose at the engine 4.3L. 7. Remove the vacuum brake
booster hose from the vehicle.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Power Brake Assist > Vacuum Brake Booster Check Valve >
Component Information > Service and Repair > Page 9022
1. Connect the vacuum brake booster hose at the engine 4.8L, 5.3L, 6.0L.
2. Connect the vacuum brake booster hose at the engine - 4.3L. 3. Install the manifold sight shield 4.8L, 5.3L, 6.0L. 4. Install the vacuum brake booster check valve to the hose. 5. Install the vacuum
brake booster hose clamp to the check valve. 6. Install the vacuum brake booster check valve to
the vacuum brake booster.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest for Electronic
Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Electronic Brake Control Module: Customer Interest Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > Customer Interest for Electronic
Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page
9032
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins
for Electronic Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041
Set
Electronic Brake Control Module: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > All Technical Service Bulletins
for Electronic Brake Control Module: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041
Set > Page 9038
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > Page 9039
Electronic Brake Control Module: Specifications
EBCM to BPMV Torx Bolts ..................................................................................................................
................................................. 5 Nm (39 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Technical Service Bulletins > Page 9040
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9043
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9044
Electronic Brake Control Module: Diagrams C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9045
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9046
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9047
Electronic Brake Control Module: Diagrams
C2 - W/O VSES
Electronic Brake Control Module (EBCM) - C2 - w/o VSES
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9048
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9049
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9050
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Diagrams > C1 > Page 9051
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
Electronic Brake Control Module (EBCM) Replacement (w/o JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the electrical
connectors from the EBCM. 5. Loosen or remove 3 bolts (4) securing the EHCU mounting bracket
(3) to the frame rail (5).
6. Gently move the EHCU down enough to remove the four mounting screws that fasten the
EBCM(2) to the BPMV(1). 7. Remove the EBCM (2) from the BPMV (1). Removal may require a
light amount of force. 8. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
Important: Do not reuse the old mounting screws. Always install new mounting screws with the new
EBCM.
Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
> Page 9054
1. Install the EBCM (2) on to the BPMV(1).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
3. Install or tighten three EHCU bracket mounting bolts.
Tighten the EHCU bracket mounting bolts to 25 Nm (18 ft. lbs.).
4. Connect the electrical connectors to the EBCM. 5. Lower the vehicle. 6. Connect the negative
battery cable. 7. Revise the tire calibration using the Scan Tool Tire Size Calibration function. 8.
Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
> Page 9055
Electronic Brake Control Module: Service and Repair Electronic Brake Control Module (EBCM)
(W/JL4)
Electronic Brake Control Module (EBCM) Replacement (w/ JL4)
Removal Procedure
Important: After installation, calibrate the new EBCM to the tire size that is appropriate to the
vehicle.
Caution: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Raise and suitably support the vehicle. Refer to
Vehicle Lifting.
Important: The area around the EHCU MUST be free from loose dirt to prevent contamination of
disassembled ABS components.
3. Thoroughly wash all contaminants from around the EHCU (1). 4. Disconnect the brake fluid
pressure sensor (7) and pressure accumulator switch (4) electrical connectors.
5. Remove the four mounting screws that fasten the EBCM (2) to the BPMV (1). 6. Remove the
EBCM (2) from the BPMV (1). Removal may require a light amount of force.
Important: Note the routing of the jumper harnesses for reinstallation.
7. Remove the EBCM and jumper harnesses from the vehicle. 8. Remove the jumper harnesses
from the EBCM 9. Clean the BPMV to EBCM mounting surfaces with a clean cloth.
Installation Procedure
1. Install the jumper harnesses to the EBCM. 2. Install the EBCM and jumper harnesses to the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Electronic Brake Control Module > Component Information > Service and Repair > Electronic Brake Control Module (EBCM)
> Page 9056
Important: ^
Do not reuse the old mounting screws. Always install new mounting screws with the new EBCM.
^ Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.
3. Install the EBCM (2) on to the BPMV (1).
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the four new screws in the EBCM (2).
Tighten the four screws to 5 Nm (39 inch lbs.) in an X-pattern.
5. Connect the brake fluid pressure sensor (7) and pressure accumulator switch (4) electrical
connectors. 6. Lower the vehicle. 7. Connect the negative battery cable. 8. Revise the tire
calibration using the Scan Tool Tire Size Calibration function. 9. Return to Diagnostic Starting Point
- Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Relays and Modules - Brakes and Traction Control >
Traction Control Module > Component Information > Diagrams
Inverting Driver Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Level Sensor/Switch > Component Information > Diagrams
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Level Sensor/Switch > Component Information > Diagrams > Page 9064
Brake Fluid Level Sensor/Switch: Service and Repair
Master Cylinder Fluid Level Sensor Replacement
Removal Procedure
1. Disconnect the electrical connector from the fluid level sensor.
2. Remove the fluid level sensor (1). Use a needle nose pliers in order to compress the locking tabs
at the opposite side of the master cylinder.
Installation Procedure
1. Install the fluid level sensor (1) until the locking tabs snap into place. 2. Connect the electrical
connector to the fluid level sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Specifications
Brake Fluid Pressure Sensor/Switch: Specifications
Brake Fluid Pressure Sensor (JL4)
...........................................................................................................................................................
16 Nm (12 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Locations > MPA Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Locations > MPA Switch > Page 9070
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
Brake Fluid Pressure Sensor/Switch: Service and Repair Brake Fluid Pressure Sensor
Replacement
Brake Fluid Pressure Sensor Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the alien bolt (2) from the Brake Pressure Modulator Valve (BPMV) mounting bracket
(3) located on the sensor side. 3. Raise the BPMV to access the brake fluid pressure sensor.
4. Disconnect the electrical connector from the brake fluid pressure sensor.
Important: The replacement of the old brake fluid pressure sensor must be performed quickly to
reduce the amount of fluid that is lost during the procedure.
5. Use a wrench to keep the brake fluid pressure sensor collar from turning (1).
Remove the brake fluid pressure sensor (2) from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
> Page 9073
Notice: Refer to Fastener Notice in Service Precautions.
1. Quickly install the new brake fluid pressure sensor (2) to the BPMV as soon as the old sensor
has been removed.
Use a wrench to keep the brake fluid pressure sensor collar from turning (1). Tighten the brake fluid
pressure sensor to 16 Nm (12 ft. lbs.).
2. Install the alien bolt (2) to the Brake Pressure Modulator Valve (BPMV) mounting bracket (3).
Tighten the alien bolt to 9 Nm (7 ft. lbs.).
3. Connect the electrical connector to the brake fluid pressure sensor. 4. Lower the vehicle. 5.
Check and fill the brake fluid level in the master cylinder.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
> Page 9074
Brake Fluid Pressure Sensor/Switch: Service and Repair Pressure Accumulator Switch
Replacement
Pressure Accumulator Switch Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the bolts (2) that secure the Brake Pressure Modulator Valve (BPMV) (1) to the
mounting bracket (3).
3. Disconnect the electrical connector from the pressure accumulator switch.
4. Position the BPMV to be able to remove the pressure accumulator switch. 5. Remove the
pressure accumulator switch from the BPMV.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Brake
Fluid Pressure Sensor/Switch > Component Information > Service and Repair > Brake Fluid Pressure Sensor Replacement
> Page 9075
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the pressure accumulator switch to the BPMV.
Tighten the pressure accumulator switch to 3 Nm (30 inch lbs.).
2. Connect the electrical connector to the pressure accumulator switch.
3. Install the Brake Pressure Modulator Valve (BPMV) (1) and the bolts (2) to the mounting bracket
(3).
Tighten the bolts to 9 Nm (7 ft. lbs.).
4. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Parking Brake Warning Switch > Component Information > Specifications
Parking Brake Warning Switch: Specifications
Park Brake Warning Lamp Switch Bolt
.................................................................................................................................................. 3 Nm
(25 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Parking Brake Warning Switch > Component Information > Specifications > Page 9079
Parking Brake Warning Switch
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Parking Brake Warning Switch > Component Information > Specifications > Page 9080
Parking Brake Warning Switch: Service and Repair
Park Brake Warning Lamp Switch Replacement
Removal Procedure
1. Remove the body wiring harness junction block but do not disconnect the harness.
2. Remove the park brake warning lamp switch mounting bolt. 3. Remove the park brake warning
lamp switch.
Installation Procedure
1. Install the park brake warning lamp switch.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the park brake lamp switch mounting bolt.
Tighten the bolt to 3 Nm (25 inch lbs.).
3. Install the body wiring harness junction block.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Traction Control Switch > Component Information > Locations
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Traction Control Switch > Component Information > Locations > Page 9084
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Traction Control Switch > Component Information > Service and Repair > Stabilitrak
Traction Control Switch: Service and Repair Stabilitrak
Traction Control Switch Replacement (Stabilitrak)
Removal Procedure
1. Remove Instrument Panel (IP) bezel.
2. Gently lift the retaining tabs (2) and remove the stabilitrak switch (3) from the instrument panel
(IP) assembly (1).
3. Disconnect the harness connector from the stabilitrak switch.
Installation Procedure
1. Connect the harness connector to the stabilitrak switch.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Traction Control Switch > Component Information > Service and Repair > Stabilitrak > Page 9087
2. Install the stabilitrak switch (3) into the Instrument Panel (IP) assembly (1) 3. Ensure that the
switch is secure into both retaining tabs (2). 4. Install instrument panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Traction Control Switch > Component Information > Service and Repair > Stabilitrak > Page 9088
Traction Control Switch: Service and Repair Traction Control
Traction Control Switch Replacement (Traction Control)
Removal Procedure
1. Remove instrument panel (IP) bezel.
2. Gently lift the switch retaining tabs (1) and remove the traction control switch (2) from the
Instrument Panel (IP) assembly (3). 3. Disconnect the harness connector from the traction control
switch.
Installation Procedure
1. Connect the harness connector to the traction control switch.
2. Install the traction control switch (2) into the instrument panel (IP) assembly (3), making sure that
all of the switch retaining tabs (1) are engaged. 3. Install Instrument Panel (IP) bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9097
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9098
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9099
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9100
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9101
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9102
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9103
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 05068C > Mar > 08 > Recall Possible Front Wheel Speed Sensor Corrosion > Page 9104
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > NHTSA05V379000 > Aug > 05 >
Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: Recalls Recall 05V379000: Wheel Speed Sensor Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9113
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9114
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9115
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9116
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9117
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9118
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9119
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9120
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Recalls: > 04094 > Jan > 05 > Recall - Front
Wheel Speed Sensor Corrosion > Page 9121
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May
> 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: Customer Interest Brakes - Low Speed ABS Activation/No DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Customer Interest: > 03-05-25-007D > May
> 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 9127
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 9133
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9138
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9139
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9140
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9141
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9142
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9143
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9144
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9145
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9154
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9155
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9156
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9157
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9158
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9159
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9160
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9161
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Technical Service Bulletins for Wheel
Speed Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9162
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set
Wheel Speed Sensor: All Technical Service Bulletins Brakes - Low Speed ABS Activation/No
DTC's Set
TECHNICAL
Bulletin No.: 03-05-25-007D
Date: May 01, 2009
Subject: Antilock Brake (ABS) Activation At Low Speeds (Clean Wheel Speed Sensor Mounting
Surface)
Models:
2002-2006 Cadillac Escalade, Escalade EXT 2003-2006 Cadillac Escalade ESV 1999-2006
Chevrolet Silverado 2001-2006 Chevrolet Suburban, Tahoe 2002-2006 Chevrolet Avalanche
2003-2006 Chevrolet Express 2007 Chevrolet Silverado Classic 1999-2006 GMC Sierra 2001-2006
GMC Yukon, Yukon Denali, Yukon XL, Yukon Denali XL 2003-2006 GMC Savana 2007 GMC
Sierra Classic 2003-2006 HUMMER H2
..............................................................................................................................................................
.................................................................................. Supercede: This bulletin is being revised to
add the 2007 Silverado/Sierra Classic models. Please discard Corporate Bulletin Number
03-05-25-007C (Section 05 - Brakes).
..............................................................................................................................................................
..................................................................................
Condition
Some customers may comment on ABS activation at low speeds, usually below 8 km/h (5 mph).
Upon investigation, the technician will find no DTCs set.
Cause
The cause of this condition may be an increased air gap between the wheel speed sensor and the
hub reluctor ring due to rust and debris built up on the sensor mounting surface.
Correction
Measure AC voltage and clean the wheel speed sensor mounting surfaces.
1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in the General
Information sub-section of the Service Manual. 2. Disconnect both the front wheel speed sensor
connectors at the frame and harness. 3. Place a Digital Volt Meter (DVM) across the terminals of
each wheel speed sensor connector. 4. Rotate the wheel clockwise approximately one revolution
per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's, remove the wheel speed sensor. Refer to the applicable Wheel Speed Sensor
Replacement procedure in the ABS sub-section of the Service Manual.
5. Plug the wheel speed sensor bore in order to prevent debris from falling into the hub during
service. 6. Clean the wheel speed sensor mounting surface using a wire brush, sand paper, emery
cloth, scotch brite, or other suitable material. Be sure to
thoroughly clean the wheel speed sensor surface. There should be no rust or corrosion.
7. Check the sensor head to determine if it has been warped/distorted due to the corrosion build up
or other causes. Check the mounting surface on
the sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple (minimum 3)
positions/directions. If the sensor head is distorted, replace the sensor.
8. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) to the
complete sensor mounting surface on the
bearing hub. Allow to dry for 3-5 minutes between coats. Use ONLY Rust Penetrating Lubricant,
P/N 89022217 (in Canada, P/N 89022218).
9. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a thin layer of bearing
grease to the hub surface and sensor O-ring prior
to sensor installation. Use ONLY Wheel Bearing Lubricant, P/N 01051344 (in Canada, P/N
993037).
10. Install either the original sensor or a new one in the hub. Ensure that the sensor is seated flush
against the hub. Refer to the applicable Wheel
Speed Sensor Replacement procedure in the ABS sub-section of the Service Manual.
11. Place the DVM across the sensor terminals and recheck the voltage while rotating the wheel.
The voltage should now read at least 350 ACmV's.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 03-05-25-007D > May > 09 > Brakes - Low Speed ABS Activation/No DTC's Set > Page 9168
Parts Information
Place unused material on dealer shelf for future use.
Warranty Information
For vehicles repaired under warranty, use the table above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 05068C Date: 080306
Recall - Possible Front Wheel Speed Sensor Corrosion
SAFETY
Bulletin No.: 05068C
Date: March 06, 2008
Subject: 05068C - FRONT WHEEL SPEED SENSOR CORROSION
Models: 1999-2002 CHEVROLET SILVERADO 2000-2002 CHEVROLET TAHOE, SUBURBAN
2002 CHEVROLET AVALANCHE 1999-2002 GMC SIERRA 2000-2002 GMC YUKON, YUKON XL
LOCATED IN THE SEVERE CORROSION AREAS LISTED BELOW
Supercede:
Some breakpoints in this bulletin have been revised. Additional vehicles that have moved into the
severe corrosion areas have been added. Please discard all copies of bulletin 05068B, issued April
2006.
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in the
areas shown above. These vehicles may have a condition permitting corrosion to occur between
the front hub/bearing assembly and the wheel speed sensor. If the brakes are applied while the
vehicle is traveling at a speed of greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph) the
corrosion may cause an unwanted anti-lock brake system (ABS) activation. If this condition
occurred where stopping distance is limited a crash could occur.
Correction
Dealers are to inspect clean and treat the affected area. In some cases the front wheel speed
sensor may require replacement.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9174
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9175
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra and 2000-2002 GMC Yukon, Yukon XL vehicles
located in severe corrosion areas and built within the VIN breakpoints shown.
Important:
Dealers retailers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System)
prior to beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles a Campaign Initiation Detail Report (CIDR) containing the
complete vehicle identification number customer name and address data has been prepared and
will be loaded to the GM DealerWorld (US) Recall Information. Dealers will not have a report
available if they have no involved vehicles currently assigned.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly you are urged to limit the use of this report to the follow-up
necessary to complete this recall.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required order appropriate
part from GMSPO.
Customer Reimbursement
All customer requests for reimbursement for previous repairs for the recall condition will be handled
by the Customer Assistance Center not by dealers.
Important:
(For GM US Only) Refer to the GM Service Policies and Procedures Manual, section 6.1.12, for
specific procedures regarding customer reimbursement.
Claim Information
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9176
Submit a Product Recall Claim with the information shown.
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility
The US National Traffic and Motor Vehicle Safety Act provides that each vehicle that is subject to a
recall of this type must be adequately repaired within a reasonable time after the customer has
tendered it for repair. A failure to repair within sixty days after tender of a vehicle is prima facie
evidence of failure to repair within a reasonable time. If the condition is not adequately repaired
within a reasonable time the customer may be entitled to an identical or reasonably equivalent
vehicle at no charge or to a refund of the purchase price less a reasonable allowance for
depreciation. To avoid having to provide these burdensome remedies every effort must be made to
promptly schedule an appointment with each customer and to repair their vehicle as soon as
possible. In the recall notification letters customers are told how to contact the US National
Highway Traffic Safety Administration if the recall is not completed within a reasonable time.
All unsold new vehicles in dealers possession and subject to this recall must be held and
inspected/repaired per the service procedure of this recall bulletin before customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers regardless of
mileage age of vehicle or ownership from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory and for which
there is no customer information indicated on the dealer listing are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin for your use in
contacting customers. Recall follow-up cards should not be used for this purpose since the
customer may not as yet have received the notification letter.
In summary whenever a vehicle subject to this recall enters your vehicle inventory or is in your
dealership for service in the future you must take the steps necessary to be sure the recall
correction has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9177
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
2. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
3. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire or equivalent whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9178
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinists scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
^ If the sensor mounting surface is NOT flat (1) the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2) the sensor IS to be reused. Proceed to Step 16.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9179
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed harness electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame upper control arm and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush sandpaper emery cloth scotch-brite or equivalent thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust or corrosion.
18. Using compressed air remove all debris from the bearing hub surface.
19. Using a clean shop towel clean the sensor and the 0-ring.
Important:
While the corrosion inhibitor is drying in the next step, begin performing Steps 3-20 on the opposite
side front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes) apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9180
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 N.m (13 lb ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmV's. If the reading is less
than 350 ACmV's the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated after the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
1. Remove all traces of the original adhesive patch.
2. Clean the threads of the bolt with brake parts cleaner or the equivalent and allow to dry.
3. Apply threadlocker to the threads of the bolts.
28. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles - 175 N.m (129 lb ft)
^ 2500 Series vehicles - 300 N.m (221 lb ft)
29. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 N.m (140 lb ft).
30. Complete Steps 21-30 on the opposite side front wheel speed sensor.
31. Lower the vehicle.
32. With the engine OFF gradually apply the brake pedal to approximately 2/3 of its travel distance.
33. Slowly release the brake pedal.
34. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 05068C > Mar > 08 > Recall - Possible Front Wheel Speed Sensor Corrosion > Page 9181
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > NHTSA05V379000 > Aug > 05 > Recall 05V379000: Wheel Speed Sensor Cleaning
Wheel Speed Sensor: All Technical Service Bulletins Recall 05V379000: Wheel Speed Sensor
Cleaning
MAKE/MODELS: MODEL/BUILD YEARS: Chevrolet/Avalanche 1999-2002 Chevrolet/Silverado
1999-2002 Chevrolet/Suburban 1999-2002 Chevrolet/Tahoe 1999-2002 GMC/Sierra 1999-2002
GMC/Yukon 1999-2002 GMC/Yukon XL 1999-2002 MANUFACTURER: General Motors Corp.
NHTSA CAMPAIGN ID NUMBE : 05V379000 MFG'S REPORT DATE: August 29, 2005
COMPONENT: Service Brakes, Hydraulic: Antilock
POTENTIAL NUMBER OF UNITS AFFECTED: 804000
SUMMARY: Certain pickup trucks and sport utility vehicles may experience unwanted Antilock
Brake System (ABS) activation. This condition is more likely to occur in environmentally corrosive
areas. This recall will be launched in the "SALT BELT" states of Connecticut, Illinois, Indiana,
Massachusetts, Maine, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania,
Rhode Island, Vermont and West Virginia only.
CONSEQUENCE: This can cause increased stopping distances during low-speed brake
applications, which could result in a crash.
REMEDY: Dealers are to remove the wheel speed sensor and thoroughly clean the wheel speed
sensor mounting surface on the bearing, apply rust inhibitor to the cleaned surface, grease the
mounting surface, reinstall the wheel speed sensor, and check the peak-to-peak output voltage to
ensure the wheel speed signal is within specifications. The manufacturer has not yet provided an
owner notification schedule. Owners should contact Chevrolet at 1-800-630-2438 or GMC at
1-866-996-9463.
NOTES: GM recall No. 05068. Customers can also contact The National Highway Traffic Safety
Administration's Vehicle Safety Hotline at 1-888-327-4236 (TTY 1-800-424-9153), or go to
http://www.safercar.gov.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion
Technical Service Bulletin # 04094 Date: 050125
Recall - Front Wheel Speed Sensor Corrosion
Product Safety - Front Wheel Speed Sensor Corrosion # 04094 - (Jan 25, 2005)
Models: 1999-2002 Chevrolet Silverado 2000-2002 Chevrolet Tahoe, Suburban 2002 Chevrolet
Avalanche 1999-2002 GMC Sierra 2000-2002 GMC Yukon, Yukon XL
Located in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, Prince Edward Island
Condition
General Motors has decided that a defect which relates to motor vehicle safety exists in certain
1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002 Chevrolet
Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located in Ontario,
Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island. These vehicles
may have a condition permitting corrosion to occur between the front hub/bearing assembly and
the wheel speed sensor. If the brakes are applied while the vehicle is travelling at a speed of
greater than 6 km/h (3.7 mph) but less than 16 km/h (10 mph), the corrosion may cause an
unwanted anti-lock brake system (ABS) activation. If this condition occurred where stopping
distance is limited, a crash could occur.
Correction
Dealers are to clean and treat the affected area, and in some cases, replace the front wheel speed
sensor.
Vehicles Involved
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9190
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9191
Involved are certain 1999-2002 Chevrolet Silverado, 2000-2002 Chevrolet Tahoe, Suburban, 2002
Chevrolet Avalanche, 1999-2002 GMC Sierra, 2000-2002 GMC Yukon, Yukon XL vehicles located
in Ontario, Quebec, Newfoundland, New Brunswick, Nova Scotia, and Prince Edward Island and
built within the VIN breakpoints shown.
Important:
Dealers should confirm vehicle eligibility through GMVIS (GM Vehicle Inquiry System) before
beginning recall repairs. [Not all vehicles within the above breakpoints may be involved.]
For dealers with involved vehicles, a Campaign Initiation Detail Report containing the complete
Vehicle Identification Number, customer name and address data has been prepared and is being
furnished to involved dealers. Dealers that have no involved vehicles currently assigned will not
receive a report with the recall bulletin.
The Campaign Initiation Detail Report may contain customer names and addresses obtained from
Motor Vehicle Registration Records. The use of such motor vehicle registration data for any other
purpose other than follow-up necessary to complete this recall is a violation of law in several
states/provinces/countries. Accordingly, you are urged to limit the use of this report to the follow-up
necessary to complete this program.
Parts Information
Parts required to complete this recall are to be obtained from General Motors Service Parts
Operations (GMSPO). Please refer to your "involved vehicles listing" before ordering parts. Normal
orders should be placed on a DRO = Daily Replenishment Order. In an emergency situation, parts
should be ordered on a CSO = Customer Special Order.
Note:
Very few vehicles will require front wheel speed sensor replacement; if required, order appropriate
part from GMSPO.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9192
Customer Reimbursement - For Canada
Customer requests for reimbursement of previously paid repairs to correct the condition addressed
in this bulletin are to be submitted by January 31, 2006.
All reasonable customer paid receipts should be considered for reimbursement. The amount to be
reimbursed will be limited to the amount the repair would have cost if completed by an authorized
General Motors dealer.
When a customer requests reimbursement, they must provide the following:
^ Proof of ownership at time of repair.
^ Original paid receipt confirming the amount of repair expense(s) that were not reimbursed, a
description of the repair, and the person or entity performing the repair.
^ Claims for customer reimbursement on previously paid repairs are to be submitted as required by
WINS.
Important:
Refer to the GM Service Policies and Procedures Manual, section 1.6.2, for specific procedures
regarding customer reimbursement verification.
Courtesy Transportation
The General Motors Courtesy Transportation program is intended to minimize customer
inconvenience when a vehicle requires a repair that is covered by the New Vehicle Limited
Warranty. The availability of courtesy transportation to customers whose vehicles are within the
warranty coverage period and involved in a product recall is very important in maintaining customer
satisfaction. Dealers are to ensure that these customers understand that shuttle service or some
other form of courtesy transportation is available and will be provided at no charge. Dealers should
refer to the General Motors Service Policies and Procedures Manual for Courtesy Transportation
guidelines.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9193
Claim Information
Customer Notification
General Motors will notify customers of this recall on their vehicle (see copy of customer letter
shown in this bulletin).
Dealer Recall Responsibility -- All
All unsold new vehicles in dealers' possession and subject to this recall MUST be held and
inspected/repaired per the service procedure of this recall bulletin BEFORE customers take
possession of these vehicles.
Dealers are to service all vehicles subject to this recall at no charge to customers, regardless of
mileage, age of vehicle, or ownership, from this time forward.
Customers who have recently purchased vehicles sold from your vehicle inventory, and for which
there is no customer information indicated on the dealer listing, are to be contacted by the dealer.
Arrangements are to be made to make the required correction according to the instructions
contained in this bulletin. A copy of the customer letter is shown in this bulletin. Recall follow-up
cards should not be used for this purpose, since the customer may
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9194
not as yet have received the notification letter.
In summary, whenever a vehicle subject to this recall enters your vehicle inventory, or is in your
dealership for service in the future, please take the steps necessary to be sure the recall correction
has been made before selling or releasing the vehicle.
Disclaimer
Service Procedure
The following procedure provides instructions for repairing a corrosion condition where the front
wheel speed sensor mounts on the front wheel bearing assembly.
1. Raise the vehicle on a suitable hoist and support as necessary.
2. Remove both front tires and wheels.
3. Compress the front brake caliper pistons.
A. Install a large C-clamp over the top of the caliper housing and against the back of the outboard
pad.
B. Slowly tighten the C-clamp until the pistons are pushed completely into the caliper bores.
C. Remove the C-clamp from the caliper.
Important:
It is not necessary to remove the front brake caliper from the bracket when removing the bracket in
the next step.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9195
4. Remove the two bolts that attach the front brake caliper mounting brackets to the knuckle.
Notice:
Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from
its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in
this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause
damage to the brake hose and in turn may cause a brake fluid leak.
5. Remove the brake caliper and bracket as an assembly and support it with heavy mechanic's
wire or equivalent. DO NOT disconnect the hydraulic brake flexible hose from the caliper.
6. Mark the relationship of the rotor to the bearing hub.
7. If equipped, remove the rotor retaining push nuts from the wheel studs.
8. Remove the rotor.
9. Remove the bolt (1) that attaches the wheel speed sensor to the bearing hub.
Notice:
Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a screwdriver or
other device to try to pry the sensor out of the bore. Prying will cause the sensor body to break off
in the bore.
10. Remove the wheel speed sensor from the bearing hub assembly.
Important:
The mounting surface on the sensor must be flat in the next step in order to be mounted correctly
on the bearing hub assembly. If the mounting surface on the sensor is warped or bent, the sensor
must be replaced.
11. Inspect to see if the mounting surface on the sensor is flat. Check the mounting surface on the
sensor head for flatness by placing it on the edge of a metal machinist's scale or other suitable
straight edge to measure the flatness. Check the sensor for flatness in multiple positions/directions
(minimum 3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9196
^ If the sensor mounting surface is NOT flat (1), the sensor must be replaced. Proceed to the next
step and replace the sensor.
^ If the sensor mounting surface IS flat (2), the sensor IS to be reused. Proceed to Step 16.
12. Remove the wheel speed harness mounting clips from the knuckle (4) upper control arm (3)
and frame (2).
13. Disconnect the wheel speed sensor electrical connector (1) from the vehicle wiring harness.
14. Connect the new wheel speed sensor harness electrical connector to the vehicle wiring
harness.
15. Attach the wheel speed sensor harness to the frame, upper control arm, and the knuckle.
16. Temporarily plug the wheel speed sensor hole (1) in the bearing hub to prevent debris from
entering it when you clean it.
Important:
All rust and corrosion must be removed from the wheel speed sensor mounting surfaces on the
bearing hub in the next step.
17. Using a wire brush, sandpaper, emery cloth, scotch brite, or equivalent, thoroughly clean the
wheel speed sensor mounting surface (2) on the bearing hub to remove any rust of corrosion.
18. Using compressed air, remove all debris from the bearing hub surface.
19. Using a clean shop towel, clean the sensor and the 0-ring.
Important:
While the corrosion is drying in the next step, begin performing Steps 3-20 on the opposite side
front wheel speed sensor.
20. Apply (spray) two thin coats of the specified rust penetrating lubricant (corrosion inhibitor) listed
in this bulletin, to the complete sensor mounting surface on the bearing hub. Allow to dry for 3-5
minutes between coats.
21. When the corrosion inhibitor is dry to the touch (about 10 minutes), apply a light coating of the
specified grease to the complete sensor mounting surface on the bearing hub and to the sensor
and 0-ring.
22. Remove the temporary plug from the hole in the bearing hub.
23. Install the wheel speed sensor in the bearing hub and install the bolt. Ensure that the sensor is
seated flat against the hub.
Tighten
Tighten the wheel speed sensor mounting bolt to 18 Nm (13 lb-ft).
24. Disconnect the front wheel speed sensor connector and place a digital volt meter (DVM) across
the terminals of the wheel speed sensor connector. Rotate the bearing at approximately one
revolution per second. The minimum reading should be at least 350 ACmVs. If the reading is less
than
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9197
350 ACmVs, the wheel speed sensor must be replaced. Follow Steps 12-15 for instructions on
replacing the wheel speed sensor. This step must be repeated afier the new sensor has been
installed.
Notice:
Whenever the brake rotor has been separated from the wheel bearing flange, clean any rust or
foreign material from the mating surface of the rotor and flange. Failure to do this may result in
increased lateral runout of the rotor and brake.
Important:
If the rotor was removed using the jack screw method, you must ensure that the hub flange is free
of nicks or marks caused by this procedure. Remove all raised nicks or marks before installing the
rotor.
25. Align the rotor to its original position on the hub and install the rotor.
26. Install the caliper and caliper mounting bracket assembly.
27. Perform the following procedure before installing the brake caliper bracket mounting bolts.
28. Remove all traces of the original adhesive patch.
A. Clean the threads of the bolt with brake parts cleaner, or the equivalent, and allow to dry.
B. Apply threadlocker to the threads of the bolts.
29. Install the caliper bracket mounting bolts. Tighten the brake caliper mounting bracket mounting
bolts to the specification listed below.
Tighten
^ 1500 Series vehicles -- 175 Nm (129 lb-ft)
^ 2500 Series vehicles -- 300 Nm (221 lb-ft)
30. Install the front tire and wheel assembly.
Tighten
Tighten the wheel nuts to 190 Nm (140 lb-ft).
31. Complete Steps 21-30 on the opposite side front wheel speed sensor.
32. Lower the vehicle.
33. With the engine OFF, gradually apply the brake pedal to approximately 2/3 of its travel
distance.
34. Slowly release the brake pedal.
35. Wait 15 seconds and repeat Steps 32-33 until a firm pedal is obtained. This will properly seat
the brake caliper pistons and brake pads.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > All Other Service Bulletins for Wheel Speed
Sensor: > 04094 > Jan > 05 > Recall - Front Wheel Speed Sensor Corrosion > Page 9198
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Page 9199
Wheel Speed Sensor: Specifications
Front Wheel Speed Sensor Mounting Bolt
............................................................................................................................................... 18 Nm
(13 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Technical Service Bulletins > Page 9200
Wheel Speed Sensor - RF (4WD)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Diagrams > LF
Wheel Speed Sensor (WSS) - LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Diagrams > LF > Page 9203
Wheel Speed Sensor (WSS) - RF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Diagrams > Page 9204
Wheel Speed Sensor: Service and Repair
Wheel Speed Sensor Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the brake rotor (2). 4. Remove the Wheel Speed Sensor (WSS) mounting bolt.
Notice: Carefully remove the sensor by pulling it straight out of the bore. DO NOT use a
screwdriver, or other device to pry the sensor out of the bore. Prying will cause the sensor body to
break off in the bore.
5. Remove the wheel speed sensor (5) from the hub/bearing assembly (4). 6. Remove the WSS
cable mounting clip from the knuckle. 7. Remove the WSS cable mounting clip from the upper
control arm. 8. Remove the WSS cable mounting clip from the frame attachment point. 9. Remove
the WSS cable electrical connector.
Installation Procedure
1. Install the WSS (5) into the hub/bearing assembly (4).
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the WSS mounting bolt.
Tighten the WSS mounting bolt to 18 Nm (13 ft. lbs.).
3. Install the WSS cable mounting clip to the knuckle. 4. Install the WSS cable mounting clip to the
upper control arm. 5. Install the WSS cable mounting clip to the frame attachment point. 6. Connect
the WSS cable electrical connector. 7. Install the brake rotor (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control >
Wheel Speed Sensor > Component Information > Diagrams > Page 9205
8. Install the tire and wheel. 9. Return to Diagnostic Starting Point - Antilock Brake System.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Yaw
Rate Sensor > Component Information > Specifications
Yaw Rate Sensor: Specifications
Yaw Rate Sensor/Lateral Accelerometer Nut
........................................................................................................................................ 10 Nm (89
inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Brakes and Traction Control > Sensors and Switches - Brakes and Traction Control > Yaw
Rate Sensor > Component Information > Specifications > Page 9209
Yaw Rate Sensor: Service and Repair
Yaw Rate Sensor/Lateral Accelerometer Replacement
Removal Procedure
1. Remove the front floor console bezel. 2. Disconnect the yaw rate sensor/lateral accelerometer
electrical connector.
3. Remove the 3 yaw rate sensor/lateral accelerometer nuts. 4. Remove the yaw rate sensor/lateral
accelerometer from the vehicle.
Installation Procedure
Important: Use care not to bend or distort the bracket that supports the yaw rate sensor/lateral
accelerometer.
1. Install the yaw rate sensor/lateral accelerometer to the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the 3 yaw rate sensor/lateral accelerometer nuts to the bracket.
Tighten the nuts to 10 Nm (89 inch lbs.).
3. Connect the yaw rate sensor/lateral accelerometer electrical connector. 4. Install the front floor
bezel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Sensors and Switches - Starting and Charging > Ignition Switch >
Ignition Switch Lock Cylinder > Component Information > Technical Service Bulletins > Ignition Lock Cylinder - Revised
Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations
Starter Relay: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations > Page 9221
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Relays and Modules - Starting and Charging > Starter Relay >
Component Information > Locations > Page 9222
Starter Relay: Service and Repair
REMOVAL PROCEDURE
1. Remove the underhood bussed electrical center (UBEC) cover. 2. Remove the starter motor
relay.
INSTALLATION PROCEDURE
1. Install the starter motor relay. 2. Install the underhood bussed electrical center (UBEC) cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative)
Negative: Service and Repair Battery Cable Replacement (Negative)
REMOVAL PROCEDURE
CAUTION: refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable.
2. If equipped with a 4.8L, 5.3L, or 6.OL engine, remove the battery cable bracket bolt and bracket
from the power steering pump.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9229
3. If equipped, disconnect the accessory power fuse block front wiring harness electrical connector
from the negative cable connector.
4. If equipped with a 4.8L, 5.3L, or 6.OL engine, remove the negative cable clip from positive cable
clip. 5. Raise and suitably support the vehicle with safety stands. Refer to Lifting and Jacking the
Vehicle. 6. Remove the engine wiring harness
7. If equipped with a 8.1L engine, remove the negative cable clip from the positive cable clip. 8.
Raise and suitably support the vehicle with safety stands. Refer to Lifting and JackThg the Vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9230
9. Remove the engine wiring harness ground/negative cable bolt. 10. Reposition the wiring harness
ground and negative cables.
11. Remove the forward lamp wiring harness ground/negative cable bolt. 12. Remove the negative
battery cable.
INSTALLATION PROCEDURE
1. Install the negative battery cable. 2. Position the negative cable and forward lamp wiring harness
ring terminals to the frame.
Insert the anti-rotation tab on the forward lamp wiring harness into the hole in the frame.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the forward lamp wiring harness ground/negative cable bolt.
Tighten Tighten the forward lamp wiring harness ground/negative cable bolt to 9 N.m (80 lb in).
IMPORTANT: The engine wiring harness ground is to be installed under the negative cable ground.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9231
4. If equipped with a 8.1L engine, position the wiring harness ground and negative cables. Position
the anti-rotation tab on the negative cable in the
correct location.
5. Install the engine wiring harness ground/negative cable bolt.
Tighten Tighten the engine wiring harness ground/negative cable bolt to 25 N.m (18 lb ft).
6. Lower the vehicle. 7. Install the negative cable clip to the positive cable clip.
8. If equipped with a 4.8L, 5.3L, or 6.OL engine, position the negative cable and engine wiring
harness ring terminals to the engine block.
Position the anti-rotation tab on the negative cable in the correct location.
9. Install the engine wiring harness ground/negative cable bolt.
Tighten Tighten the engine wiring harness ground/negative cable bolt to 25 N.m (18 lb ft).
10. Lower the vehicle. 11. Install the negative cable clip to the positive cable clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9232
12. If equipped, connect the accessory power fuse block front wiring harness electrical connector to
the negative cable connector.
13. Install the battery cable bracket and bolt to the power steering pump
Tighten Tighten the battery cable bracket bolt to 25 N.m (18 lb ft).
14. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9233
Negative: Service and Repair Battery Negative Cable Disconnect/Connect Procedure
Single Battery
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Turn off all the lamps and accessories. 2. Turn the ignition OFF. 3. Remove the battery ground
negative cable and bolt from the battery.
INSTALLATION PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions
IMPORTANT: Clean any existing corrosion from the battery terminal bolt flange and the battery
cable end. Install the battery ground negative cable and bolt to the battery.
Tighten Tighten the battery terminal bolt to 17 N.m (13 lb ft).
Auxiliary Battery
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9234
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Turn off all the lamps and accessories. 2. Turn the ignition OFF. 3. Remove the battery ground
negative cable and bolt from the battery.
INSTALLATION PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
IMPORTANT: Clean any existing corrosion from the battery terminal bolt flange and the battery
cable end. Install the battery ground negative cable and bolt to the battery.
Tighten Tighten the battery terminal bolt to 17 N.m (13 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9235
Negative: Service and Repair Battery Negative Cable Replacement - Auxiliary
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the auxiliary negative battery cable. 2. Remove the auxiliary battery cable clips from
the studs at the front of dasti. 3. Remove the engine sight shield.
4. If equipped with a 4.8L, 5.3L, or 6.OL engine, remove the engine wiring harness/auxiliary
negative battery cable bolt. 5. Remove the auxiliary negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9236
6. If equipped with a 8.1L engine, remove the engine wiring harness/auxiliary negative battery
cable bolt. 7. Remove the auxiliary negative battery cable.
INSTALLATION PROCEDURE
IMPORTANT: Install the auxiliary negative battery cable terminal behind the engine wiring harness
ground terminal.
1. If equipped with a 8.1L engine, install the auxiliary negative battery cable.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the engine wiring harness/auxiliary negative battery cable bolt.
Tighten Tighten the engine wiring harness/auxiliary negative battery cable bolt to 16 N.m (12 lb ft).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9237
4. If equipped with a 4.8L, 5.3L, or 6.OL engine, remove the engine wiring harness/auxiliary
negative battery cable bolt. 5. Remove the auxiliary negative battery cable.
6. If equipped with a 8.1L engine, remove the engine wiring harness/auxiliary negative battery
cable bolt. 7. Remove the auxiliary negative battery cable.
INSTALLATION PROCEDURE
IMPORTANT: Install the auxiliary negative battery cable terminal behind the engine wiring harness
ground terminal.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9238
1. If equipped with a 8.1L engine, install the auxiliary negative battery cable.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the engine wiring harness/auxiliary negative battery cable bolt.
Tighten Tighten the engine wiring harness/auxiliary negative battery cable bolt to 16 N.m (12 lb ft).
IMPORTANT: Install the engine winng harness grounci terminal on top of and inboard of the
auxiliary negative battery cable ground crimp.
3. If equipped with a 4.8L, 5.3L, or 6.OL engine, install the auxiliary negative battery cable. 4. Install
the engine wiring harness/auxiliary negative battery cable bolt.
Tighten Tighten the engine wiring harness/auxiliary negative battery cable bolt to 16 N.m (12 lb ft).
5. Install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Negative, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Negative) > Page 9239
6. Install the auxiliary battery cable clips to the studs at the front of dash. 7. Connect the auxiliary
negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service Precautions
Positive: Service Precautions
BATTERY DISCONNECT CAUTION
CAUTION: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK
position, and all electrical loads must be OFF before servicing any electrical component.
Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment
come in contact with an exposed electrical terminal. Failure to follow these precautions may result
in personal injury and/or damage to the vehicle or its components.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive)
Positive: Service and Repair Battery Cable Replacement (Positive)
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable.
2. Unsnap the positive battery cable cap. 3. Disconnect the positive battery cable.
IMPORTANT: The bolt is integral to the battery cable and is not removable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9245
4. Loosen the positive cable bolt at the underhood bussed electrical center (UBEC).
5. If necessary, remove the engine sight shield. 6. Unsnap the junction block cover. 7. Remove the
positive battery cable (1) from the junction block.
8. If equipped with a 4.8 L, 5.3 L, or 6.0 L engine, remove the negative cable clip from the positive
cable clip. 9. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9246
10. If equipped with a 8.1 L engine, remove the negative cable clip from the positive cable clip. 11.
Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle.
12. Remove the positive battery cable channel bolt. 13. Slide the channel pin out of the oil pan tab.
14. Remove the positive battery cable from the channel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9247
15. If equipped with a 4.8 L, 5.3 L, or 6.0 L engine, remove the battery cable bracket bolt and
bracket from the power steering pump.
16. If equipped with a 4.8 L, 5.3 L, or 6.0 L engine, remove the starter lead nut. 17. Remove the
positive cable from the starter. 18. Remove the positive cable clip from the clip on the oil pan. 19.
Remove the positive cable from the clip on the oil pan. 20. Remove the positive battery cable.
21. If equipped with a 8.1 L engine, remove the starter lead nut. 22. Remove the positive cable
from the starter. 23. Remove the positive cable clip nut. 24. Remove the positive cable from the
engine harness clip. 25. Remove the positive battery cable.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9248
1. If equipped with a 8.1 L engine, install the positive battery cable. 2. Install the positive cable to
the engine harness clip.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the positive cable clip nut.
Tighten Tighten the positive cable clip nut to 8 N.m (71 lb in).
4. Install the positive cable to the starter. 5. Install the starter lead nut.
Tighten Tighten the starter lead nut to 9 N.m (80 lb in).
6. If equipped with a 4.8 L, 5.3 L, or 6.0 L engine, Install the positive battery cable. 7. Install the
positive cable to the clip on the oil pan. 8. Install the positive cable clip to the clip on the oil pan. 9.
Install the positive cable to the starter.
10. Install the starter lead nut.
Tighten Tighten the starter lead nut to 9 N.m (80 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9249
11. IF equipped with a 4.8 L, 5.3 L, or 6.0 L engine, install the battery cable bracket and bolt.
Tighten Tighten the battery cable bracket bolt to 25 N.m (18 lb ft).
12. Install the positive battery cable to the channel. 13. Slide the channel pin into the oil pan tab.
14. Install the positive battery cable channel bolt.
Tighten Tighten the battery cable channel bolt to 12 N.m (106 lb in).
15. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9250
16. If equipped with a 8.1 L engine, install the negative cable clip to the positive cable clip.
17. If equipped with a 4.8 L, 5.3 L, or 6.0 L engine, install the negative cable clip to the positive
cable clip.
18. Install the positive cable (1) into the junction block. 19. Snap the junction block cover closed.
20. If necessary, install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9251
21. Tighten the positive cable bolt at the UBEC.
Tighten Tighten the positive cable bolt at the UBEC to 9 N.m (80 lb in).
22. Connect the positive battery cable.
Tighten Tighten the positive battery cable bolt to 17 N.m (13 lb ft).
23. Snap the positive battery cable cap closed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9252
24. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9253
Positive: Service and Repair Battery Positive Cable Replacement - Auxiliary1
Auxiliary Battery to Battery Relay
REMOVAL PROCEDURE
1. Remove the auxiliary battery. 2. Reposition the boot to expose the stud. 3. Remove the auxiliary
positive cable to relay nut. 4. Unclip the mega fuse from the auxiliary battery tray. 5. Remove the
auxiliary battery positive cable.
INSTALLATION PROCEDURE
1. Install the auxiliary battery positive cable. 2. Clip the mega fuse to the auxiliary battery tray.
NOTE: Refer to Fastener Notice in Service Precautions.
3. Install the auxiliary positive cable nut.
Tighten Tighten the auxiliary positive cable to relay nut to 9 N.m (80 lb in).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9254
4. Position the boot to cover the stud. 5. Install the auxiliary battery.
Battery Relay to Starter
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the auxiliary negative battery cable.
2. Reposition the boot to expose the stud. 3. Remove the auxiliary battery positive cable nut. 5.
Remove the auxiliary battery positive cable to the auxiliary battery relay. 5. Remove the auxiliary
battery positive cable clip from the auxiliary battery tray. 6. Raise and suitably support the vehicle.
refer to Lifting and Jackmg the Vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9255
7. Remove the auxiliary battery positive cable clip bolt from the frame.
8. Remove the positive cable nut. 9. Remove the positive cable from the starter. 10. Remove the
auxiliary positive battery cable from the starter. 11. Remove the auxiliary positive battery cable.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9256
1. Install the auxiliary positive battery cable. 2. Install the auxiliary positive battery cable to the
starter. 3. Install the positive cable to the starter.
NOTE: Refer to Fastener Notice in Service Precautions.
4. Install the positive cable nut.
Tighten Tighten the nut to 9 N.m (80 lb in).
5. Install the auxiliary battery cable clip bolt to the frame.
Tighten Tighten the bolt to 10 N.m (89 lb in).
6. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Battery > Battery Cable > Positive, Battery Cable > System
Information > Service and Repair > Battery Cable Replacement (Positive) > Page 9257
7. Install the auxiliary positive battery cable clip to the auxiliary battery tray.
8. Install the auxiliary battery positive cable to the auxiliary battery relay.
9. Install the auxiliary battery positive cable nut.
Tighten Tighten the auxiliary battery positive cable nut to 8 N.m (71 lb in).
10. Position the boot to cover the stud.
11. Connect the auxiliary negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Specifications > Amperage
Alternator: Specifications Amperage
Application ...........................................................................................................................................
........................................................... Specification
Base
Generator Model ..................................................................................................................................
........................................................... Delphi AD230 Rated Output ....................................................
............................................................................................................................................................
102 A Load Test Output ......................................................................................................................
...................................................................................... 71 A Optional (Dual) Generator Model .........
..............................................................................................................................................................
...................... Delphi AD244 Rated Output .........................................................................................
....................................................................................................................... 130 A Load Test
Output ..................................................................................................................................................
.......................................................... 91 A Bosch® Generator Generator Model ...............................
.......................................................................................................................................................
Bosch® 15755900 Rated Output ........................................................................................................
........................................................................................................ 130 A Load Test Output .............
..............................................................................................................................................................
................................. 91 A
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Specifications > Amperage > Page 9263
Alternator: Specifications Voltage
Voltage
Charging Voltage 13-16 Volts
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Specifications > Page 9264
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions
Alternator: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9267
Electrical Symbols Part 1
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Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9268
Electrical Symbols Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9269
Electrical Symbols Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9270
Electrical Symbols Part 4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9271
Alternator: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9272
J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9273
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information >
Diagrams > Diagram Information and Instructions > Page 9274
With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
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1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
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- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
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7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
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Various symbols are used in order to describe different service operations.
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Diagrams > Diagram Information and Instructions > Page 9296
Conversion - English/Metric
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Diagrams > Diagram Information and Instructions > Page 9297
Generator
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Generator Usage
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Alternator: Description and Operation
GENERATOR
The AD-230 and AD-244 generators are non-repairable. They are electrically similar to earlier
models. The generators feature the following major components:
- The delta stator
- The rectifier bridge
- The rotor with slip rings and brushes
- A conventional pulley
- Dual internal fans
- A voltage regulator
The pulley and the fan cool the slip ring and the frame.
The AD stands for Air-cooled Dual internal fan; the 2 is an electrical design designator; the 30/44
denotes the outside diameter of the stator laminations in millimeters, over 100 millimeters. The
generators is rated at 102 and 130 amperes respectively.
The generator features permanently lubricated bearings. Service should only include the tightening
of mounting components. Otherwise, the generator is replaced as a complete unit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Charging System > Alternator > Component Information > Service
and Repair > Generator Bracket Replacement
Alternator: Service and Repair Generator Bracket Replacement
REMOVAL PROCEDURE
1. Remove the battery cable junction block bracket bolts.
2. Remove the generator. 3. Remove the power steering pump. 4. Remove the generator bracket
bolts. 5. Remove the generator bracket.
INSTALLATION PROCEDURE
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1. Install the generator bracket.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the generator bracket bolts.
Tighten Tighten the generator bracket bolts to 50 N.m (37 lb ft).
3. Install the power steering pump. 4. Install the generator.
5. Install the battery cable junction block bracket bolts.
Tighten Tighten the battery cable junction block bracket bolts to 9 N.m (80 lb in).
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Alternator: Service and Repair Generator Cable Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions
1. Disconnect the negative battery cable. 2. If necessary, remove the engine sight shield.
3. Remove the generator cable from the generator, perform the following:
3.1. Reposition the boot to expose the stud. 3.2. Remove the generator cable nut. 3.3. Remove the
generator cable from the stud.
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4. Open the positive cable junction block. 5. Remove the generator cable nut. 6. Remove the
generator cable (2) from the junction block.
INSTALLATION PROCEDURE
NOTE: Refer to Fastener Notice in Service Precautions.
1. Install the generator cable (2) to the junction block. 2. Install the generator cable nut.
Tighten Tighten the generator cable nut to 9 N.m (80 lb in).
3. Close the positive cable junction block.
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4. Install the generator cable to the generator, perform the following:
4.1. Install the generator cable to the stud. 4.2. Install the generator cable nut.
Tighten Tighten the generator cable nut to 9 N.m (80 lb in).
4.3. Position the boot to cover the stud.
5. If necessary, install the engine sight shield.
6. Connect the negative battery cable.
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Alternator: Service and Repair Generator Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Remove the accessory drive belt. 3. If necessary,
remove the engine sight shield.
4. Disconnect the generator electrical connector (3).
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5. Remove the generator cable from the generator, perform the following:
5.1. Slide the boot down revealing the terminal stud. 5.2. Remove the generator cable nut from the
terminal stud. 5.3. Remove the generator cable.
6. Remove the generator bolts. 7. Remove the generator.
INSTALLATION PROCEDURE
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1. Install the generator.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the generator bolts.
Tighten Tighten the generator bolts to 50 N.m (37 lb ft).
3. Install the generator cable to the generator, perform the following:
3.1. Install the generator cable. 3.2. Install the generator cable nut to the terminal stud.
Tighten Tighten the generator cable nut to 9 N.m (80 lb in).
3.3. Slide the boot over the terminal stud.
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4. Connect the generator electrical connector (3). 5. If necessary, install the engine sight shield. 6.
Install the accessory drive belt.
7. Connect the negative battery cable.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Ignition Lock > Component Information >
Locations
Ignition Lock: Locations
For additional steering column components locations,
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Ignition Switch > Ignition Switch Lock Cylinder >
Component Information > Technical Service Bulletins > Ignition Lock Cylinder - Revised Replacement Procedure
Ignition Switch Lock Cylinder: Technical Service Bulletins Ignition Lock Cylinder - Revised
Replacement Procedure
File In Section: 02 - Steering
Bulletin No.: 02-02-35-001
Date: January, 2002
SERVICE MANUAL UPDATE
Subject: Revised Ignition Lock Cylinder Replacement
Models: 1998-2002 Chevrolet and GMC C/K, S/T, M/L and G Model Vehicles 1999-2000 Cadillac
Escalade 2002 Cadillac Escalade 1998-2002 Oldsmobile Bravada
This bulletin is being issued to revise the Ignition Lock Cylinder Replacement procedure in the
Steering Wheel and Column - Standard or Steering Wheel and Column - Tilt sub-sections of the
Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI2000. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The above mentioned Service Manuals omitted information regarding performing the Passlock
Relearn or Autolearn procedure after an ignition lock cylinder has been replaced. If you have
replaced the ignition lock cylinder, refer to the following procedures:
For 1998-2000 model year vehicles, refer to Passlock Reprogramming in the Theft Deterrent
subsection.
For 2001-2002 model year vehicles, refer to Programming Theft Deterrent System Components in
the Theft Deterrent subsection.
DISCLAIMER
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Key > Component Information > Technical
Service Bulletins > Locks - Key Code Security Rules and Information
Key: Technical Service Bulletins Locks - Key Code Security Rules and Information
INFORMATION
Bulletin No.: 10-00-89-010
Date: May 27, 2010
Subject: Key Code Security Rules and Information on GM KeyCode Look-Up Application (Canada
Only)
Models:
2011 and Prior GM Passenger Cars and Trucks 2010 and Prior HUMMER H2, H3 2009 and Prior
Saturn and Saab 2002 and Prior Isuzu
Attention:
This bulletin has been created to address potential issues and questions regarding KeyCode
security. This bulletin should be read by all parties involved in KeyCode activity, including dealer
operator, partner security coordinator, sales, service and parts departments. A copy of this bulletin
should be printed and maintained in the parts department for use as a reference.
Important U.S. dealers should refer to Corporate Bulletin Number 10-00-89-009.
Where Are Key Codes Located?
General Motors provides access to KeyCodes through three sources when a vehicle is delivered to
a dealer. Vehicle KeyCodes are located on the original vehicle invoice to the dealership. There is a
small white bar coded tag sent with most new vehicles that also has the key code printed on it.
Dealerships should make a practice of comparing the tag's keycode numbers to the keycode listed
on the invoice. Any discrepancy should be reported immediately to the GM of Canada Key Code
Inquiry Desk. Remember to remove the key tag prior to showing vehicles to potential customers.
The third source for Key codes is through the GM KeyCode Look-Up feature within the
OEConnection D2DLink application. KeyCode Look-Up currently goes back 17 previous model
years from the current model year.
When a vehicle is received by the dealership, care should be taken to safeguard the original
vehicle invoice and KeyCode tag provided with the vehicle. Potential customers should not have
access to the invoice or this KeyCode tag prior to the sale being completed. After a sale has been
completed, the KeyCode information belongs to the customer and General Motors.
Tip
Only the original invoice contains key code information, a re-printed invoice does not.
GM KeyCode Look-Up Application for GM of Canada Dealers
All dealers should review the General Motors of Canada KeyCode Look-Up Policies and
Procedures (Service Policy & Procedures Manual Section 3.1.6 "Replacement of VIN plates &
keys").
Please note that the KeyCode Access site is restricted. Only authorized users should be using this
application. Please see your Parts Manager for site authorized users. KeyCode Look-Up currently
goes back 17 years from current model year.
Important notes about security:
- Users may not access the system from multiple computers simultaneously.
- Users may only request one KeyCode at a time.
- KeyCode information will only be available on the screen for 2 minutes.
- Each user is personally responsible for maintaining and protecting their password.
- Never share your password with others.
- User Id's are suspended after 6 consecutive failed attempts.
- User Id's are disabled if not used for 90 days.
- Processes must be in place for regular dealership reviews.
- The Parts Manager (or assigned management) must have processes in place for employee
termination or life change events. Upon termination individuals access must be turned off
immediately and access should be re-evaluated upon any position changes within the dealership.
- If you think your password or ID security has been breached, contact Dealer Systems Support at
1-800-265-0573.
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Each user will be required to accept the following agreement each time the KeyCode application is
used.
Key Code User Agreement
- Key codes are proprietary information belonging to General Motors Corporation and to the vehicle
owner.
- Unauthorized access to, or use of, key code information is unlawful and may subject the user to
criminal and civil penalties.
- This information should be treated as strictly confidential and should not be disclosed to anyone
unless authorized.
I will ensure that the following information is obtained prior to releasing any Key Code information:
1. Government issued picture ID (Drivers License) 2. Registration or other proof of ownership.
Registration should have normal markings from the Province that issued the registration and
possibly the
receipt for payment recorded as well.
Important
- GM takes this agreement seriously. Each user must be certain of vehicle ownership before giving
out key codes.
- When the ownership of the vehicle is in doubt, dealership personnel should not provide the
information.
Key code requests should never be received via a fax or the internet and key codes should never
be provided to anyone in this manner. A face to face contact with the owner of the vehicle is the
expected manner that dealers will use to release a key code or as otherwise stipulated in this
bulletin or other materials.
- Key codes should NEVER be sent via a fax or the internet.
- Each Dealership should create a permanent file to document all KeyCode Look Up transactions.
Requests should be filed by VIN and in each folder retain copies of the following:
- Government issued picture ID (Drivers License)
- Registration or other proof of ownership.
- Copy of the paid customer receipt which has the name of the employee who cut and sold the key
to the customer.
- Do not put yourself or your Dealership in the position of needing to "explain" a KeyCode Look Up
to either GM or law enforcement officials.
- Dealership Management has the ability to review all KeyCode Look-Up transactions.
- Dealership KeyCode documentation must be retained for two years.
Frequently Asked Questions (FAQs) for GM of Canada Dealers
How do I request a KeyCode for customer owned vehicle that is not registered?
Scrapped, salvaged or stored vehicles that do not have a current registration should still have the
ownership verified by requesting the vehicle title, current insurance policy and / or current lien
holder information from the customers financing source. If you cannot determine if the customer is
the owner of the vehicle, do not provide the key code information. In these cases, a short
description of the vehicle (scrapped, salvaged, etc.) and the dealership location should be kept on
file. Any clarifying explanation should be entered into the comments field.
How do I document a KeyCode request for a vehicle that is being repossessed?
The repossessor must document ownership of the vehicle by providing a court ordered
repossession order and lien-holder documents prior to providing key code information. Copies of
the repossessors Drivers License and a business card should be retained by the dealership for
documentation.
What do I do if the registration information is locked in the vehicle?
Every effort should be made to obtain complete information for each request. Each Dealership will
have to decide on a case by case basis if enough information is available to verify the customer's
ownership of the vehicle. Other forms of documentation include vehicle title, insurance policy, and
or current lien information from the customers financing source. Dealership Management must be
involved in any request without complete information. If you cannot determine if the customer is the
owner of the vehicle, do not provide the key code information.
Can I get a print out of the information on the screen?
It is important to note that the Key Code Look Up Search Results contain sensitive and/or
proprietary information. For this reason GM recommends against printing it. If the Search Results
must be printed, store and/or dispose of the printed copy properly to minimize the risk of improper
or illegal use.
Who in the dealership has access to the KeyCode application?
Dealership Parts Manager (or assigned management) will determine, and control, who is
authorized to access the KeyCode Look Up application. However, we anticipate that dealership
parts and service management will be the primary users of the application. The KeyCode Look Up
application automatically tracks each user activity session. Information tracked by the system
includes: User name, User ID, all other entered data and the date/time of access.
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What if I input the VIN incorrectly?
If an incorrect VIN is entered into the system (meaning that the system does not recognize the VIN
or that the VIN has been entered incorrectly) the system will return an error message.
If I am an authorized user for the KeyCode application, can I access the application from home?
Yes.
What if I suspect key code misuse?
Your dealership should communicate the proper procedures for requesting key codes. Any
suspicious activity either within the dealership or externally should be reported to Dealer Systems
Support at 1-800-265-0573 or GM of Canada Key Code Inquiry Desk at 1-905-644-4892.
Whose key codes can I access through the system?
At this time the following Canadian vehicle codes are available through the system: Chevrolet,
Cadillac, Buick, Pontiac, GMC, HUMMER (H2 and H3 only), Oldsmobile, Saturn, Saab and Isuzu
(up to 2002 model year) for a maximum of 17 model years.
What should I do if I enter a valid VIN and the system does not produce any key code information?
Occasionally, the KeyCode Look Up application may not produce a key code for a valid VIN. This
may be the result of new vehicle information not yet available. In addition, older vehicle information
may have been sent to an archive status. If you do not receive a key code returned for valid VIN,
you should contact GM of Canada Key Code Inquiry Desk at 1-905-644-4892.
How do I access KeyCodes if the KeyCode Look-up system is down?
If the KeyCode Look-up system is temporarily unavailable, you can contact the original selling
dealer who may have it on file or contact GM of Canada Key Code Inquiry Desk at
1-905-644-4892. If the customer is dealing with an emergency lock-out situation, you need to have
the customer contact Roadside assistance, OnStar if subscribed, or 911.
What should I do if the KeyCode from the look-up system does not work on the vehicle?
On occasion a dealer may encounter a KeyCode that will not work on the vehicle in question. In
cases where the KeyCode won't work you will need to verify with the manufacturer of the cutting
equipment that the key has been cut correctly. If the key has been cut correctly you may be able to
verify the proper KeyCode was given through the original selling dealer. When unable to verify the
KeyCode through the original selling dealer contact GM of Canada Key Code Inquiry Desk at
1-905-644-4892. If the key has been cut correctly and the code given does not work, the lock
cylinder may have been changed. In these situations following the proper SI document for recoding
a key or replacing the lock cylinder may be necessary.
How long do I have to keep KeyCode Records?
Dealership KeyCode documentation must be retained for two years.
Can I get a KeyCode changed in the Look-Up system?
Yes, KeyCodes can be changed in the Look-Up system if a lock cylinder has been changed.
Contact GM of Canada Key Code Inquiry Desk at 1-905-644-4892.
What information do I need before I can provide a driver of a company fleet vehicle Keys or
KeyCode information?
The dealership should have a copy of the individual's driver's license, proof of employment and
registration. If there is any question as to the customer's employment by the fleet company, the
dealer should attempt to contact the fleet company for verification. If there is not enough
information to determine ownership and employment, this information should not be provided.
How do I document a request from an Independent Repair facility for a KeyCode or Key?
The independent must provide a copy of their driver's license, proof of employment and signed
copy of the repair order for that repair facility. The repair order must include customer's name,
address, VIN, city, province and license plate number. Copies of this information must be included
in your dealer KeyCode file.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Key > Component Information > Technical
Service Bulletins > Locks - Key Code Security Rules and Information > Page 9325
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Motor > Starter Heat Shield >
Component Information > Service and Repair
Starter Heat Shield: Service and Repair
STARTER SHIELD REPLACEMENT
REMOVAL PROCEDURE
1. Remove the starter motor. 2. If equipped with a 4.8L, 5.3L, or 6.0L engine, remove the starter
heat shield.
3. If equipped with a 8.1L engine, remove the starter heat shield bolts, and nut. 4. Remove the
starter heat shield.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Motor > Starter Heat Shield >
Component Information > Service and Repair > Page 9330
1. If equipped with a 8.1L engine, install the starter heat shield.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the starter heat shield bolts, and nut.
Tighten Tighten the starter heat shield bolts to 3 N.m (35 lb in).
- Tighten the starter heat shield nut to 5 N.m (44 lb in).
3. If equipped with a 4.8L, 5.3L, or 6.0L engine, install the starter heat shield. 4. Install the starter
motor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Relay > Component Information >
Locations
Starter Relay: Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Relay > Component Information >
Locations > Page 9334
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Relay > Component Information >
Locations > Page 9335
Starter Relay: Service and Repair
REMOVAL PROCEDURE
1. Remove the underhood bussed electrical center (UBEC) cover. 2. Remove the starter motor
relay.
INSTALLATION PROCEDURE
1. Install the starter motor relay. 2. Install the underhood bussed electrical center (UBEC) cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Starting System > Starter Solenoid > Component Information >
Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Auxiliary Power Outlet >
Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Auxiliary Power Outlet >
Component Information > Locations > Page 9343
Auxiliary Power Outlet: Diagrams
Auxiliary Power Outlet
Auxiliary Power Outlet - Rear
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Auxiliary Power Outlet >
Component Information > Locations > Page 9344
Auxiliary Power Outlet - Console
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Technical Service Bulletins > Electrical - Aftermarket Fuse Warning
Fuse: Technical Service Bulletins Electrical - Aftermarket Fuse Warning
Bulletin No.: 07-08-45-002
Date: September 05, 2007
ADVANCED SERVICE INFORMATION
Subject: Service Alert: Concerns With Aftermarket Fuses in GM Vehicles
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn) 2008 and
Prior HUMMER H2, H3 2008 and Prior Saab 9-7X
Concerns with Harbor Freight Tools "Storehouse" Branded Blade Type Fuses
General Motors has become aware of a fuse recall by Harbor Freight Tools/Storehouse for a
variety of aftermarket fuses. In two cases, these fuses have not provided protection for the wiring
system of the vehicles they were customer installed in.
Upon testing the 15 amp version, it was found that the fuse still would not "open" when shorted
directly across the battery terminals.
How to Identify These Fuses
Packed in a 120 piece set, the fuse has a translucent, hard plastic, blue body with the amperage
stamped into the top. There are no white painted numbers on the fuse to indicate amperage. There
are no identifying marks on the fuse to tell who is making it. The fuses are known to be distributed
by Harbor Freight Tools but there may be other marketers, and packaging of this style of fuse. It
would be prudent to replace these fuses if found in a customers vehicle. Likewise, if wiring
overheating is found you should check the fuse panel for the presence of this style of fuse.
All GM dealers should use genuine GM fuses on the vehicles they service. You should also
encourage the use of GM fuses to your customers to assure they are getting the required electrical
system protection. GM has no knowledge of any concerns with other aftermarket fuses. If
additional information becomes available, this bulletin will be updated.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View
Fuse: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9351
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9352
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9353
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9354
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9355
Fuse: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9356
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Locations > Fuse Block - Underhood Connector View > Page 9357
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood
Fuse: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood > Page 9360
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood > Page 9361
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood > Page 9362
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood > Page 9363
Fuse: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse > Component Information >
Application and ID > Fuse Block - Underhood > Page 9364
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9369
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9370
Fuse Block: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9371
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9372
Fuse Block: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9373
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9374
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Locations > Fuse Block - Location > Page 9375
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P
Fuse Block: Diagrams Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9378
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9379
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9380
Fuse Block: Diagrams Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9381
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9382
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9383
Fuse Block: Diagrams Left I/P
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9384
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9385
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9386
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9387
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9388
Fuse Block: Diagrams
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9389
Fuse Block Fuse Applications Part 2
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9390
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9391
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9392
Fuse Application Part 2
Left I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9393
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9394
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9395
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9396
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9397
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Relay Block
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9398
Relay Block - Body - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9399
Relay Block - Body - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9400
Relay Block - Body - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9401
Relay Block - Body - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9402
Relay Block - Body - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9403
Relay Block - Body - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9404
Relay Block - Body - C4
Relay Block - Body - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9405
Relay Block - Body - C6 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9406
Relay Block - Body - C6 Part 2
Relay Block - Body - C8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9407
Relay Block - Body - C9
Relay Block - Body - C10 Part 1
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9408
Relay Block - Body
Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9409
Fuse Block - Right I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9410
Fuse Block - Right I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9411
Fuse Block - Right I/P - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9412
Fuse Block - Right I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9413
Fuse Block - Right I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9414
Fuse Block - Right I/P - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9415
Fuse Block - Right I/P - C6
Fuse Block - Right I/P - C7 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9416
Fuse Block - Right I/P - C7 Part 2
Fuse Block - Right I/P - C8
Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9417
Relay Block - Underhood - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9418
Relay Block - Underhood - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9419
Relay Block - Underhood - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9420
Relay Block - Underhood - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9421
Relay Block - Underhood - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9422
Relay Block - Underhood - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9423
Relay Block - Underhood - C2 Part 4
Relay Block - Underhood - C3 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9424
Relay Block - Underhood - C3 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9425
Relay Block - Underhood - C4 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9426
Relay Block - Underhood - C4 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9427
Relay Block - Underhood - C4 Part 3
Relay Block - Underhood - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9428
Relay Block - Underhood - C6
Relay Block - Underhood - C7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Diagrams > Fuse Block - Left I/P > Page 9429
Relay Block - Underhood - C8
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P
Fuse Block: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P > Page 9432
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P > Page 9433
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P > Page 9434
Fuse Block: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P > Page 9435
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Application and ID > Fuse Block - Left I/P > Page 9436
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement
Fuse Block: Service and Repair Underhood Electrical Center or Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Remove the left fender upper brace.
3. Remove the electrical center brace cover assemble by lifting the cover (3) outwards to clear the
tabs. 4. Remove all fuses and relays.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9439
5. Push on the tab (3) so that the electrical center can be rotated on the studs located at (2). 6.
Remove all connectors by removing the bolt (1) for each connector. 7. Disconnect all connectors
from the electrical center block.
8. Push on the tabs (2) in order to lift the electrical center (1) out of the housing.
9. To replace the starting and charging center bracket remove the 4 retaining bolts (1).
10. Remove the starting and charging center bracket assembly from the fender.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9440
INSTALLATION PROCEDURE
1. Install the starting and charging center bracket assembly to the front fender.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the 4 retaining bolts (1).
Tighten Tighten the 4 retaining bolts (1) to 9 N.m (80 lb in).
3. Align the electrical center block (1) stubs in the slots so that the tabs (2) retains it in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9441
4. Connect the wire connectors to the lower portion of the electrical center block. 5. Connect the
wire connectors with the bolts to the electrical center block.
Tighten Tighten all connector bolts (1) to 9 N.m (80 lb in).
6. Ensure all wire connectors are securely connected. 7. Set the electrical center block in its resting
position till the tabs (3) locks in place.
8. Install the lower part of the cover (1). 9. With the cover (2) off, use the fuse location information
to install all fuses and relays.
10. Install the cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9442
11. Install the fender upper brace. 12. Install the 4 fender upper brace bolts.
Tighten Tighten the 4 retaining bolts to 25 N.m (18 lb ft).
13. Connect the negative battery cable. 14. Start vehicle and ensure all components function
properly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9443
Fuse Block: Service and Repair I/P Electrical Center or Junction Block Replacement
Left
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the left side end panel. 3. Press on the
clips on the top and the bottom in order to remove the fuse block from the instrument panel (IP)
assembly. 4. Disconnect all wiring connectors from the fuse block. 5. Remove the fuse block from
the vehicle.
INSTALLATION PROCEDURE
1. Connect all wiring connectors to the fuse block. 2. Position the fuse block onto the IP assembly.
3. Press on the clips on the top and the bottom of the fuse block and push in the clips until seated.
4. Install the left side end panel. 5. Connect the negative battery cable(s).
Right
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9444
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the right side end panel. 3. Unclip the
wiring connector(s) from the front of the Instrument Panel (IP) wiring harness junction block Unclip
the harness from the fastener. 4. Remove the IP wiring harness junction block from the IP by
pressing on both of the clips and pulling rearward. 5. Disconnect the lower IP light bulb by twisting
the bulb counterclockwise and pulling the bulb rearward. 6. Feed the IP wiring harness junction
block through the hole in the IP. 7. Disconnect all remaining wiring connectors from the rear of the
IP wiring harness junction block. 8. Remove the IP wiring harness junction block from the vehicle.
INSTALLATION PROCEDURE
1. Connect the wiring connectors to the rear of the IP wiring harness junction block. 2. Feed the IP
wiring harness junction block through the hole in the IP. 3. Connect the lower IP light bulb by
twisting the bulb socket clockwise while pushing in. 4. Connect the IP wiring harness junction block
to the IP by pressing on both clips and pushing until sealed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9445
5. Connect the wiring connector(s) onto the front of the IP wiring harness junction block and
connect the harness to the fastener. 6. Install the right side end panel. 7. Connect the negative
battery cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9446
Fuse Block: Service and Repair Body Wiring Harness Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the harness from the front of the body
wiring harness junction block. 3. Unsnap the cover from the body wiring harness junction block.
4. Unsnap the top pivots and rotate the body wiring harness junction block (1) down. Unsnap the
lower pivots and remove the body wiring harness
junction block from the bracket (2).
5. Disconnect the two 68-way IP connectors. 6. Disconnect the remaining wiring connectors from
the body wiring harness junction block. 7. Remove the body wiring harness junction block from the
vehicle.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Fuse Block > Component
Information > Service and Repair > Underhood Electrical Center or Junction Block Replacement > Page 9447
1. Connect the two 68-way IP connectors to the body wiring harness junction block. 2. Connect all
remaining wiring connectors. 3. Snap the body wiring harness junction block (1) onto the bracket
(2). 4. Connect the harness to the front of the body wiring harness junction block.
5. Fasten the cover to the body wiring harness junction block. 6. Connect the negative battery
cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > Customer Interest for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine
Controls - MIL ON/Misfire/Misfire DTC's Set
Ground Strap: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > Customer Interest for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine
Controls - MIL ON/Misfire/Misfire DTC's Set > Page 9456
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Ground Strap: > 06-06-04-046 > Sep > 06 >
Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Ground Strap: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Ground Strap: > 06-06-04-046 > Sep > 06 >
Engine Controls - MIL ON/Misfire/Misfire DTC's Set > Page 9462
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > Page 9463
Ground Strap: Service and Repair
GROUND STRAP REPLACEMENT
REMOVAL PROCEDURE
1. If necessary, remove the engine sight shield. 2. Remove the engine wiring harness ground bolt.
3. Reposition the engine wiring harness ground and ground strap.
4. Remove the ground strap nut from the stud at the front of dash. 5. Remove the ground strap
from the stud.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Ground Strap > Component
Information > Technical Service Bulletins > Page 9464
1. Install the ground strap to the stud.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ground strap nut to the stud at the front of dash.
Tighten Tighten the ground strap nut to 9 N.m (80 lb in).
3. Position the ground strap and engine wiring harness ground. 4. Install the engine wiring harness
ground bolt.
Tighten Tighten the engine wiring harness ground bolt to 16 N.m (12 lb ft).
5. If necessary, install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > Customer Interest: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp
ON/DTC's C0265/C0201/U1041 Set
Grounding Point: Customer Interest Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > Customer Interest: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp
ON/DTC's C0265/C0201/U1041 Set > Page 9473
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair
Grounding Point: All Technical Service Bulletins Electrical - Information For Electrical Ground
Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9479
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9480
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9481
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9482
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9483
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9484
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 04-05-25-002E > Mar > 09
> Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
Grounding Point: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Grounding Point: > 04-05-25-002E > Mar > 09
> Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set > Page 9489
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair
Grounding Point: All Technical Service Bulletins Electrical - Information For Electrical Ground
Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9495
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9496
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9497
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9498
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9499
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Grounding Point > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9500
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199
Multiple Junction Connector: Diagrams C100 - C199
C100
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9505
C102
C103 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9506
C103 Part 2
C104 Z75 Only
C104 Z75 Only Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9507
C104 Z75 Only Part 2
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C114 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9508
C114 Part 2
C117
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9509
C118
C125 Snowplow
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9510
C127 Snowplow
C148 Odd Ignition Coils Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9511
C148 Odd Ignition Coils Part 2
C149 Even Ignition Coils
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9512
C150 4WD JMPR
C151
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9513
C152
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9514
C153
C154
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9515
C198 H.D. Trailer Wiring
C199 Camper Wiring
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9516
Multiple Junction Connector: Diagrams C200 - C299
C200
C200 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9517
C200 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9518
C200 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C201 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9519
C201 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9520
C201 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9521
C202
C204
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9522
C204
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C205
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9523
C205
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9524
C206
C207 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9525
C207 Part 2
C208
C208 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9526
C208 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9527
C208 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9528
C209 (806)
C210
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9529
C211
C212
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9530
C212 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9531
C212 Part 2
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9532
C216
C217
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9533
C218
C248 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9534
C248 Part 2
C249
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9535
C251
C252
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9536
C253
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9537
C254
C290 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9538
C290 Part 2
C296 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9539
C296 Part 2
C298
C299 Uplevel
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9540
C299 Uplevel Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9541
C299 Uplevel Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9542
C299 Uplevel Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9543
Multiple Junction Connector: Diagrams C303 - C399
C303 Connection To Seat Harness
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9544
C305 Connection To Seat Harness
C306 Y91/Z75
C306 Y91/Z75 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9545
C306 Y91/Z75 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9546
C306 Y91/Z75 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9547
C307
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9548
C310
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9549
C312
C313 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9550
C313 Part 2
C314 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9551
C314 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9552
C314 Part 3
C315
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9553
C320
C321 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9554
C321 Part 2
C322 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9555
C322 Part 2
C323 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9556
C323 Part 2
C324
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9557
C325
C326
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9558
C327 Seat Harness Connector Luxury
C328
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9559
C330 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9560
C330 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9561
C340 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9562
C340 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9563
C341
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9564
C349
C350 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9565
C350 Part 2
C351
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9566
C353
C387
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9567
C388
C389
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9568
C390
C395
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9569
C396 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9570
C396 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9571
C397
C398 Connection To Seat Harness
C399 Connection To Seat Harness
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9572
Multiple Junction Connector: Diagrams C402 - C499
C402
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9573
C403
C404
C405
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9574
C406 Part 1
C406 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9575
C450 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9576
C450 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9577
C450 Part 3
C495
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9578
C497 - Luxury Utility Part 1
C497 - Luxury Utility Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9579
C499 Part 1
C499 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Multiple Junction Connector >
Component Information > Diagrams > C100 - C199 > Page 9580
Multiple Junction Connector: Diagrams C900 - C901
C900
C901
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Power Interrupt Connector/Switch
> Component Information > Description and Operation
Power Interrupt Connector/Switch: Description and Operation
BATTERY RUNDOWN PROTECTION/INADVERTENT POWER
In the event that any of the interior lamps supplied voltage by the inadvertent power relay and
ground from the courtesy lamp relay were to remain on when the ignition is OFF after a period of
20 minutes, the BCM will deactivate the inadvertent power relay turning OFF all of the lamps on
that circuit to prevent total battery discharge. Only when the ignition switch is cycled back to the
RUN position will the BCM reset the internal timer and reactivate the inadvertent power relay.
When the inadvertent power relay is not energized, the BCM utilizes the inadvertent power
courtesy lamp supply voltage circuit to monitor for a courtesy lamp switch request signal. If a
courtesy lamp switch is activated, the BCM will receive the signal to energize the inadvertent power
relay by grounding the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Locations > Page 9588
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Locations > Page 9589
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Locations > Page 9590
Junction Block - Rear Lamps - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical
Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical
Center) > Page 9593
1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relays and Modules - Power and
Ground Distribution > Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical
Center) > Page 9594
Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Locations > Page 9598
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Locations > Page 9599
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Locations > Page 9600
Junction Block - Rear Lamps - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Service and Repair > Relay Replacement (Within an Electrical Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Service and Repair > Relay Replacement (Within an Electrical Center) > Page 9603
1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Relay Box > Component
Information > Service and Repair > Relay Replacement (Within an Electrical Center) > Page 9604
Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Sensors and Switches - Power
and Ground Distribution > Power Interrupt Connector/Switch > Component Information > Description and Operation
Power Interrupt Connector/Switch: Description and Operation
BATTERY RUNDOWN PROTECTION/INADVERTENT POWER
In the event that any of the interior lamps supplied voltage by the inadvertent power relay and
ground from the courtesy lamp relay were to remain on when the ignition is OFF after a period of
20 minutes, the BCM will deactivate the inadvertent power relay turning OFF all of the lamps on
that circuit to prevent total battery discharge. Only when the ignition switch is cycled back to the
RUN position will the BCM reset the internal timer and reactivate the inadvertent power relay.
When the inadvertent power relay is not energized, the BCM utilizes the inadvertent power
courtesy lamp supply voltage circuit to monitor for a courtesy lamp switch request signal. If a
courtesy lamp switch is activated, the BCM will receive the signal to energize the inadvertent power
relay by grounding the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set
By Various Control Modules
Wiring Harness: Customer Interest Electrical - MIL ON/DTC's Set By Various Control Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set
By Various Control Modules > Page 9617
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set
By Various Control Modules > Page 9618
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set
By Various Control Modules > Page 9619
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10
> Electrical - MIL ON/DTC's Set By Various Control Modules
Wiring Harness: All Technical Service Bulletins Electrical - MIL ON/DTC's Set By Various Control
Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10
> Electrical - MIL ON/DTC's Set By Various Control Modules > Page 9625
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10
> Electrical - MIL ON/DTC's Set By Various Control Modules > Page 9626
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10
> Electrical - MIL ON/DTC's Set By Various Control Modules > Page 9627
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair
Wiring Harness: All Technical Service Bulletins Electrical - Information For Electrical Ground Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9632
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9633
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9634
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9635
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9636
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10
> Electrical - Information For Electrical Ground Repair > Page 9637
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 >
Electrical - Instrument Panel & General Wiring Repair
Wiring Harness: All Technical Service Bulletins Electrical - Instrument Panel & General Wiring
Repair
Bulletin No.: 06-08-45-004
Date: May 02, 2006
INFORMATION
Subject: Instrument Panel (I/P), Body and General Wiring Harness Repair
Models: 2007 and Prior GM Cars and Trucks 2003-2007 HUMMER H2 2006-2007 HUMMER H3
Important:
A part restriction has been implemented on all Body and I/P harnesses and is being administered
by the PQC. If a body or I/P harness replacement is required, it can take 12-28 weeks for a
harness to be built and delivered to a dealer. The dealer technician is expected to repair any
harness damage as the first and best choice before replacing a harness.
In an effort to standardize repair practices, General Motors is requiring that all wiring harnesses be
repaired instead of replaced. If there is a question concerning which connector and/or terminal you
are working on, refer to the information in the appropriate Connector End Views in SI. The
Instruction Manual J 38125-620, which is sent with each new update of the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal remove information.
Important:
There are some parts in the J 38125 Terminal Repair Kit (i.e. SIR connector CPAs and heat shrink
tube (used in high heat area pigtail replacement) and some TPAs that are not available from
GMSPO. It is vitally important that each update to the J 38125 Terminal Repair Kit be done as soon
as it arrives at the dealer.
Utilize the Terminal Repair Kit (J 38125) to achieve an effective wiring repair. The Terminal Repair
Kit has been an essential tool for all GM Dealers since 1987. Replacement terminals and tools for
this kit are available through SPX/Kent Moore. Refer to Corporate Bulletin Number 06-08-45-001
for more information.
The Instruction Manual J 38125-620, which is sent with each new update to the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal removal information.
U.S. Dealers Only - Training courses (including Tech Assists, Emerging Issues, Web, IDL and
Hands-on) are available through the GM Training website. Refer to Resources and then Training
Materials for a complete list of available courses.
Canadian Dealers Only - Refer to the Training section of GM infoNet for a complete list of available
courses and a copy of the J 38125 Terminal Repair Kit Instruction Manual.
Wiring repair information is also available in Service Information (SI). The Wiring Repair section
contains information for the following types of wiring repairs:
- Testing for intermittent conditions and poor conditions
- Flat wire repairs
- GMLAN wiring repairs
- High temperature wiring repairs
- Splicing copper wire using splice clips
- Splicing copper wire using splice sleeves
- Splicing twisted or shielded cable
- Splicing inline harness diodes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 >
Electrical - Instrument Panel & General Wiring Repair > Page 9642
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair
Wiring Harness: All Technical Service Bulletins Electrical - Information For Electrical Ground Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9648
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9649
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9650
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9651
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9652
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 >
Electrical - Information For Electrical Ground Repair > Page 9653
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 >
Electrical - Instrument Panel & General Wiring Repair
Wiring Harness: All Technical Service Bulletins Electrical - Instrument Panel & General Wiring
Repair
Bulletin No.: 06-08-45-004
Date: May 02, 2006
INFORMATION
Subject: Instrument Panel (I/P), Body and General Wiring Harness Repair
Models: 2007 and Prior GM Cars and Trucks 2003-2007 HUMMER H2 2006-2007 HUMMER H3
Important:
A part restriction has been implemented on all Body and I/P harnesses and is being administered
by the PQC. If a body or I/P harness replacement is required, it can take 12-28 weeks for a
harness to be built and delivered to a dealer. The dealer technician is expected to repair any
harness damage as the first and best choice before replacing a harness.
In an effort to standardize repair practices, General Motors is requiring that all wiring harnesses be
repaired instead of replaced. If there is a question concerning which connector and/or terminal you
are working on, refer to the information in the appropriate Connector End Views in SI. The
Instruction Manual J 38125-620, which is sent with each new update of the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal remove information.
Important:
There are some parts in the J 38125 Terminal Repair Kit (i.e. SIR connector CPAs and heat shrink
tube (used in high heat area pigtail replacement) and some TPAs that are not available from
GMSPO. It is vitally important that each update to the J 38125 Terminal Repair Kit be done as soon
as it arrives at the dealer.
Utilize the Terminal Repair Kit (J 38125) to achieve an effective wiring repair. The Terminal Repair
Kit has been an essential tool for all GM Dealers since 1987. Replacement terminals and tools for
this kit are available through SPX/Kent Moore. Refer to Corporate Bulletin Number 06-08-45-001
for more information.
The Instruction Manual J 38125-620, which is sent with each new update to the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal removal information.
U.S. Dealers Only - Training courses (including Tech Assists, Emerging Issues, Web, IDL and
Hands-on) are available through the GM Training website. Refer to Resources and then Training
Materials for a complete list of available courses.
Canadian Dealers Only - Refer to the Training section of GM infoNet for a complete list of available
courses and a copy of the J 38125 Terminal Repair Kit Instruction Manual.
Wiring repair information is also available in Service Information (SI). The Wiring Repair section
contains information for the following types of wiring repairs:
- Testing for intermittent conditions and poor conditions
- Flat wire repairs
- GMLAN wiring repairs
- High temperature wiring repairs
- Splicing copper wire using splice clips
- Splicing copper wire using splice sleeves
- Splicing twisted or shielded cable
- Splicing inline harness diodes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Starting and Charging > Power and Ground Distribution > Wiring Harness > Component
Information > Technical Service Bulletins > All Other Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 >
Electrical - Instrument Panel & General Wiring Repair > Page 9658
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Auxiliary Power Outlet > Component Information >
Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Auxiliary Power Outlet > Component Information >
Locations > Page 9663
Auxiliary Power Outlet: Diagrams
Auxiliary Power Outlet
Auxiliary Power Outlet - Rear
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Auxiliary Power Outlet > Component Information >
Locations > Page 9664
Auxiliary Power Outlet - Console
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Technical Service
Bulletins > Electrical - Aftermarket Fuse Warning
Fuse: Technical Service Bulletins Electrical - Aftermarket Fuse Warning
Bulletin No.: 07-08-45-002
Date: September 05, 2007
ADVANCED SERVICE INFORMATION
Subject: Service Alert: Concerns With Aftermarket Fuses in GM Vehicles
Models: 2008 and Prior GM Passenger Cars and Light Duty Trucks (including Saturn) 2008 and
Prior HUMMER H2, H3 2008 and Prior Saab 9-7X
Concerns with Harbor Freight Tools "Storehouse" Branded Blade Type Fuses
General Motors has become aware of a fuse recall by Harbor Freight Tools/Storehouse for a
variety of aftermarket fuses. In two cases, these fuses have not provided protection for the wiring
system of the vehicles they were customer installed in.
Upon testing the 15 amp version, it was found that the fuse still would not "open" when shorted
directly across the battery terminals.
How to Identify These Fuses
Packed in a 120 piece set, the fuse has a translucent, hard plastic, blue body with the amperage
stamped into the top. There are no white painted numbers on the fuse to indicate amperage. There
are no identifying marks on the fuse to tell who is making it. The fuses are known to be distributed
by Harbor Freight Tools but there may be other marketers, and packaging of this style of fuse. It
would be prudent to replace these fuses if found in a customers vehicle. Likewise, if wiring
overheating is found you should check the fuse panel for the presence of this style of fuse.
All GM dealers should use genuine GM fuses on the vehicles they service. You should also
encourage the use of GM fuses to your customers to assure they are getting the required electrical
system protection. GM has no knowledge of any concerns with other aftermarket fuses. If
additional information becomes available, this bulletin will be updated.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View
Fuse: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9671
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9672
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9673
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9674
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9675
Fuse: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9676
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Locations > Fuse Block
- Underhood Connector View > Page 9677
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood
Fuse: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood > Page 9680
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood > Page 9681
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood > Page 9682
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood > Page 9683
Fuse: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse > Component Information > Application and ID >
Fuse Block - Underhood > Page 9684
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9689
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9690
Fuse Block: Locations Fuse Block - Underhood
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9691
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9692
Fuse Block: Locations Fuse Block - Underhood Connector View
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9693
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9694
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Locations > Fuse
Block - Location > Page 9695
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P
Fuse Block: Diagrams Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9698
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9699
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9700
Fuse Block: Diagrams Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9701
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9702
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9703
Fuse Block: Diagrams Left I/P
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9704
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9705
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9706
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9707
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9708
Fuse Block: Diagrams
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9709
Fuse Block Fuse Applications Part 2
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9710
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9711
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9712
Fuse Application Part 2
Left I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9713
Fuse Block - Left I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9714
Fuse Block - Left I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9715
Fuse Block - Left I/P - C1 Part 3
Fuse Block - Left I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9716
Fuse Block - Left I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9717
Fuse Block - Left I/P - C6
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Relay Block
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9718
Relay Block - Body - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9719
Relay Block - Body - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9720
Relay Block - Body - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9721
Relay Block - Body - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9722
Relay Block - Body - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9723
Relay Block - Body - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9724
Relay Block - Body - C4
Relay Block - Body - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9725
Relay Block - Body - C6 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9726
Relay Block - Body - C6 Part 2
Relay Block - Body - C8
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9727
Relay Block - Body - C9
Relay Block - Body - C10 Part 1
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9728
Relay Block - Body
Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9729
Fuse Block - Right I/P - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9730
Fuse Block - Right I/P - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9731
Fuse Block - Right I/P - C2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9732
Fuse Block - Right I/P - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9733
Fuse Block - Right I/P - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9734
Fuse Block - Right I/P - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9735
Fuse Block - Right I/P - C6
Fuse Block - Right I/P - C7 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9736
Fuse Block - Right I/P - C7 Part 2
Fuse Block - Right I/P - C8
Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9737
Relay Block - Underhood - C1 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9738
Relay Block - Underhood - C1 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9739
Relay Block - Underhood - C1 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9740
Relay Block - Underhood - C2 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9741
Relay Block - Underhood - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9742
Relay Block - Underhood - C2 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9743
Relay Block - Underhood - C2 Part 4
Relay Block - Underhood - C3 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9744
Relay Block - Underhood - C3 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9745
Relay Block - Underhood - C4 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9746
Relay Block - Underhood - C4 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9747
Relay Block - Underhood - C4 Part 3
Relay Block - Underhood - C5
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9748
Relay Block - Underhood - C6
Relay Block - Underhood - C7
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Diagrams > Fuse
Block - Left I/P > Page 9749
Relay Block - Underhood - C8
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P
Fuse Block: Application and ID Fuse Block - Left I/P
Fuse Block - Left I/P
Fuse Block Fuse Applications Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P > Page 9752
Fuse Block Fuse Applications Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P > Page 9753
Fuse Block - Right I/P
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P > Page 9754
Fuse Block: Application and ID Fuse Block - Underhood
Fuse Block - Underhood
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P > Page 9755
Fuse Application Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Application and ID
> Fuse Block - Left I/P > Page 9756
Fuse Application Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement
Fuse Block: Service and Repair Underhood Electrical Center or Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable. 2. Remove the left fender upper brace.
3. Remove the electrical center brace cover assemble by lifting the cover (3) outwards to clear the
tabs. 4. Remove all fuses and relays.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9759
5. Push on the tab (3) so that the electrical center can be rotated on the studs located at (2). 6.
Remove all connectors by removing the bolt (1) for each connector. 7. Disconnect all connectors
from the electrical center block.
8. Push on the tabs (2) in order to lift the electrical center (1) out of the housing.
9. To replace the starting and charging center bracket remove the 4 retaining bolts (1).
10. Remove the starting and charging center bracket assembly from the fender.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9760
INSTALLATION PROCEDURE
1. Install the starting and charging center bracket assembly to the front fender.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the 4 retaining bolts (1).
Tighten Tighten the 4 retaining bolts (1) to 9 N.m (80 lb in).
3. Align the electrical center block (1) stubs in the slots so that the tabs (2) retains it in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9761
4. Connect the wire connectors to the lower portion of the electrical center block. 5. Connect the
wire connectors with the bolts to the electrical center block.
Tighten Tighten all connector bolts (1) to 9 N.m (80 lb in).
6. Ensure all wire connectors are securely connected. 7. Set the electrical center block in its resting
position till the tabs (3) locks in place.
8. Install the lower part of the cover (1). 9. With the cover (2) off, use the fuse location information
to install all fuses and relays.
10. Install the cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9762
11. Install the fender upper brace. 12. Install the 4 fender upper brace bolts.
Tighten Tighten the 4 retaining bolts to 25 N.m (18 lb ft).
13. Connect the negative battery cable. 14. Start vehicle and ensure all components function
properly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9763
Fuse Block: Service and Repair I/P Electrical Center or Junction Block Replacement
Left
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the left side end panel. 3. Press on the
clips on the top and the bottom in order to remove the fuse block from the instrument panel (IP)
assembly. 4. Disconnect all wiring connectors from the fuse block. 5. Remove the fuse block from
the vehicle.
INSTALLATION PROCEDURE
1. Connect all wiring connectors to the fuse block. 2. Position the fuse block onto the IP assembly.
3. Press on the clips on the top and the bottom of the fuse block and push in the clips until seated.
4. Install the left side end panel. 5. Connect the negative battery cable(s).
Right
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9764
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the right side end panel. 3. Unclip the
wiring connector(s) from the front of the Instrument Panel (IP) wiring harness junction block Unclip
the harness from the fastener. 4. Remove the IP wiring harness junction block from the IP by
pressing on both of the clips and pulling rearward. 5. Disconnect the lower IP light bulb by twisting
the bulb counterclockwise and pulling the bulb rearward. 6. Feed the IP wiring harness junction
block through the hole in the IP. 7. Disconnect all remaining wiring connectors from the rear of the
IP wiring harness junction block. 8. Remove the IP wiring harness junction block from the vehicle.
INSTALLATION PROCEDURE
1. Connect the wiring connectors to the rear of the IP wiring harness junction block. 2. Feed the IP
wiring harness junction block through the hole in the IP. 3. Connect the lower IP light bulb by
twisting the bulb socket clockwise while pushing in. 4. Connect the IP wiring harness junction block
to the IP by pressing on both clips and pushing until sealed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9765
5. Connect the wiring connector(s) onto the front of the IP wiring harness junction block and
connect the harness to the fastener. 6. Install the right side end panel. 7. Connect the negative
battery cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9766
Fuse Block: Service and Repair Body Wiring Harness Junction Block Replacement
REMOVAL PROCEDURE
CAUTION: Refer to Battery Disconnect Caution in Service Precautions.
1. Disconnect the negative battery cable(s). 2. Remove the harness from the front of the body
wiring harness junction block. 3. Unsnap the cover from the body wiring harness junction block.
4. Unsnap the top pivots and rotate the body wiring harness junction block (1) down. Unsnap the
lower pivots and remove the body wiring harness
junction block from the bracket (2).
5. Disconnect the two 68-way IP connectors. 6. Disconnect the remaining wiring connectors from
the body wiring harness junction block. 7. Remove the body wiring harness junction block from the
vehicle.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Fuse Block > Component Information > Service and
Repair > Underhood Electrical Center or Junction Block Replacement > Page 9767
1. Connect the two 68-way IP connectors to the body wiring harness junction block. 2. Connect all
remaining wiring connectors. 3. Snap the body wiring harness junction block (1) onto the bracket
(2). 4. Connect the harness to the front of the body wiring harness junction block.
5. Fasten the cover to the body wiring harness junction block. 6. Connect the negative battery
cable(s).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > Customer Interest for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set
Ground Strap: Customer Interest Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > Customer Interest for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set > Page 9776
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set
Ground Strap: All Technical Service Bulletins Engine Controls - MIL ON/Misfire/Misfire DTC's Set
Bulletin No.: 06-06-04-046
Date: September 12, 2006
INFORMATION
Subject: Information on Engine Misfire MIL/SES Light Illuminated or Flashing DTC P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0307, P0308, P0420 or P0430
Models: 1999-2007 Cadillac, Chevrolet, GMC Full-Size Pickup and/or Utility Trucks
with 4.8L, 5.3L, 5.7L, 6.0L or 6.2L VORTEC GEN III, GEN IV, V-8 Engine (VINs V, C, T, Z, B, 3, M,
0, J, R, U, N, Y, K, 8 - RPOs LR4, LY2, LM7, L59, L33, LC9, LH6, LMG, LY5, L31, LQ4, LQ9, L76,
LY6, L92)
with Active Fuel Management(TM) and E85 Flex Fuel
If you encounter vehicles that exhibit the above conditions, refer to SI for the appropriate DTC(s)
set. If no trouble is found, the cause may be due to an ECM ground terminal that has corroded with
rust over time. Inspect the main engine wiring harness ground terminal (G103) for this condition.
The wire terminal (G103) attaches either to the front or to the rear of the right side cylinder head,
depending on the model year of the Full Size Pickup and/or Utility Trucks. If the ECM ground
terminal has been found to be corroded, then follow the service procedure outlined in this bulletin to
correct the corrosion issue.
Remove either the nut or bolt securing the main engine wiring harness ground terminal (G103) to
the right cylinder head. Refer to the above illustration to determine where the ground is located on
the vehicle (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Ground Strap: > 06-06-04-046 > Sep > 06 > Engine Controls - MIL
ON/Misfire/Misfire DTC's Set > Page 9782
Remove all rust from the ground terminal, the cylinder head and the retaining nut or bolt.
Position the main engine wiring harness ground terminal and install the nut or bolt.
Tighten:
Tighten the retaining nut or bolt to 16 N.m (12 lb ft).
Apply some type of electrical moisture sealant to protect the harness terminal from further
corrosion.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > Page 9783
Ground Strap: Service and Repair
GROUND STRAP REPLACEMENT
REMOVAL PROCEDURE
1. If necessary, remove the engine sight shield. 2. Remove the engine wiring harness ground bolt.
3. Reposition the engine wiring harness ground and ground strap.
4. Remove the ground strap nut from the stud at the front of dash. 5. Remove the ground strap
from the stud.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Ground Strap > Component Information > Technical
Service Bulletins > Page 9784
1. Install the ground strap to the stud.
NOTE: Refer to Fastener Notice in Service Precautions.
2. Install the ground strap nut to the stud at the front of dash.
Tighten Tighten the ground strap nut to 9 N.m (80 lb in).
3. Position the ground strap and engine wiring harness ground. 4. Install the engine wiring harness
ground bolt.
Tighten Tighten the engine wiring harness ground bolt to 16 N.m (12 lb ft).
5. If necessary, install the engine sight shield.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > Customer Interest: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041
Set
Grounding Point: Customer Interest Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > Customer Interest: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp ON/DTC's C0265/C0201/U1041
Set > Page 9793
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair
Grounding Point: All Technical Service Bulletins Electrical - Information For Electrical Ground
Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9799
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9800
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9801
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9802
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9803
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical Information For Electrical Ground Repair > Page 9804
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp
ON/DTC's C0265/C0201/U1041 Set
Grounding Point: All Technical Service Bulletins Brakes - ABS Lamp ON/DTC's
C0265/C0201/U1041 Set
TECHNICAL
Bulletin No.: 04-05-25-002E
Date: March 11, 2009
Subject: ABS Light On, DTCs C0265, C0201, U1041 Set and/or Loss of Communication with Brake
Module (Reground EBCM Ground)
Models
Supercede:
This bulletin is being revised to add step 2 to the procedure and update the Parts and Warranty
Information. Please discard Corporate Bulletin Number 04-05-25-002D (Section 05 - Brakes).
Condition
Some customers may comment that the ABS light is on. Upon further inspection, DTCs C0265 and
C0201 may be set in the brake module. It is also possible for DTC U1041 to set in other modules.
There may also be a loss of communication with the brake module.
Cause
A poor connection at the EBCM ground is causing unnecessary replacement of brake modules.
Important:
The EBCM ground is different for each application. Refer to the list below for the proper ground
reference:
^ Midsize Utilities = Ground 304
^ SSR = Ground 400
^ Fullsize Trucks and Utilities = Ground 110
Correction
Important:
Do not replace the brake module to correct this condition. Perform the following repair before
further diagnosis of the EBCM.
Perform the following steps to improve the connection of the EBCM Ground:
1. Remove the EBCM Ground. The EBCM Ground is located on the frame beneath the driver's side
door. If multiple grounds are found in this location, the EBCM ground can be identified as the heavy
(12-gauge) wire.
2. If the original fastener has a welded on nut, remove the nut from the frame, and if required,
enlarge the bolt hole to accommodate the new bolt and nut.
3. Clean the area, front and back, using a tool such as a *3M(TM) Scotch-Brite Roloc disc or
equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Grounding Point: > 04-05-25-002E > Mar > 09 > Brakes - ABS Lamp
ON/DTC's C0265/C0201/U1041 Set > Page 9809
4. Install the ground, then the washer and then the bolt to the frame.
Important:
It is important to use the bolts, washers and nuts specified in this bulletin. These parts have been
identified due to their conductive finish.
5. Install a washer and nut to the back side of the frame.
Tighten
Tighten the nut to 9 Nm (79 lb in).
6. Cover the front and back side of the repair area using Rubberized Undercoating.
An additional check can be made to ensure a good connection for the battery cable to frame
ground. It is possible for this ground to cause similar symptoms with the ABS as described above.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Parts Information
Warranty Information
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair
Grounding Point: All Technical Service Bulletins Electrical - Information For Electrical Ground
Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9815
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9816
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9817
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9818
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9819
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Grounding Point > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Grounding Point: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9820
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199
Multiple Junction Connector: Diagrams C100 - C199
C100
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9825
C102
C103 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9826
C103 Part 2
C104 Z75 Only
C104 Z75 Only Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9827
C104 Z75 Only Part 2
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C114 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9828
C114 Part 2
C117
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9829
C118
C125 Snowplow
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9830
C127 Snowplow
C148 Odd Ignition Coils Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9831
C148 Odd Ignition Coils Part 2
C149 Even Ignition Coils
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9832
C150 4WD JMPR
C151
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9833
C152
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9834
C153
C154
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9835
C198 H.D. Trailer Wiring
C199 Camper Wiring
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9836
Multiple Junction Connector: Diagrams C200 - C299
C200
C200 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9837
C200 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9838
C200 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C201 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9839
C201 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9840
C201 Part 3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9841
C202
C204
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9842
C204
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
C205
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9843
C205
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9844
C206
C207 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9845
C207 Part 2
C208
C208 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9846
C208 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9847
C208 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9848
C209 (806)
C210
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9849
C211
C212
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9850
C212 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9851
C212 Part 2
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9852
C216
C217
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9853
C218
C248 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9854
C248 Part 2
C249
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9855
C251
C252
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9856
C253
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9857
C254
C290 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9858
C290 Part 2
C296 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9859
C296 Part 2
C298
C299 Uplevel
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9860
C299 Uplevel Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9861
C299 Uplevel Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9862
C299 Uplevel Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9863
Multiple Junction Connector: Diagrams C303 - C399
C303 Connection To Seat Harness
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9864
C305 Connection To Seat Harness
C306 Y91/Z75
C306 Y91/Z75 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9865
C306 Y91/Z75 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9866
C306 Y91/Z75 Part 3
For a description of the RPO Code(s) shown in this article or any of the images therein, refer to the
RPO Code List found at Vehicle/Application ID". See: Application and ID/RPO Codes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9867
C307
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9868
C310
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9869
C312
C313 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9870
C313 Part 2
C314 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9871
C314 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9872
C314 Part 3
C315
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9873
C320
C321 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9874
C321 Part 2
C322 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9875
C322 Part 2
C323 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9876
C323 Part 2
C324
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9877
C325
C326
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9878
C327 Seat Harness Connector Luxury
C328
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9879
C330 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9880
C330 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9881
C340 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9882
C340 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9883
C341
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9884
C349
C350 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9885
C350 Part 2
C351
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9886
C353
C387
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9887
C388
C389
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9888
C390
C395
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9889
C396 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9890
C396 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9891
C397
C398 Connection To Seat Harness
C399 Connection To Seat Harness
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9892
Multiple Junction Connector: Diagrams C402 - C499
C402
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9893
C403
C404
C405
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9894
C406 Part 1
C406 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9895
C450 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9896
C450 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9897
C450 Part 3
C495
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9898
C497 - Luxury Utility Part 1
C497 - Luxury Utility Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9899
C499 Part 1
C499 Part 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Multiple Junction Connector > Component Information >
Diagrams > C100 - C199 > Page 9900
Multiple Junction Connector: Diagrams C900 - C901
C900
C901
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Power Interrupt Connector/Switch > Component
Information > Description and Operation
Power Interrupt Connector/Switch: Description and Operation
BATTERY RUNDOWN PROTECTION/INADVERTENT POWER
In the event that any of the interior lamps supplied voltage by the inadvertent power relay and
ground from the courtesy lamp relay were to remain on when the ignition is OFF after a period of
20 minutes, the BCM will deactivate the inadvertent power relay turning OFF all of the lamps on
that circuit to prevent total battery discharge. Only when the ignition switch is cycled back to the
RUN position will the BCM reset the internal timer and reactivate the inadvertent power relay.
When the inadvertent power relay is not energized, the BCM utilizes the inadvertent power
courtesy lamp supply voltage circuit to monitor for a courtesy lamp switch request signal. If a
courtesy lamp switch is activated, the BCM will receive the signal to energize the inadvertent power
relay by grounding the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Locations > Page 9908
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Locations > Page 9909
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Locations > Page 9910
Junction Block - Rear Lamps - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical Center) > Page 9913
1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relays and Modules - Power and Ground Distribution >
Relay Box > Component Information > Service and Repair > Relay Replacement (Within an Electrical Center) > Page 9914
Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Locations
Locations View
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Locations > Page
9918
Relay Box: Diagrams
Junction Block - Rear Lamps - C1
Junction Block - Rear Lamps - C2 Part 1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Locations > Page
9919
Junction Block - Rear Lamps - C2 Part 2
Junction Block - Rear Lamps - C3
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Locations > Page
9920
Junction Block - Rear Lamps - C4
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Service and Repair
> Relay Replacement (Within an Electrical Center)
Relay Box: Service and Repair Relay Replacement (Within an Electrical Center)
TOOLS REQUIRED
J 43244 Relay Puller Pliers
REMOVAL PROCEDURE
1. Remove the electrical center cover. 2. Locate the relay. Refer to Electrical Center Identification
Views to locate the electrical center where the relay exists.
IMPORTANT: Always note the orientation of the relay.
- Make sure the electrical center is secure, as not to put added stress on the wires or terminals.
3. Using the J 43244 (1) position the tool on opposing corners of the relay (2).
NOTE: Use J 43244 to pull the relay straight out from the electrical center terminals. The use of
pliers or a flat bladed tool could damage the electrical center.
4. Remove the relay (2) from the electrical center.
INSTALLATION PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Service and Repair
> Relay Replacement (Within an Electrical Center) > Page 9923
1. Install the relay (2) in the same position as removed. 2. Install the electrical center cover.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Relay Box > Component Information > Service and Repair
> Relay Replacement (Within an Electrical Center) > Page 9924
Relay Box: Service and Repair Relay Replacement (Attached to Wire Harness)
REMOVAL PROCEDURE
1. Locate the relay. Refer to the Master Electrical Component List to locate the relay in the vehicle.
2. Remove any fasteners which hold the relay in place. 3. Remove any connector position
assurance (CPA) devices or secondary locks.
IMPORTANT: Use care when removing a relay in a wiring harness when the relay is secured by
fasteners or tape.
4. Separate the relay (1) from the wire harness connector (2).
INSTALLATION PROCEDURE
1. Connect the relay (1) to the wire harness connector (2). 2. Install any connector position
assurance (CPA) devices or secondary locks. 3. Install the relay using any fasteners or tape that
originally held the relay in place.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Sensors and Switches - Power and Ground Distribution >
Power Interrupt Connector/Switch > Component Information > Description and Operation
Power Interrupt Connector/Switch: Description and Operation
BATTERY RUNDOWN PROTECTION/INADVERTENT POWER
In the event that any of the interior lamps supplied voltage by the inadvertent power relay and
ground from the courtesy lamp relay were to remain on when the ignition is OFF after a period of
20 minutes, the BCM will deactivate the inadvertent power relay turning OFF all of the lamps on
that circuit to prevent total battery discharge. Only when the ignition switch is cycled back to the
RUN position will the BCM reset the internal timer and reactivate the inadvertent power relay.
When the inadvertent power relay is not energized, the BCM utilizes the inadvertent power
courtesy lamp supply voltage circuit to monitor for a courtesy lamp switch request signal. If a
courtesy lamp switch is activated, the BCM will receive the signal to energize the inadvertent power
relay by grounding the control circuit.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set By Various Control
Modules
Wiring Harness: Customer Interest Electrical - MIL ON/DTC's Set By Various Control Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set By Various Control
Modules > Page 9937
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set By Various Control
Modules > Page 9938
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > Customer Interest: > 09-06-03-004D > Dec > 10 > Electrical - MIL ON/DTC's Set By Various Control
Modules > Page 9939
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10 > Electrical - MIL
ON/DTC's Set By Various Control Modules
Wiring Harness: All Technical Service Bulletins Electrical - MIL ON/DTC's Set By Various Control
Modules
TECHNICAL
Bulletin No.: 09-06-03-004D
Date: December 08, 2010
Subject: Intermittent No Crank/No Start, No Module Communication, MIL, Warning Lights, Vehicle
Messages or DTCs Set by Various Control Modules - Diagnosing and Repairing Fretting Corrosion
(Disconnect Affected Connector and Apply Dielectric Lubricant)
Models:
2011 and Prior GM Passenger Cars and Trucks
Attention:
This repair can be applied to ANY electrical connection including, but not limited to: lighting, body
electrical, in-line connections, powertrain control sensors, etc. DO NOT over apply lubricant to the
point where it prevents the full engagement of sealed connectors. A light coating on the terminal
surfaces is sufficient to correct the condition.
Supercede: This bulletin is being revised to update the Attention statement and add the 2011
model year. Please discard Corporate Bulletin Number 09-06-03-004C (Section 06 Engine/Propulsion System).
Condition
Some customers may comment on any of the following conditions:
- An intermittent no crank/no start
- Intermittent malfunction indicator lamp (MIL) illumination
- Intermittent service lamp illumination
- Intermittent service message(s) being displayed
The technician may determine that he is unable to duplicate the intermittent condition.
Cause
This condition may be caused by a buildup of nonconductive insulating oxidized debris known as
fretting corrosion, occurring between two electrical contact surfaces of the connection or connector.
This may be caused by any of the following conditions:
- Vibration
- Thermal cycling
- Poor connection/terminal retention
- Micro motion
- A connector, component or wiring harness not properly secured resulting in movement
On low current signal circuits this condition may cause high resistance, resulting in intermittent
connections.
On high current power circuits this condition may cause permanent increases in the resistance and
may cause a device to become inoperative.
Representative List of Control Modules and Components
The following is only a representative list of control modules and components that may be affected
by this connection or connector condition and DOES NOT include every possible module or
component for every vehicle.
- Blower Control Module
- Body Control Module (BCM)
- Communication Interface Module (CIM)
- Cooling Fan Control Module
- Electronic Brake Control Module (EBCM)
- Electronic Brake and Traction Control Module (EBTCM)
- Electronic Suspension Control (ESC) Module
- Engine Control Module (ECM)
- Heating, Ventilation and Air Conditioning (HVAC) Control Module
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10 > Electrical - MIL
ON/DTC's Set By Various Control Modules > Page 9945
- HVAC Actuator
- Inflatable Restraint Sensing and Diagnostic Module (SDM)
- Any AIR BAG module
- Seatbelt Lap Anchor Pretensioner
- Seatbelt Retractor Pretensioner
- An SIR system connection or connector condition resulting in the following DTCs being set:
B0015, B0016, B0019, B0020, B0022, or B0023
- Powertrain Control Module (PCM)
- Remote Control Door Lock Receiver (RCDLR)
- Transmission Control Module (TCM)
Correction
Important DO NOT replace the control module, wiring or component for the following conditions:
- The condition is intermittent and cannot be duplicated.
- The condition is present and by disconnecting and reconnecting the connector the condition can
no longer be duplicated.
Use the following procedure to correct the conditions listed above.
1. Install a scan tool and perform the Diagnostic System Check - Vehicle. Retrieve and record any
existing history or current DTCs from all of the
control modules (refer to SI).
‹› If any DTC(s) are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to identify the
connector(s) of the control module/component
which may be causing the condition (refer to SI).
‹› If DTCs are not set, refer to Symptoms - Vehicle to identify the connector(s) of the control
module/component which may be causing the
condition (refer to SI).
2. When identified, use the appropriate DTC Diagnostics, Symptoms, Schematics, Component
Connector End Views and Component Locator
documents to locate and disconnect the affected harness connector(s) which are causing the
condition.
Note Fretting corrosion looks like little dark smudges on electrical terminals and appear where the
actual electrical contact is being made. In less severe cases it may be unable to be seen or
identified without the use of a magnifying glass.
Important DO NOT apply an excessive amount of dielectric lubricant to the connectors as shown,
as hydrolock may result when attempting to mate the connectors. Use ONLY a clean nylon brush
that is dedicated to the repair of the conditions in this bulletin.
3. With a one-inch nylon bristle brush, apply dielectric lubricant to both the module/component side
and the harness side of the affected connector(s).
4. Reconnect the affected connector(s) and wipe away any excess lubricant that may be present.
5. Attempt to duplicate the condition by using the following information:
- DTC Diagnostic Procedure
- Circuit/System Description
- Conditions for Running the DTC
- Conditions for Setting the DTC
- Diagnostic Aids
- Circuit/System Verification
‹› If the condition cannot be duplicated, the repair is complete. ‹› If the condition can be duplicated,
then follow the appropriate DTC, Symptom or Circuit/System Testing procedure (refer to SI).
Repair Order Documentation
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10 > Electrical - MIL
ON/DTC's Set By Various Control Modules > Page 9946
Important The following information MUST be documented on the repair order. Failure to do so
may result in a chargeback.
- Customer vehicle condition.
- Was a Service Lamp or Service Message illuminated? If yes, specify which Service Lamp or
Service Message.
- Was a DTC(s) set? If yes, specify which DTC(s) were set.
- After following the procedure contained within this bulletin, could the condition be duplicated?
‹› If the condition was not duplicated, then document the affected module/component connector
name and number on the repair order.
- If the condition was duplicated after the procedure contained within this bulletin was followed, and
additional diagnosis led to the replacement of a module or component, the SI Document ID
Number MUST be written on the repair order.
Parts Information
Alternate Distributor For All of North America
Note
NyoGel(R) 760G Lubricant* is equivalent to GMSPO P/N 12377900, and P/N 10953529 (Canada),
specified for use to correct the condition in this bulletin.
*We believe this source and their products to be reliable. There may be additional manufacturers of
such products/materials. General Motors does not endorse, indicate any preference for, or assume
any responsibility for the products or material from this firm or for any such items that may be
available from other sources.
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 09-06-03-004D > Dec > 10 > Electrical - MIL
ON/DTC's Set By Various Control Modules > Page 9947
For vehicles repaired under warranty, use the appropriate/closest labor operation depending upon
the module/component connection that the dielectric lubricant was applied to refer to the table
above.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair
Wiring Harness: All Technical Service Bulletins Electrical - Information For Electrical Ground Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9952
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9953
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9954
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9955
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9956
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information
For Electrical Ground Repair > Page 9957
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 > Electrical - Instrument
Panel & General Wiring Repair
Wiring Harness: All Technical Service Bulletins Electrical - Instrument Panel & General Wiring
Repair
Bulletin No.: 06-08-45-004
Date: May 02, 2006
INFORMATION
Subject: Instrument Panel (I/P), Body and General Wiring Harness Repair
Models: 2007 and Prior GM Cars and Trucks 2003-2007 HUMMER H2 2006-2007 HUMMER H3
Important:
A part restriction has been implemented on all Body and I/P harnesses and is being administered
by the PQC. If a body or I/P harness replacement is required, it can take 12-28 weeks for a
harness to be built and delivered to a dealer. The dealer technician is expected to repair any
harness damage as the first and best choice before replacing a harness.
In an effort to standardize repair practices, General Motors is requiring that all wiring harnesses be
repaired instead of replaced. If there is a question concerning which connector and/or terminal you
are working on, refer to the information in the appropriate Connector End Views in SI. The
Instruction Manual J 38125-620, which is sent with each new update of the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal remove information.
Important:
There are some parts in the J 38125 Terminal Repair Kit (i.e. SIR connector CPAs and heat shrink
tube (used in high heat area pigtail replacement) and some TPAs that are not available from
GMSPO. It is vitally important that each update to the J 38125 Terminal Repair Kit be done as soon
as it arrives at the dealer.
Utilize the Terminal Repair Kit (J 38125) to achieve an effective wiring repair. The Terminal Repair
Kit has been an essential tool for all GM Dealers since 1987. Replacement terminals and tools for
this kit are available through SPX/Kent Moore. Refer to Corporate Bulletin Number 06-08-45-001
for more information.
The Instruction Manual J 38125-620, which is sent with each new update to the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal removal information.
U.S. Dealers Only - Training courses (including Tech Assists, Emerging Issues, Web, IDL and
Hands-on) are available through the GM Training website. Refer to Resources and then Training
Materials for a complete list of available courses.
Canadian Dealers Only - Refer to the Training section of GM infoNet for a complete list of available
courses and a copy of the J 38125 Terminal Repair Kit Instruction Manual.
Wiring repair information is also available in Service Information (SI). The Wiring Repair section
contains information for the following types of wiring repairs:
- Testing for intermittent conditions and poor conditions
- Flat wire repairs
- GMLAN wiring repairs
- High temperature wiring repairs
- Splicing copper wire using splice clips
- Splicing copper wire using splice sleeves
- Splicing twisted or shielded cable
- Splicing inline harness diodes
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 > Electrical - Instrument
Panel & General Wiring Repair > Page 9962
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair
Wiring Harness: All Technical Service Bulletins Electrical - Information For Electrical Ground Repair
INFORMATION
Bulletin No.: 10-08-45-001B
Date: October 25, 2010
Subject: Information for Electrical Ground Repair - Use New Replacement Fasteners with
Conductive Finish
Models:
2011 and Prior GM Passenger Cars and Trucks (including Saturn) 2010 and Prior HUMMER H2,
H3 2009 and Prior Saab 9-7X
Supercede: This bulletin is being revised to add the 2011 model year and update the Warranty
Information. Please discard Corporate Bulletin Number 10-08-45-001A (Section 08 - Body and
Accessories).
Electrical Ground Repair Overview
Proper electrical system function relies on secure, stable and corrosion-free electrical ground
connections. Loose, stripped, or corroded connections increase the possibility of improper system
function and loss of module communication. These conditions may also lead to unnecessary
repairs and component replacement.
In general, electrical ground connections are accomplished using one, or a combination of the
following attachment methods:
- Welded M6 stud and nut
- Welded M6 nut and bolt
- Welded M8 nut and bolt
Determine which attachment method is used and perform the appropriate or alternative repair as
described in this bulletin.
M6 Weld Stud Replacement
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. Select a location adjacent the damaged or missing M6 ground stud having 20 mm (0.79 in)
clearance behind the panel surface and 20 mm (0.79 in)
clearance surrounding the M6 conductive rivet stud flange.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
3. Drill a 10 mm (0.40 in) diameter hole through the panel.
4. Remove paint and primer from the area surrounding the 10 mm (0.40 in) hole until bare metal is
visible.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9968
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
5. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
6. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
7. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 8. Ensure the rivet stud is securely fastened, WITHOUT ANY detectable movement. 9.
Completely wrap the threads of the rivet stud with painters tape or equivalent.
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the ground wire terminal and conductive nut to maintain a secure, stable and
corrosion-free electrical ground.
10. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 11. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 12. Remove the painters tape or equivalent from the rivet
stud threads. 13. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 14. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9969
15. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 16. Install the electrical ground wire terminal to the rivet stud. 17. Select a M6
conductive nut. Refer to the Parts Information section of this bulletin. 18. Install the M6 conductive
nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in).
19. Verify proper system operation.
M6 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M6 weld nut at the electrical ground location is damaged or stripped, a M7 conductive
self-threading bolt may be used to secure the ground
wire terminal.
2. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the weld nut and allow to dry. 3. Remove any loose metal particles from the damaged
or stripped weld nut with a stiff brush. 4. Select a M7 conductive self-threading bolt. Refer to the
Parts Information section of this bulletin 5. Using a small brush, apply Dielectric Lubricant GM P/N
12377900 (Canadian P/N 10953529) to the threads of the M7 conductive self-threading
bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
6. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 7. Install the electrical ground wire terminal to the M7 conductive self-threading bolt.
8. Install the M7 conductive self-threading bolt and:
Tighten Tighten to 9 Nm (80 lb in).
9. Verify proper system operation.
M6 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the electrical ground location is accessible from both sides of the panel, a M6 conductive bolt
and a M6 conductive nut may be used to secure
the electrical ground wire terminal. Refer to the Parts Information section of this bulletin.
2. Select a location adjacent the damaged M6 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 8.5 mm (0.33 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 8.5 mm (0.33 in) hole until bare metal is visible. 6. Select a M6 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M6 conductive bolt to the ground
location.
10. Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M6 conductive nut to the bolt and:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9970
Tighten Tighten to 8 Nm (71 lb in).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is accessible from both sides of the panel, a M8
conductive bolt and a M8 conductive nut may be
used to secure the electrical ground wire terminal. Refer to the Parts Information section of this
bulletin.
2. Select a location adjacent the M8 weld nut having 20 mm (0.79 in) clearance behind the panel
surface and 20 mm (0.79 in) clearance surrounding
the new electrical ground site.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the surface
surrounding the ground location and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel. 5. Remove paint and primer from the
area surrounding the 10 mm (0.40 in) hole until bare metal is visible. 6. Select a M8 conductive
bolt. Refer to the Parts Information section of this bulletin. 7. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M8 conductive bolt.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
8. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 9. Install the electrical ground wire terminal and the M8 conductive bolt to the ground
location.
10. Select a M8 conductive nut. Refer to the Parts Information section of this bulletin. 11. Install the
M8 conductive nut to the bolt and:
Tighten Tighten to 22 Nm (16 lb ft).
Note The repair area MUST BE properly refinished to maintain a secure, stable and corrosion-free
electrical ground.
12. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 13. Verify proper system operation.
M8 Weld Nut Alternative Repair
Caution
Use only the GM-approved replacement fasteners with conductive finish for electrical ground
repair.
1. If the M8 weld nut electrical ground location is not accessible from both sides of the panel, a M6
conductive rivet stud and a M6 conductive nut
may be used to secure the electrical ground wire terminal.
2. Select a location adjacent the damaged M8 weld nut having 20 mm (0.79 in) clearance behind
the panel surface and 20 mm (0.79 in) clearance
surrounding the M6 conductive rivet stud flange.
3. Using GM approved residue-free solvent or equivalent, remove any grease from the repair site
and allow to dry.
Note Ensure 20 mm (0.79 in) clearance is maintained behind the panel to be drilled.
4. Drill a 10 mm (0.40 in) diameter hole through the panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9971
5. Remove paint and primer from the area surrounding the 10 mm (0.40 in) until bare metal is
visible.
Important The M6 conductive rivet stud as shown, can accommodate a panel thickness range of
0.7-4.2 mm (0.03-0.17 in). If there are layers of sheet metal, they should be touching without any
air gaps to ensure a good ground.
6. Select a M6 conductive rivet stud. Refer to the Parts Information section of this bulletin.
Note Use the GE-50317 rivet stud tool kit.
7. Place the M6 conductive rivet stud (1) in the 10 mm (0.40 in) hole. Assemble the rivet stud tool
(2) with the groove and flare side facing the rivet
stud, then the washer and the M6 nut (3).
8. Using a wrench on the rivet stud tool, and a socket on the M6 nut, secure the M6 conductive
rivet stud. 9. Ensure the new rivet stud is securely fastened, WITHOUT ANY detectable movement.
10. Completely wrap the threads of the rivet stud with painters tape or equivalent.
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Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9972
Note The rivet stud and surrounding panel area MUST BE properly refinished PRIOR to the
installation of the electrical ground wire terminal and conductive nut to maintain a secure, stable
and corrosion-free electrical ground.
11. Refinish the repair area using an anti-corrosion primer. Refer to Anti-Corrosion Treatment and
Repair in SI. 12. Allow the refinished repair area to cure sufficiently before removing the protective
material applied to the rivet stud threads. 13. Remove the painters tape or equivalent from the rivet
stud threads. 14. Using GM approved residue-free solvent or equivalent, thoroughly clean the rivet
stud threads to remove any adhesive and allow to dry. 15. Using a small brush, apply Dielectric
Lubricant GM P/N 12377900 (Canadian P/N 10953529) to the threads of the M6 conductive rivet
stud.
Note Fretting corrosion is a build-up of insulating, oxidized wear debris that can form when there is
a small motion between electrical contacts. The oxidized wear debris can accumulate at the
electrical contact points causing the electrical resistance across the connection to increase.
16. Carefully remove ANY corrosion or contamination that may be present on the electrical ground
wire terminal. 17. Install the electrical ground wire terminal to the M6 conductive rivet stud. 18.
Select a M6 conductive nut. Refer to the Parts Information section of this bulletin. 19. Install the M6
conductive nut to the rivet stud and:
Tighten Tighten to 8 Nm (71 lb in)
20. Verify proper system operation.
Parts Information
Warranty Information (excluding Saab Models)
For vehicles repaired under warranty, use:
Warranty Information (Saab Models)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 10-08-45-001B > Oct > 10 > Electrical - Information For
Electrical Ground Repair > Page 9973
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 > Electrical - Instrument Panel
& General Wiring Repair
Wiring Harness: All Technical Service Bulletins Electrical - Instrument Panel & General Wiring
Repair
Bulletin No.: 06-08-45-004
Date: May 02, 2006
INFORMATION
Subject: Instrument Panel (I/P), Body and General Wiring Harness Repair
Models: 2007 and Prior GM Cars and Trucks 2003-2007 HUMMER H2 2006-2007 HUMMER H3
Important:
A part restriction has been implemented on all Body and I/P harnesses and is being administered
by the PQC. If a body or I/P harness replacement is required, it can take 12-28 weeks for a
harness to be built and delivered to a dealer. The dealer technician is expected to repair any
harness damage as the first and best choice before replacing a harness.
In an effort to standardize repair practices, General Motors is requiring that all wiring harnesses be
repaired instead of replaced. If there is a question concerning which connector and/or terminal you
are working on, refer to the information in the appropriate Connector End Views in SI. The
Instruction Manual J 38125-620, which is sent with each new update of the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal remove information.
Important:
There are some parts in the J 38125 Terminal Repair Kit (i.e. SIR connector CPAs and heat shrink
tube (used in high heat area pigtail replacement) and some TPAs that are not available from
GMSPO. It is vitally important that each update to the J 38125 Terminal Repair Kit be done as soon
as it arrives at the dealer.
Utilize the Terminal Repair Kit (J 38125) to achieve an effective wiring repair. The Terminal Repair
Kit has been an essential tool for all GM Dealers since 1987. Replacement terminals and tools for
this kit are available through SPX/Kent Moore. Refer to Corporate Bulletin Number 06-08-45-001
for more information.
The Instruction Manual J 38125-620, which is sent with each new update to the J 38125 Terminal
Repair Kit, also has terminal crimping and terminal removal information.
U.S. Dealers Only - Training courses (including Tech Assists, Emerging Issues, Web, IDL and
Hands-on) are available through the GM Training website. Refer to Resources and then Training
Materials for a complete list of available courses.
Canadian Dealers Only - Refer to the Training section of GM infoNet for a complete list of available
courses and a copy of the J 38125 Terminal Repair Kit Instruction Manual.
Wiring repair information is also available in Service Information (SI). The Wiring Repair section
contains information for the following types of wiring repairs:
- Testing for intermittent conditions and poor conditions
- Flat wire repairs
- GMLAN wiring repairs
- High temperature wiring repairs
- Splicing copper wire using splice clips
- Splicing copper wire using splice sleeves
- Splicing twisted or shielded cable
- Splicing inline harness diodes
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Chevrolet Workshop Manuals > Power and Ground Distribution > Wiring Harness > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Wiring Harness: > 06-08-45-004 > May > 06 > Electrical - Instrument Panel
& General Wiring Repair > Page 9978
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications
Alignment: Technical Service Bulletins Steering/Suspension - Wheel Alignment Specifications
WARRANTY ADMINISTRATION
Bulletin No.: 05-03-07-009C
Date: December 09, 2010
Subject: Wheel Alignment Specifications, Requirements and Recommendations for GM Vehicles
Models:
2011 and Prior GM Passenger Cars and Light Duty Trucks
Supercede: This bulletin is being extensively revised to provide technicians and warranty
administrators with an all inclusive guide for wheel alignments. PLEASE FAMILIARIZE YOURSELF
WITH THESE UPDATES BEFORE PERFORMING YOUR NEXT GM WHEEL ALIGNMENT
SERVICE. Please discard Corporate Bulletin Number 05-03-07-009B (Section 03 - Suspension).
Purpose
The purpose of this bulletin is to provide retail, wholesale and fleet personnel with General Motors'
warranty service requirements and recommendations for customer concerns related to wheel
alignment. For your convenience, this bulletin updates and centralizes all of GM's Standard Wheel
Alignment Service Procedures, Policy Guidelines and bulletins on wheel alignment warranty
service.
Important PLEASE FAMILIARIZE YOURSELF WITH THESE UPDATES BEFORE PERFORMING
YOUR NEXT GM WHEEL ALIGNMENT SERVICE.
The following five (5) key steps are a summary of this bulletin and are REQUIRED in completing a
successful wheel alignment service.
1. Verify the vehicle is in an Original Equipment condition for curb weight, tires, wheels, suspension
and steering configurations. Vehicles
modified in any of these areas are not covered for wheel alignment warranty.
2. Review the customer concern relative to "Normal Operation" definitions. 3. Verify that vehicle is
within the "Mileage Policy" range. 4. Document wheel alignment warranty claims appropriately for
labor operations E2000 and E2020.
The following information must be documented or attached to the repair order:
- Customer concern in detail
- What corrected the customer concern?
- If a wheel alignment is performed:
- Consult SI for proper specifications.
- Document the "Before" AND "After" wheel alignment measurements/settings.
- Completed "Wheel Alignment Repair Order Questionnaire" (form attached to this bulletin)
5. Use the proper wheel alignment equipment (preferred with print-out capability), process and the
appropriate calibration maintenance schedules.
Important If it is determined that a wheel alignment is necessary under warranty, use the proper
labor code for the repair. E2000 for Steering Wheel Angle and/or Front Toe set or E2020 for Wheel
Alignment Check/Adjust includes Caster, Camber and Toe set (Wheel alignment labor time for
other component repairs is to be charged to the component that causes a wheel alignment
operation.).
The following flowchart is to help summarize the information detailed in this bulletin and should be
used whenever a wheel alignment is performed.
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9984
Verify Original Equipment Condition of the Vehicle
- Verify that Original Equipment Tires and Wheels or Official GM Accessory Tires and Wheels are
on the vehicle.
- Verify that aftermarket suspension "Lift" or "Lowering" Kits or other suspension alterations have
NOT been done to the vehicle.
- Check for accidental damage to the vehicle; for example, severe pothole or curb impacts, collision
damage that may have affected the wheel alignment of the vehicle; e.g., engine cradles,
suspension control arms, axles, wheels, wheel covers, tires may show evidence of damage/impact.
- Check to be sure vehicle has seen "Normal Use" rather than abuse; e.g., very aggressive driving
may show up by looking at the tires and condition of the vehicle.
- Check for other additional equipment items that may significantly affect vehicle mass such as
large tool boxes, campers, snow plow packages (without the snowplow RPO), etc., especially in
trucks and cutaway/incomplete vehicles. Significant additional mass can affect trim height and
wheel alignment of the vehicle and may necessitate a customer pay wheel alignment when placed
semi-permanently in the vehicle (Upfitter instructions are to realign the vehicle after placement of
these types of items. (This typically applies to trucks and incomplete vehicles that can be upfit with
equipment such as the above.)
Customer Concerns, "Normal Operation" Conditions and "Mileage Policy"
Possible Concerns
The following are typical conditions that may require wheel alignment warranty service:
1. Lead/Pull: defined as "at a constant highway speed on a typical straight road, the amount of
effort required at the steering wheel to maintain the
vehicle's straight heading."
Important Please evaluate for the condition with hands-on the steering wheel. Follow the "Vehicle
Leads/Pulls" diagnostic tree located in SI to determine the cause of a lead/pull concern. Lead/Pull
concerns can be due to road crown or road slope, tires, wheel alignment or even in rare
circumstances a steering gear issue. Lead/pull concerns due to road crown are considered
"Normal Operation" and are NOT a warrantable condition -- the customer should be advised that
this is "Normal Operation."
Important Some customers may comment on a "Lead/Pull" when they hold the steering wheel in a
level condition. If so, this is more likely a "steering wheel angle" concern because the customer is
"steering" the vehicle to obtain a "level" steering wheel.
2. Steering wheel angle to the left or right (counter-clockwise or clockwise, respectively): Defined
as the steering wheel angle (clocking)
deviation from "level" while maintaining a straight heading on a typical straight road.
3. Irregular or Premature tire wear: Slight to very slight "feathering" or "edge" wear on the
shoulders of tires is NOT considered unusual and
should even out with a tire rotation; if the customer is concerned about a "feathering" condition of
the tires, the customer could be advised to rotate the tires earlier than the next scheduled
mileage/maintenance interval (but no later than the next interval). Be sure to understand the
customer's driving habits as this will also heavily influence the tire wear performance; tire wear from
aggressive or abusive driving habits is NOT a warrantable condition.
Important Slight or mild feathering, cupping, edge or heel/toe wear of tire tread shoulders is
"normal" and can show up very early in a tire/vehicle service mileage; in fact, some new tires can
show evidence of feathering from the factory. These issues do NOT affect the overall performance
and tread life of the tire. Dealer personnel should always check the customer's maintenance
records to ensure that tire inflation pressure is being maintained to placard and that the tires are
being rotated (modified-X pattern) at the proper mileage intervals. Wheel alignments are NOT to be
performed for the types of "Normal" Tire Feathering shown in Figures 1-4 below.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9985
Figure 1: Full Tread View - "NORMAL" Tire "Feathering" Wear on the Shoulder/Adjacent/Center
Ribs
Figure 2: Tire Shoulder View Example 1 - "NORMAL" Tire "Feathering" Wear on the Shoulder
Figure 3: Tire Shoulder View Example 2 - "NORMAL" Tire "Feathering" Wear
Figure 4: Detail Side View of Tire Shoulder Area - "NORMAL" Tire "Feathering" Wear
Important When a wheel alignment is deemed necessary for tire wear, be sure to document on the
repair order, in as much detail as possible, the severity and type of tire wear (e.g., severe center
wear or severe inside or outside shoulder wear) and the position of the tire on the vehicle (RF, LF,
LR, RR). Please note the customer's concern with the wear such as, noise, appearance, wear life,
etc. A field product report with pictures of the tire wear condition is recommended. Refer to
Corporate Bulletin Number 02-00-89-002J and #07-00-89-036C.
4. Other repairs that affect wheel alignment; e.g., certain component replacement such as
suspension control arm replacement, engine cradle
adjustment/replace, steering gear replacement, steering tie rod replace, suspension strut/shock,
steering knuckle, etc. may require a wheel alignment.
Important If other components or repairs are identified as affecting the wheel alignment, policy calls
for the wheel alignment labor time to be charged to the replaced/repaired component's labor
operation time rather than the wheel alignment labor operations.
Important Vibration type customer concerns are generally NOT due to wheel alignment except in
the rare cases; e.g., extreme diagonal wear across the tread. In general, wheel alignments are
NOT to be performed as an investigation/correction for vibration concerns.
"Normal Operation" Conditions
Vehicle Lead/Pull Due to Road Crown or Slope:
As part of "Normal Operation," vehicles will follow side-to-side or left to right road crown or slope.
Be sure to verify from the customer the types of roads they are driving as they may not recognize
the influence of road crown on vehicle lead/pull and steering wheel angle. If a vehicle requires
significant steering effort to prevent it from "climbing" the road crown there may be an issue to be
looked into further.
Important
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9986
A wheel alignment will generally NOT correct vehicles that follow the road crown since this is within
"Normal Operation."
Mileage Policy
The following mileage policy applies for E2020 and E2000 labor operations: Note
Wheel Alignment is NOT covered under the New Vehicle Limited Warranty for Express and Savana
Cutaway vehicles as these vehicles require Upfitters to set the wheel alignment after completing
the vehicles.
- 0-800 km (0-500 mi): E2000/E2020 claims ONLY allowed with Call Center Authorization. Due to
the tie down during shipping, the vehicle's suspension requires some time to reach normal
operating position. For this reason, new vehicles are generally NOT to be aligned until they have
accumulated at least 800 km (500 mi). A field product report should accompany any claim within
this mileage range.
- 801-12,000 km (501-7,500 mi):
- If a vehicle came from the factory with incorrect alignment settings, any resulting off-angle
steering wheel, lead/pull characteristics or the rare occurrence of excessive tire wear would be
apparent early in the life of the vehicle. The following policy applies:
- Vehicles 100% Factory Set/Measured for Caster/Camber/Toe - Escalade/ESV/EXT,
Tahoe/Suburban, Yukon/XL/Denali, Silverado/Sierra, Express/Savana, Corvette and
Colorado/Canyon: E2000/E2020 Claims: Call Center Authorization Required
- All Vehicles NOT 100% Factory Set/Measured for Caster/Camber/Toe as noted above:
E2000/E2020 Claims: Dealer Service Manager Authorization Required
- 12,001 km and beyond (7,501 miles and beyond): During this period, customers are responsible
for the wheel alignment expense or dealers may provide on a case-by case basis a one-time
customer enthusiasm claim up to 16,000 km (10,000 mi). In the event that a defective component
required the use of the subject labor operations, the identified defective component labor operation
will include the appropriate labor time for a wheel alignment as an add condition to the component
repair.
Important Only one wheel alignment labor operation claim (E2000 or E2020) may be used per VIN.
Warranty Documentation Requirements
When a wheel alignment service has been deemed necessary, the following items will need to be
clearly documented on/with the repair order:
- Customer concern in detail
- What corrected the customer concern?
- If a wheel alignment is performed:
- Consult SI for proper specifications.
- Document the "Before" AND "After" wheel alignment measurements/settings.
- Completed "Wheel Alignment Repair Order Questionnaire" (form attached to this bulletin)
1. Document the customer concern in as much detail as possible on the repair order and in the
warranty administration system. Preferred examples:
- Steering wheel is off angle in the counterclockwise direction by approximately x degrees or
clocking position.
- Vehicle lead/pulls to the right at approximately x-y mph. Vehicle will climb the road crown. Severe,
Moderate or Slight.
- RF and LF tires are wearing on the outside shoulders with severe feathering.
Important In the event of a lead/pull or steering wheel angle concern, please note the direction of
lead/pull (left or right) or direction of steering wheel angle (clockwise or counterclockwise) on the
repair order and within the warranty claim verbatim.
Important In the event of a tire wear concern, please note the position on the vehicle and where the
wear is occurring on the tire; i.e., the RF tire is wearing on the inside shoulder.
2. Document the technician's findings on cause and correction of the issue. Examples:
- Reset LF toe from 0.45 degrees to 0.10 degrees and RF toe from -0.25 degrees to 0.10 degrees
to correct the steering wheel angle from 5 degrees counterclockwise to 0 degrees.
- Reset LF camber from 0.25 degrees to -0.05 degrees to correct the cross-camber condition of
+0.30 degrees to 0.00 degrees on the vehicle.
- Front Sum toe was found to be 0.50 degrees, reset to 0.20 degrees.
3. Print-out the "Before" and "After" wheel alignment measurements/settings and attach them to the
Repair Order or if print-out capability is not
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9987
available, measurements may also be clearly and legibly handwritten into the Wheel Alignment
Repair Order Questionnaire attached to this bulletin.
4. Attach the Wheel Alignment Repair Order Questionnaire below along with the print-out of
"Before" and "After" wheel alignment measurements to
the Repair Order and retain for use by GM.
Wheel Alignment Equipment and Process
Wheel alignments must be performed with a quality machine that will give accurate results when
performing checks. "External Reference" (image-based camera technology) is preferred. Please
refer to Corporate Bulletin Number 05-00-89-029B: General Motors Dealership Critical Equipment
Requirements and Recommendations.
Requirements:
- Computerized four wheel alignment system.
- Computer capable of printing before and after alignment reports.
- Computer capable of time and date stamp printout.
- Racking system must have jacking capability
- Racking system must be capable of level to 1.6 mm (1/16 in)
- Appropriate wheel stops and safety certification
- Built-in turn plates and slip plates
- Wheel clamps capable of attaching to 20" or larger wheels
- Racking capable of accepting any GM passenger car or light duty truck
- Operator properly trained and ASE-certified (U.S. only) in wheel alignment
Recommendations:
Racking should have front and rear jacking capability.
Equipment Maintenance and Calibration:
Alignment machines must be regularly calibrated in order to give correct information. Most
manufacturers recommend the following:
- Alignment machines with "internal reference" sensors should be checked (and calibrated, if
necessary) every six months.
- Alignment machines with "external reference" (image-based camera technology) should be
checked (and calibrated, if necessary) once a year.
- Racks must be kept level to within 1.6 mm (1/16 in).
- If any instrument that is part of the alignment machine is dropped or damaged in some way,
check the calibration immediately.
Check with the manufacturer of your specific equipment for their recommended service/calibration
schedule.
Wheel Alignment Process
When performing wheel alignment measurement and/or adjustment, the following steps should be
taken:
Preliminary Steps:
1. Verify that the vehicle has a full tank of fuel (compensate as necessary). 2. Inspect the wheels
and the tires for damage. 3. Inspect the tires for the proper inflation and irregular tire wear. 4.
Inspect the wheel bearings for excessive play. 5. Inspect all suspension and steering parts for
looseness, wear, or damage. 6. Inspect the steering wheel for excessive drag or poor return due to
stiff or rusted linkage or suspension components. 7. Inspect the vehicle trim height. 8. Compensate
for frame angle on targeted vehicles (refer to Wheel Alignment Specifications in SI).
Satisfactory vehicle operation may occur over a wide range of alignment angles. However, if the
wheel alignment angles are not within the range of specifications, adjust the wheel alignment to the
specifications. Refer to Wheel Alignment Specifications in SI. Give consideration to excess loads,
such as tool boxes, sample cases, etc. Follow the wheel alignment equipment manufacturer's
instructions.
Measure/Adjust:
Important Prior to making any adjustments to wheel alignment on a vehicle, technicians must verify
that the wheel alignment specifications loaded into their wheel alignment machine are up-to-date
by comparing these to the wheel alignment specifications for the appropriate model and model year
in SI. Using incorrect and/or outdated specifications may result in unnecessary adjustments,
irregular and/or premature tire wear and repeat customer concerns
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9988
Important When performing adjustments to vehicles requiring a 4-wheel alignment, set the rear
wheel alignment angles first in order to obtain proper front wheel alignment angles.
Perform the following steps in order to measure the front and rear alignment angles:
1. Install the alignment equipment according to the manufacturer's instructions. 2. Jounce the front
and the rear bumpers 3 times prior to checking the wheel alignment. 3. Measure the alignment
angles and record the readings.
If necessary, adjust the wheel alignment to vehicle specification and record the before and after
measurements. Refer to Wheel Alignment Specifications in SI.
Important Technicians must refer to SI for the correct wheel alignment specifications. SI is the only
source of GM wheel alignment specifications that is kept up-to-date throughout the year.
Test drive vehicle to ensure proper repair.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9989
Frame Angle Measurement (Express / Savana Only) ........
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9990
What corrected the customer concern and was the repair verified?
Please Explain: .............
Disclaimer
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Technical Service Bulletins >
Steering/Suspension - Wheel Alignment Specifications > Page 9991
Alignment: Technical Service Bulletins Steering/Suspension - Revised Caster/Camber Adjustment
Info - Revised Front Caster and Camber Adjustment Procedure # 02-03-07-002A - (Mar 24, 2005)
Models: 1999-2000 Cadillac Escalade 2002-2005 Cadillac Escalade, Escalade EXT 1999-2005
Chevrolet Express, Silverado, Suburban, Tahoe 2002-2005 Chevrolet Avalanche 1999 GMC
Suburban 1999-2005 GMC Savana, Sierra, Yukon, Yukon XL, Yukon XL Denali
This bulletin is being revised to add model years and clarify the information. Please discard
Corporate Bulletin Number 02-03-07-002 (Section 03 - Suspension).
When performing a wheel alignment on any of the above vehicles, please refer to the Front Caster
and Camber Adjustment Procedure in SI before contacting the GM Technical Assistance Center
(TAC) with issues concerning adjustments, caster out-of-spec, etc.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Ride/Trim
Height Inspection Procedure
Alignment: Specifications Ride/Trim Height Inspection Procedure
Trim Height Inspection Procedure
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights
can cause bottoming out over bumps, damage to the suspension components and symptoms
similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns
and before checking the wheel alignment. Perform the following before measuring the trim heights:
1. Set the tire pressures to the pressure shown on the certification label. 2. Check the fuel level.
Add additional weight if necessary to simulate a full tank. 3. Make sure the rear compartment is
empty except for the spare tire. 4. Make sure the vehicle is on a level surface, such as an
alignment rack. 5. Close the doors. 6. Close the hood. 7. All dimensions are measured vertical to
the ground. Trim heights should be within 13 mm (0.5 inch) to be considered correct.
Z Height Measurement
Important: K models only the Z height must be adjusted before the alignment.
The Z height dimension measurement determines the proper ride height for the front end of the
vehicle. Vehicles equipped with torsion bars use an adjusting arm in order to adjust the Z height
dimension. Vehicles without torsion bars have no adjustment and could require replacement of
suspension components. 1. Lift the front bumper of the vehicle up about 38 mm (1.5 inch). 2.
Gently remove your hands. 3. Allow the vehicle to settle into position. 4. Repeat this jouncing
operation 2 more times for a total of 3 times.
5. Measure from the pivot bolt center line (3) down to the lower corner (5) of the lower ball joint (1)
in order to obtain the Z height measurement (4). 6. Push the front bumper of the vehicle down
about 38 mm (1.5 inch). 7. Gently remove your hands. 8. Allow the vehicle to rise. 9. Repeat the
operation for a total of 3 times.
10. Measure the Z dimension. 11. The true Z height dimension number is the average of the high
and the low measurements.
Z Height Adjustment
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Ride/Trim
Height Inspection Procedure > Page 9994
1. For vehicles equipped with a torsion bar suspension turn the bolt (1) that contacts the torsion
arm clockwise to raise the and counterclockwise to
lower the height adjustment. One revolution of the bolt (1) into the nut increases the Z height by
approximately 6.0 mm (0.2 inch).
2. For vehicles without torsion bars, replace damaged or worn components as necessary.
D Height Measurement
The D height dimension measurement determines the proper rear end ride height. There is no
adjustment procedure. Repair may require replacement of suspension components. 1. With the
vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 inch). 2. Gently remove your
hands. Allow the vehicle to settle into position. 3. Repeat the jouncing operation 2 more times for a
total of 3 times.
4. Measure the D height by measuring the distance between the bumper bracket and the top of the
rear axle tube. 5. Push the rear bumper downward to 38 mm (1.5 inch). 6. Gently remove your
hands. Allow the vehicle to settle into position. 7. Repeat the jouncing operation 2 more times for a
total of 3 times. 8. Measure the D height dimension. 9. The true D height dimension number is the
average of the high and the low measurements.
10. If these measurements are out of specifications, inspect for the following conditions:
^ Sagging front suspension
^ Sagging rear leaf/coil springs
^ Worn rear suspension components, such as leaf spring bushings
^ Improper tire inflation
^ Improper weight distribution
^ Collision damage
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Height Inspection Procedure > Page 9995
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Ride/Trim
Height Inspection Procedure > Page 9996
Alignment: Specifications Wheel Alignment Specifications
Alignment
Wheel Alignment Specifications
Fastener Tightening Specifications
Trim Height Specifications
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Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Page 9997
Alignment: Description and Operation
Caster Description
Caster is the tilting of the uppermost point of the steering axis either forward or backward, when
viewed from the side of the vehicle. A backward tilt is positive (+) and a forward tilt is negative (-).
Caster influences directional control of the steering but does not affect the tire wear and is not
adjustable on this vehicle. Caster is affected by the vehicle height, therefore it is important to keep
the body at its designed height. Overloading the vehicle or a weak or sagging rear spring will affect
caster. When the rear of the vehicle is lower than its designated trim height, the front suspension
moves to a more positive caster. If the rear of the vehicle is higher than its designated trim height,
the front suspension moves to a less positive caster. With too little positive caster, steering may be
touchy at high speed and wheel returnability may be diminished when coming out of a turn. If one
wheel has more positive caster than the other, that wheel will pull toward the center of the vehicle.
This condition will cause the vehicle to pull or lead to the side with the least amount of positive
caster.
Camber Description
Camber is the tilting of the wheels from the vertical when viewed from the front of the vehicle.
When the wheels tilt outward at the top, the camber is positive (+). When the wheel tilts inward at
the top, the camber is negative (-). The amount of tilt is measured in degrees from the vertical.
Camber settings influence the directional control and the tire wear. Too much positive camber will
result in premature wear on the outside of the tire and cause excessive wear on the suspension
parts. Too much negative camber will result in premature wear on the inside of the tire and cause
excessive wear on the suspension parts. Unequal side-to-side camber of 1 degree or more will
cause the vehicle to pull or lead to the side with the most positive camber.
Toe Description
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Page 9998
Toe is a measurement of how much the front and/or rear wheels are turned in or out from a
straight-ahead position. When the wheels are turned in, toe is positive (+). When the wheels are
turned out, toe is negative (-). The actual amount of toe is normally only a fraction of a degree. The
purpose of toe is to ensure that the wheels roll parallel. Toe also offsets the small deflections of the
wheel support system that occur when the vehicle is rolling forward. In other words, with the vehicle
standing still and the wheels set with toe-in, the wheels tend to roll parallel on the road when the
vehicle is moving. Improper toe adjustment will cause premature tire wear and cause steering
instability.
Setback Description
Setback applies to both the front and the rear wheels. Setback is the amount that one wheel may
be aligned behind the other wheel. Setback may be the result of a road hazard or a collision. The
first clue is a caster difference from side-to-side of more than 1 degree.
Thrust Angles Description
The front wheels aim or steer the vehicle. The rear wheels control tracking. This tracking action
relates to the thrust angle (3). The thrust angle is the path that the rear wheels take. Ideally, the
thrust angle is geometrically aligned with the body centerline (2). In the illustration, toe-in is shown
on the left rear wheel, moving the thrust line (1) off center. The resulting deviation from the
centerline is the thrust angle.
Lead/Pull Description
Lead/pull is the deviation of the vehicle from a straight path, on a level road, without hand pressure
on the steering wheel. Lead/pull is usually caused by the following factors: ^
Tire construction
^ Uneven brake adjustment
^ Wheel alignment
The way in which a tire is built may produce lead/pull. The rear tires will not cause lead.
Memory Steer Description
Memory steer is when the vehicle wants to lead or pull in the direction the driver previously turned
the vehicle. Additionally, after turning in the opposite direction, the vehicle will want to lead or pull in
that direction.
Wander Description
Wander is the undesired drifting or deviation of a vehicle to either side from a straight path with
hand pressure on the steering wheel. Wander is a symptom of the vehicle's sensitivity to external
disturbances, such as road crown and crosswind, and accentuated by poor on-center steering feel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Specifications > Page 9999
Scrub Radius Description
Ideally, the scrub radius is as small as possible. Normally, the SAI angle and the centerline of the
tire and the wheel intersect below the road surface, causing a positive scrub radius. With struts, the
SAI angle is much larger than the long arm/short arm type of suspension. This allows the SAI angle
to intersect the camber angle above the road surface, forming a negative scrub radius. The smaller
the scrub radius, the better the directional stability. Installing aftermarket wheels that have
additional offset will dramatically increase the scrub radius. The newly installed wheels may cause
the centerline of the tires to move further away from the spindle. This will increase the scrub radius.
A large amount of scrub radius can cause severe shimmy after hitting a bump. Four-wheel drive
vehicles with large tires use a steering damper to compensate for an increased scrub radius. Scrub
radius is not directly measurable by the conventional methods. Scrub radius is projected
geometrically by engineers during the design phase of the suspension.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection
Alignment: Service and Repair Trim Height Inspection
Trim Height Inspection Procedure
Trim Height Measurements
Trim height is a predetermined measurement relating to vehicle ride height. Incorrect trim heights
can cause bottoming out over bumps, damage to the suspension components and symptoms
similar to wheel alignment problems. Check the trim heights when diagnosing suspension concerns
and before checking the wheel alignment. Perform the following before measuring the trim heights:
1. Set the tire pressures to the pressure shown on the certification label. 2. Check the fuel level.
Add additional weight if necessary to simulate a full tank. 3. Make sure the rear compartment is
empty except for the spare tire. 4. Make sure the vehicle is on a level surface, such as an
alignment rack. 5. Close the doors. 6. Close the hood. 7. All dimensions are measured vertical to
the ground. Trim heights should be within 13 mm (0.5 inch) to be considered correct.
Z Height Measurement
Important: K models only the Z height must be adjusted before the alignment.
The Z height dimension measurement determines the proper ride height for the front end of the
vehicle. Vehicles equipped with torsion bars use an adjusting arm in order to adjust the Z height
dimension. Vehicles without torsion bars have no adjustment and could require replacement of
suspension components. 1. Lift the front bumper of the vehicle up about 38 mm (1.5 inch). 2.
Gently remove your hands. 3. Allow the vehicle to settle into position. 4. Repeat this jouncing
operation 2 more times for a total of 3 times.
5. Measure from the pivot bolt center line (3) down to the lower corner (5) of the lower ball joint (1)
in order to obtain the Z height measurement (4). 6. Push the front bumper of the vehicle down
about 38 mm (1.5 inch). 7. Gently remove your hands. 8. Allow the vehicle to rise. 9. Repeat the
operation for a total of 3 times.
10. Measure the Z dimension. 11. The true Z height dimension number is the average of the high
and the low measurements.
Z Height Adjustment
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection > Page 10002
1. For vehicles equipped with a torsion bar suspension turn the bolt (1) that contacts the torsion
arm clockwise to raise the and counterclockwise to
lower the height adjustment. One revolution of the bolt (1) into the nut increases the Z height by
approximately 6.0 mm (0.2 inch).
2. For vehicles without torsion bars, replace damaged or worn components as necessary.
D Height Measurement
The D height dimension measurement determines the proper rear end ride height. There is no
adjustment procedure. Repair may require replacement of suspension components. 1. With the
vehicle on a flat surface, lift upward on the rear bumper 38 mm (1.5 inch). 2. Gently remove your
hands. Allow the vehicle to settle into position. 3. Repeat the jouncing operation 2 more times for a
total of 3 times.
4. Measure the D height by measuring the distance between the bumper bracket and the top of the
rear axle tube. 5. Push the rear bumper downward to 38 mm (1.5 inch). 6. Gently remove your
hands. Allow the vehicle to settle into position. 7. Repeat the jouncing operation 2 more times for a
total of 3 times. 8. Measure the D height dimension. 9. The true D height dimension number is the
average of the high and the low measurements.
10. If these measurements are out of specifications, inspect for the following conditions:
^ Sagging front suspension
^ Sagging rear leaf/coil springs
^ Worn rear suspension components, such as leaf spring bushings
^ Improper tire inflation
^ Improper weight distribution
^ Collision damage
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection > Page 10003
Alignment: Service and Repair Measuring Wheel Alignment
Measuring Wheel Alignment
Steering and vibration complaints are not always the result of improper alignment. One possible
cause is wheel and tire imbalance. Another possibility is tire lead due to worn or improperly
manufactured tires. Lead is the vehicle deviation from a straight path on a level road without
pressure on the steering wheel. Refer to Radial Tire Lead/Pull Correction in order to determine if
the vehicle has a tire lead problem. Before performing any adjustment affecting wheel alignment,
perform the following inspections and adjustments in order to ensure correct alignment readings: ^
Inspect the tires for the proper inflation and irregular tire wear. Refer to Tire Inflation Pressure
Specifications and Tire Diagnosis - Irregular or Premature Wear.
^ Inspect the runout of the wheels and the tires.
^ Inspect the wheel bearings for backlash and excessive play.
^ Inspect the ball joints and tie rod ends for looseness or wear. Inspect the control arms and
stabilizer shaft for looseness or wear.
^ Inspect the steering gear for looseness at the frame.
^ Inspect the struts/shock absorbers for wear, leaks, and any noticeable noises.
^ Inspect the vehicle trim height.
^ Inspect the steering wheel for excessive drag or poor return due to stiff or rusted linkage or
suspension components.
^ Inspect the fuel level. The fuel tank should be full or the vehicle should have a compensating load
added.
Give consideration to excess loads, such as tool boxes, sample cases, etc. If normally carried in
the vehicle, these items should remain in the vehicle during alignment adjustments. Give
consideration also to the condition of the equipment being used for the alignment. Follow the
equipment manufacturer's instructions. Satisfactory vehicle operation may occur over a wide range
of alignment settings. However, if the setting exceeds the service allowable specifications, correct
the alignment to the service preferred specifications. Perform the following steps in order to
measure the front and rear alignment angles: 1. Install the alignment equipment according to the
manufacturer's instructions. 2. Jounce the front and the rear bumpers 3 times prior to checking the
wheel alignment. 3. Measure the alignment angles and record the readings.
Important: When performing adjustments to vehicles requiring a 4-wheel alignment, set the rear
wheel alignment angles first in order to obtain proper front alignment angles.
4. Adjust alignment angles to vehicle specification, if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection > Page 10004
Alignment: Service and Repair Front Wheel Alignment
Front Caster and Camber Adjustment
Front Caster and Camber Adjustment
1. Determine if the vehicle is relative to frame or relative to ground. If caster is relative to frame, the
caster values must be compensated for the
measured frame angle. To determine the frame angle use a digital protractor or equivalent.
2. Frame angle is positive when higher in the rear. Measure both sides of the frame and take an
average from those measurements. Then add the
average frame angle to the caster reading obtained in step 5 of this procedure when making
adjustments.
3. Frame angle is negative when lower in the rear. Measure both sides of the frame and take an
average from the measurements. Then subtract the
average frame angle from the caster reading obtained in step 5 of this procedure when making
adjustments.
4. The caster and camber adjustments are made by rotating the offset cam bolt and the cam in the
slotted frame bracket in order to reposition the
control arm.
Important: Before adjusting the caster and camber angles, jounce the front bumper three times to
allow the vehicle to return to normal height. Measure and adjust the caster and the camber with the
vehicle at curb height. The front suspension Z dimension is indicated in Trim Heights.
5. For an accurate reading, do not push or pull on the tires during the alignment process.
6. Determine the caster angle (2). Be sure to compensate for frame angle where required.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection > Page 10005
7. Determine the positive camber (2) or negative camber (3) angle.
8. Remove the pinned adjusting cam insert. Do not reinstall the cam insert. 9. Loosen the upper
control arm cam adjustment bolts.
Notice: Refer to Fastener Notice in Service Precautions.
10. Adjust the caster and the camber angle by turning the cam bolts until the specifications have
been met.
When the adjustments are complete, hold the cam bolt head in order to ensure the cam bolt
position does not change while tightening the nut. Tighten the cam nuts to 190 Nm (140 ft. lbs.).
11. Verify that the caster and the camber are still within specifications. When the caster and
camber are within specifications, adjust the toe.
Front Wheel Toe Adjustment
Front Toe Adjustment
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Alignment > System Information > Service and Repair > Trim
Height Inspection > Page 10006
1. Loosen the jam nut on the tie rod (2). 2. Rotate the inner tie rod (1) to the required toe
specification setting.
Notice: Refer to Fastener Notice in Service Precautions.
3. Tighten the jam nut on the tie rod.
Tighten the tie rod jam to 68 Nm (50 ft. lbs.).
4. Check the toe seeing after tightening. 5. Re-adjust the toe setting if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Specifications
Suspension Control Module: Specifications
Electronic Suspension Control Module to Bracket
.............................................................................................................................. 1.6 Nm (14 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 10014
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 10015
Suspension Control Module: Diagrams C3
Suspension Control Module - C3
Part 1 of 2
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Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > C1 > Page 10016
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Suspension > Suspension Control Module > Component Information > Diagrams > Page 10017
Suspension Control Module: Service and Repair
Electronic Suspension Control Module Replacement (Tahoe/Yukon/Escalade)
Removal Procedure
1. Remove the right side interior trim panel. 2. Disconnect the electrical connectors from the
module.
3. Remove the screw. 4. Slide the module from the bracket and remove the module from the
vehicle.
Installation Procedure
1. Install the module to the vehicle by sliding the module into the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the screw.
Tighten the screw to 1.6 Nm (14 inch lbs.).
3. Connect the electrical connectors to the module. 4. If you are replacing the module you must
recalibrate the module by performing the following procedure:
^ Connect the scan tool to the Data Line Connector (DLC).
^ Turn the ignition ON with the engine OFF.
^ Proceed per the instructions on the scan tool readout.
5. Install the right side interior trim panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Relays and Modules - Steering and Suspension > Relays and
Modules - Wheels and Tires > Tire Pressure Monitor Receiver / Transponder > Component Information > Technical Service
Bulletins > Tire Monitor System - TPM Sensor Information
Tire Pressure Monitor Receiver / Transponder: Technical Service Bulletins Tire Monitor System TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Angle Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position
Sensor - W/ RTD > Page 10030
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Page 10031
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Angle Sensor > Component Information > Diagrams > Page 10032
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures
Steering Column Position Sensor: Technical Service Bulletins Steering - Revised Service
Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10037
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10038
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10039
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10040
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10041
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10042
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10043
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins >
Steering - Revised Service Procedures > Page 10044
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
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Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10045
Steering Column Position Sensor: Service and Repair
This article has been updated with TSB# 03-02-36-002
REVISED STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT PROCEDURE AND STEERING WHEEL POSITION SENSOR CENTERING
PROCEDURE
STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. 2. Remove the steering column from the vehicle.
3. Remove the following from the steering shaft:
A. steering shaft seal (7) B. sensor retainer (6) C. steering wheel position sensor (5), refer to
Steering Wheel Position Sensor Centering. D. two lower spring retainers (4) E. lower bearing
spring (3) F. lower bearing seat (2) G. adapter and bearing assembly (1)
INSTALLATION PROCEDURE
1. Install the following onto the steering shaft:
A. adapter and bearing assembly (1) B. lower bearing seat (2) C. lower bearing spring (3) D. 2
lower spring retainers (4) E. steering wheel position sensor (5) refer to Steering Wheel Position
Sensor Centering. F. sensor retainer (6) G. steering shaft seal (7) H. Enable the SIR system.
2. Install the steering column to the vehicle. 3. Enable the SIR system.
STEERING WHEEL POSITION SENSOR CENTERING
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10046
IMPORTANT: Identify the type of steering wheel position sensor from the illustrations below
BEFORE removing the sensor from the steering column. Once you have identified the steering
wheel position sensor, follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
IMPORTANT: If reusing the existing sensor, you do not have to align the sensor before removal.
Centering is not required when it is time to reinstall.
3. Remove the connector from the sensor. 4. Remove the sensor (1) from the adapter and bearing
assembly. 5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
IMPORTANT: If reusing the existing sensor, you must make an alignment mark on the rotor flange
cuff (3) before removing the sensor. Failure to do so will cause misalignment when installing the
sensor. A new sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3). 8. Remove the connector from the
sensor. 9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10047
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor. 13. Remove the sensor from the adapter and bearing
assembly. 14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor. 17. Remove the sensor clip from the sensor. 18.
Remove the sensor from the adapter and bearing assembly. 19. To install the sensor, proceed to
step 13 in the installation section.
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor. 22. Remove the sensor from the adapter and bearing
assembly. 23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10048
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor. 26. Remove the sensor from the adapter and bearing
assembly. 27. To install the sensor, proceed to step 21 in the installation section.
INSTALLATION PROCEDURE
IMPORTANT: If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of
the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 4. Install the connector to the sensor. 5. From the technicians point
of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 8. Install the connector to the sensor.
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10049
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 20. Install the connector to the sensor.
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and Switches - Steering > Steering Column Position Sensor > Component Information > Technical Service Bulletins > Page
10050
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 24. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Specifications
Ride Height Sensor: Specifications
Front Position Sensor Link Bracket Bolt
................................................................................................................................................. 9 Nm
(80 inch lbs.) Front Position Sensor Mounting Bolt
.................................................................................................................................................. 12 Nm
(106 inch lbs.) Rear Position Sensor Link Bracket Bolt
................................................................................................................................................... 25
Nm (18 ft. lbs.) Rear Position Sensor Mounting Bolt
................................................................................................................................................... 12
Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page
10057
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page
10058
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page
10059
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Service and Repair >
Front Position Sensor Link Assembly Replacement - Electronic Suspension
Ride Height Sensor: Service and Repair Front Position Sensor Link Assembly Replacement Electronic Suspension
Front Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the mounting bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the mounting bracket.
2. Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Ride Height Sensor, Suspension Control > Component Information > Service and Repair >
Front Position Sensor Link Assembly Replacement - Electronic Suspension > Page 10062
Ride Height Sensor: Service and Repair Rear Position Sensor Link Assembly Replacement Electronic Suspension
Rear Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the frame bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the frame bracket. 2.
Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Steering Angle Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel
Speed/Position Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Steering Wheel
Speed/Position Sensor - W/ RTD > Page 10068
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Page 10069
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Steering Angle Sensor > Component Information > Diagrams > Page 10070
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
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Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Suspension > Suspension Control Pressure Sensor/Switch > Component Information > Service and Repair
Suspension Control Pressure Sensor/Switch: Service and Repair
"For information regarding this component please refer to air dryer suspension control service and
repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Sensors and Switches - Steering and Suspension > Sensors
and Switches - Wheels and Tires > Tire Pressure Sensor > Component Information > Technical Service Bulletins > Tire
Monitor System - TPM Sensor Information
Tire Pressure Sensor: Technical Service Bulletins Tire Monitor System - TPM Sensor Information
INFORMATION
Bulletin No.: 08-03-16-003
Date: May 12, 2008
Subject: Warranty Reduction - Transfer of Tire Pressure Monitoring (TPM) Sensors to
Replacement Wheels and Allowable TPM Sensor Replacements
Models: 2000-2009 GM Passenger Cars and Light Duty Trucks (including Saturn) 2003-2009
HUMMER H2 2006-2009 HUMMER H3 2005-2009 Saab 9-7x
with On-Wheel TPM Sensors
TPM Sensor / Wheel Warranty Reviews
During the last warranty review period it was noted that wheels being returned under the GM New
Vehicle Warranty were being shipped back to General Motors with the TPM sensor still attached to
the wheel. Return rates ran as high as 60% with the TPM sensors still attached. Operational TPM
sensors should not be returned to GM and are to be transferred to replacement wheels if they
become necessary.
Important:
Operational TPM Sensors that are returned under warranty to General Motors will be charged back
to the dealer.Sensors have a 10 year /150,000 mile (240,000 km) battery life, and should be
transferred if one or more wheels are replaced.
TPM Valve Stem / Grommet (0-ring) Replacement
When the TPM sensors are transferred to new wheels you should replace the component used to
seal the TPM sensor stem to the wheel. On sensors with an aluminum stem and visible nut on the
outside of the wheel a replacement grommet (0-ring) should be used to assure a proper seal. The
sensor retaining nut (except Aveo) should be tightened to 7 N.m (62 lb in) for all vehicles except
Pontiac Vibe (4.0 N.m (35.4 lb in)).
Important:
^ DO NOT overtorque the retaining nut.
Notice:
^ Factory installed TPM Sensors come with plastic aluminum or nickel-plated brass stem caps.
These caps should not be changed. Chrome plated steel caps may cause corrosion of aluminum
valve stems due to incompatibility of the metals.
On current style sensors the entire rubber stem is replaceable. The service interval on the revised
TPM sensor with replaceable stem is the same as for any other traditional valve stem. Replace the
stem at the time of tire replacement sensor transfer or whenever air seepage is suspected at the
valve stem. When replacing the valve stem tighten the screw to 1.3 N.m (11.5 lb in).
For either style of TPM sensor see the service parts guide for the correct GM part numbers to order
and use.
Disclaimer
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Center Link > Component Information > Service and
Repair
Center Link: Service and Repair
Relay Rod Replacement
Tools Required ^
J24319-B Universal Steering Linkage Puller
^ J29193 Steering Linkage Installer (12 mm)
^ J29194 Steering Linkage Installer (14 mm)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the engine protection shield, if equipped.
3. Remove the steering damper from the relay rod, if equipped.
Important: Use the proper tool in order to separate all the tie rod and the ball joints.
4. Remove the tie rod ends (6). 5. Remove the idler arm ball stud nut (10). Do not reuse the nut. 6.
Remove the pitman arm nut (8). Do not reuse the nut.
7. Remove the relay rod from the idler arm ball stud using the J24319-B. 8. Remove the relay rod
from the pitman arm ball stud using the J24319-B. 9. Remove the relay rod from the vehicle.
10. Inspect the threads on the tie rod ends for damage. 11. Inspect the ball stud threads for
damage. 12. Inspect the ball stud seals for excessive damage. 13. Clean the threads on the ball
studs.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Center Link > Component Information > Service and
Repair > Page 10083
1. Install the relay rod (9) to the vehicle. 2. Install the relay rod (9) to the pitman arm ball stud (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the relay rod (9) to the idler arm ball stud (1). Ensure the seal is on the stud.
4. Install the J29193 or the J29194. 5. Tighten the steering linkage installer in order to seat the
tapers.
Tighten the steering linkage installer to 54 Nm (40 ft. lbs.).
6. Remove the J29193 or the J29194. 7. Install the new pitman arm prevailing torque nut. 8. Install
the new idler arm prevailing torque nut.
Tighten the nuts to 62 Nm (46 ft. lbs.).
9. Install the tie rod ends.
10. Install the steering dampner to the relay rod, if equipped. 11. Install the engine protection
shield, if equipped. 12. Lower the vehicle. 13. Check the wheel alignment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Front Steering Knuckle > Component Information >
Service and Repair
Front Steering Knuckle: Service and Repair
Steering Knuckle Replacement
Tools Required ^
J43631 Ball Joint Separating Tool
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel.
3. Disconnect the Real Time Damping (RTD) link rod from the sensor, if equipped. 4. Unload the
torsion bars. 5. Remove the wheel hub and bearing assembly. 6. Disconnect the outer tie rod to the
steering knuckle. 7. Remove the brake hose bracket retaining bolt from the steering knuckle.
8. Remove the upper control arm retaining nut and separate the upper ball joint from the steering
knuckle (2) using the J43631 (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Front Steering Knuckle > Component Information >
Service and Repair > Page 10087
9. Remove the lower control arm retaining nut. Separate the lower ball joint from the steering
knuckle (2) using the J43631(1).
10. Remove the steering knuckle.
Installation Procedure
1. Clean all grease and contaminants from the tapered section and the threads of the upper ball
joint, the lower ball joint, and the tie rod end. 2. Clean and inspect the taper holes and the mounting
surfaces of the steering knuckle. If any of the tapered holes are elongated, out of round, or
damaged, replace the steering knuckle.
3. Install the steering knuckle.
Notice: Refer to Fastener Notice in Service Precautions.
4. Connect the lower ball joint to the steering knuckle and install the retaining nut.
Tighten the lower control arm retaining nut to 100 Nm (74 ft. lbs.).
5. Connect the upper ball joint to the steering knuckle and install the retaining nut.
Tighten the upper control arm retaining nut to 50 Nm (37 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Front Steering Knuckle > Component Information >
Service and Repair > Page 10088
6. Install the brake hose and the bracket retaining bolt to the steering knuckle
Tighten the bolt to 9 Nm (80 inch lbs.).
7. Connect the outer tie rod to the steering knuckle. 8. Install the wheel hub and bearing assembly.
9. Connect the RTD link rod to the sensor, if equipped.
10. Install the tire and wheel. 11. Load the torsion bars. 12. Align the vehicle. 13. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
Idler Arm: Specifications
Idler Arm to Frame Nut ........................................................................................................................
.................................................... 99 Nm (73 ft. lbs.) Idler Arm to Relay Rod Nut ...............................
...................................................................................................................................... 62 Nm (46 ft.
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10092
Idler Arm: Testing and Inspection
Idler Arm Inspection
Tools Required
^ J 35999 Spring Scale
^ J 42640 Steering Column Anti-Rotation Pin
^ J 45101 Hub and Wheel Runout Gauge
1. Raise the vehicle on a hoist. Support the vehicle with jackstands.
Notice: With wheels of the vehicle facing straight ahead, secure the steering wheel utilizing steering
column anti-rotation pin, steering column lock, or a strap to prevent rotation. Locking of the steering
column will prevent damage and a possible malfunction of the SIR system. The steering wheel
must be secured in position before disconnecting the following components:
^ The steering column
^ The intermediate shaft(s)
^ The steering gear
After disconnecting these components, do not rotate the steering wheel or move the front tires and
wheels. Failure to follow this procedure may cause the SIR coil assembly to become un-centered
and cause possible damage to the SIR coil. If you think the SIR coil has became un-centered, refer
to your specific SIR coil’s centering procedure to re-center SIR Coil.
2. Position the wheels in a straight-ahead position and install the J 42640. 3. Install the dial
indicator J 45101 between the idler arm and vehicle frame.
Ensure the gauge is at zero before taking a measurement.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10093
4. Place a J 35999 near the relay rod end of the idler arm.
5. Exert a 110 Nm (25 lb) force upward, and then downward while measuring the total distance the
arm moves.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10094
6. If movement exceeds 2 mm (0.078 in) replace the idler arm.
7. Install the dial indicator at the idler arm. 8. Push the tire inward slowly with one hand to remove
any lash.
Zero out the dial indicator and pull outward in order to take a reading.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10095
9. Allow only 1 mm (0.039 in) of movement at the idler arm ball stud.
If more than 1 mm exists, replace the idler arm.
10. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10096
Idler Arm: Service and Repair
Idler Arm Replacement
Tools Required
^ J24319-B Universal Steering Linkage Puller
^ J29193 Steering Linkage Installer (12 mm)
^ J29194 Steering Linkage installer (14 mm)
Removal Procedure
Notice: Do not attempt to free the ball stud by using a pickle fork or wedge type tool, because seal
or bushing damage could result. Use the proper tool to separate all ball joints.
1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the engine protection shield, if equipped. 3. Remove the idler arm ball stud nut (10).
Do not reuse the idler arm ball stud nut.
4. Remove the idler arm from the relay rod using the J24319-B.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10097
5. Remove the idler arm frame bolts (3) and the nuts (1). 6. Remove the idler arm (2) from the
vehicle.
Installation Procedure
1. Position the idler arm (2) on the frame.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the frame bolts (3) and the nuts (1) to the idler arm.
Tighten Tighten the frame bolts to 99 Nm (73 ft. lbs.).
3. Install the relay rod (9) to the idler arm ball stud (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Idler Arm > Component Information > Specifications
> Page 10098
Ensure the seal is on the stud.
4. Use the J29193 in order to seat the tapers.
Tighten Tighten the J29193 or the J29194 to 54 Nm (40 ft. lbs.) in order to seat the tapers.
5. Install the new idler arm ball stud prevailing torque nut to the idler arm ball stud.
Tighten Tighten the nut to 62 Nm (46 ft. lbs.).
6. Install the engine protection shield, if equipped. 7. Lower the vehicle. 8. Check the wheel
alignment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Pitman Arm > Component Information > Technical
Service Bulletins > Steering/Suspension - Pitman Arm Shaft Seal Service Kit
Pitman Arm: Technical Service Bulletins Steering/Suspension - Pitman Arm Shaft Seal Service Kit
INFORMATION
Bulletin No.: 10-02-33-001A
Date: October 13, 2010
Subject: Information on Pitman Arm Shaft Seal Service Kit
Models:
2004-2005 Buick Rainier 2000-2006 Cadillac Escalade, Escalade ESV, Escalade EXT 2000-2005
Chevrolet Blazer, S-10 2000-2011 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe
2000-2005 GMC Jimmy, Sonoma 2000-2011 GMC Savana, Sierra, Yukon, Yukon Denali, Yukon
XL, Yukon Denali XL 2000-2004 Oldsmobile Bravada 2003-2009 HUMMER H2 with Recirculating
Ball Steering Gears
Supercede: This bulletin is being revised to update the model years and models involved. Please
discard Corporate Bulletin Number 10-02-33-001 (Section 02 - Steering).
Note
Do not replace the entire steering gear for a pitman seal leak.
Technicians have been replacing entire steering gears due to not being able to service just the
leaking pitman shaft seal. The seal is serviced as a kit and is not called out separately in the
catalog illustration.
The seal package is cataloged in Group 06.855 as Seal Kit - GM Part Number 26002516 - Steering
Gear Pitman Shaft, which includes the seal, washer, retaining ring and dust seal or G/M P/N
19256667, which includes the seal and retainer. Refer to Steering Gear Pitman Shaft Seal in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Pitman Arm > Component Information > Technical
Service Bulletins > Page 10103
Pitman Arm: Specifications
Pitman Arm to Relay Rod Nut .............................................................................................................
...................................................... 62 Nm 46 ft. lbs. Pitman Arm to Steering Gear Nut
...........................................................................................................................................................
250 Nm 184 ft. lbs.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Pitman Arm > Component Information > Technical
Service Bulletins > Page 10104
Pitman Arm: Service and Repair
Pitman Arm Replacement
Tools Required ^
J6632-01 Pitman Arm Puller
^ J29193 Steering Linkage Installer (12 mm)
^ J29194 Steering Linkage Installer (14 mm)
^ J29107-A Universal Pitman Arm Puller
^ J24319-B Universal Steering Linkage Puller
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the engine protection shield, if equipped.
3. Remove the relay rod nut (8) from the pitman arm ball stud (2). Do not reuse the nut.
Notice: Do not hammer on the pitman arm, pitman arm shaft or puller. Damage to the pitman arm
or steering gear may result.
4. Use the J24319-B in order to remove the relay rod from the pitman arm ball stud. 5. Remove the
power steering gear.
Mark the pitman arm and the pitman shaft in order to ensure the proper alignment at assembly.
6. Remove the pitman arm nut.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Pitman Arm > Component Information > Technical
Service Bulletins > Page 10105
7. Use the J29107-A or J6632-01 in order to remove the pitman arm from the steering gear pitman
shaft. 8. Inspect the ball stud threads for damage. 9. Inspect the ball stud seals for excessive wear.
10. Clean the threads on the ball stud.
Installation Procedure
1. Install the pitman arm on the pitman shaft. 2. Align the marks made at the removal on the pitman
arm and the pitman arm shaft.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install a new pitman arm nut.
Tighten the pitman arm nut to 250 Nm (184 ft. lbs.).
4. Install the power steering gear. 5. Install the relay rod (9) to the pitman arm ball stud. 6. Ensure
the seal is on the stud.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Pitman Arm > Component Information > Technical
Service Bulletins > Page 10106
7. Install the J29193 or the J29194.
Tighten the J29193 or the J29194 to 54 Nm (40 ft. lbs.) in order to seat the tapers.
8. Remove the J29193 or the J29194. 9. Install the new relay rod prevailing torque nut.
Tighten the new prevailing torque nut to 62 Nm (46 ft. lbs.).
10. Install the engine protection shield, if equipped. 11. Lower the vehicle. 12. Check the wheel
alignment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Bleeding > System
Information > Service and Repair
Power Steering Bleeding: Service and Repair
Power Steering System Bleeding
Important:
- Use clean, new power steering fluid type only. See: Maintenance
- Hoses touching the frame, body or engine may cause system noise. Verify that the hoses do not
touch any other part of the vehicle.
- Loose connections may not leak, but could allow air into the steering system. Verify that all hose
connections are tight.
- Power steering fluid level must be maintained throughout bleed procedure.
1. Fill pump reservoir with fluid to minimum system level, FULL COLD level, or middle of hash mark
on cap stick fluid level indicator.
Important: With hydro-boost only, the oil level will appear falsely high if the hydro-boost
accumulator is not fully charged. Do not apply the brake pedal with the engine OFF. This will
discharge the hydro-boost accumulator.
2. If equipped with hydro-boost, fully charge the hydro-boost accumulator using the following
procedure:
2.1 Start the engine. 2.2 Firmly apply the brake pedal 10-15 times. 2.3 Turn the engine OFF.
3. Raise the vehicle until the front wheels are off the ground. 4. Key on engine OFF, turn the
steering wheel from stop to stop 12 times.
- Vehicle equipped with hydro-boost systems or longer length power steering hoses may require
turns up to 15 to 20 stop to stops.
5. Verify power steering fluid level per operation specification. See: Power Steering Fluid 6. Start
the engine. Rotate steering wheel from left to right. Check for sign of cavitation or fluid aeration
(pump noise/whining). 7. Verify the fluid level. Repeat the bleed procedure, if necessary.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid >
Component Information > Specifications
Power Steering Fluid: Specifications
Power Steering System GM Power Steering Fluid (GM Part No. 1052884 - 1 pint, 1050017 - 1
quart, or equivalent).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Cooler >
Component Information > Specifications
Power Steering Fluid Cooler: Specifications
Power Steering Cooler Mounting Bolts
..................................................................................................................................................... 5
Nm 44 inch lbs.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Cooler >
Component Information > Service and Repair > Without Hydroboost
Power Steering Fluid Cooler: Service and Repair Without Hydroboost
Power Steering Cooler Pipe/Hose Replacement (Without Hydroboost)
Removal Procedure
1. Remove the front grille.
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
2. Remove the clamp retaining the power steering outlet hose (3) from the power steering gear (4).
3. Remove the clamp retaining the power steering inlet hose from the power steering pump (5). 4.
Remove the bolts (2) retaining the power steering cooler from the radiator support. 5. Remove the
power steering cooler from the vehicle.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
1. Install the power steering cooler (1) to the vehicle.
Tighten the power steering cooler retaining bolts to 5 Nm (44 inch lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Cooler >
Component Information > Service and Repair > Without Hydroboost > Page 10119
2. Connect the power steering outlet hose (3) to the power steering gear (4). Install the retaining
clamp. 3. Connect the power steering inlet hose to the power steering pump. Install the retaining
clamp. 4. Bleed the power steering system. 5. Inspect all the hose connections for leaks. 6. Install
the front grille.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Cooler >
Component Information > Service and Repair > Without Hydroboost > Page 10120
Power Steering Fluid Cooler: Service and Repair With Hydroboost
Power Steering Cooler Pipe/Hose Replacement (With Hydroboost)
Removal Procedure
1. Remove the front grille.
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
2. Place a drain pan under the vehicle. 3. Siphon the fluid from the reservoir to prevent excess
spillage.
4. Remove the clamp retaining the power steering cooler inlet hose (3) to the power steering gear
(2). 5. Remove the clamp retaining power steering cooler outlet hose (5) to the power steering
pump (1).
6. Remove the bolts (2) retaining the power steering cooler from the radiator support. 7. Remove
the power steering cooler from the vehicle.
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Cooler >
Component Information > Service and Repair > Without Hydroboost > Page 10121
1. Install the power steering cooler (1) to the radiator support.
Tighten the bolts retaining the power steering cooler to 5 Nm (44 inch lbs.).
2. Install the power steering cooler outlet hose (3) to the power steering pump (2).
Install the retaining clamp.
3. Install the power steering inlet hose (5) to the power steering gear (1).
Install the retaining clamp.
4. Fill and bleed the power steering system. 5. Inspect all the hose connections for leaks. 6. Install
the front grille.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Fluid Reservoir >
Component Information > Service and Repair
Power Steering Fluid Reservoir: Service and Repair
"For information regarding this component please refer to power steering pump service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Specifications
Power Steering Line/Hose: Specifications
Pressure Hose Connection (At Gear)
........................................................................................................................................................ 33
Nm (24 ft. lbs.) Pressure Hose Connection (At Pump)
...................................................................................................................................................... 28
Nm (20 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Service and Repair > Power Brake Booster Inlet Hose Replacement
Power Steering Line/Hose: Service and Repair Power Brake Booster Inlet Hose Replacement
Power Brake Booster Inlet Hose Replacement
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the brake booster inlet hose (1) from the brake booster (2). 3. Remove the brake
booster inlet hose from the power steering pump. 4. Remove the brake booster inlet hose from the
vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the brake booster inlet hose (1) to the brake booster (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the brake booster inlet hose to the power steering pump.
Tighten the brake booster inlet hose fittings to 27 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Service and Repair > Power Brake Booster Inlet Hose Replacement > Page 10130
Power Steering Line/Hose: Service and Repair Power Brake Booster Outlet Hose Replacement
Power Brake Booster Outlet Hose Replacement
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the brake booster outlet hose (1) from the brake booster (2). 3. Remove the clamp
retaining the brake booster outlet hose to the power steering pump. 4. Remove the brake booster
outlet hose from the vehicle.
Installation Procedure
Notice: The inlet and outlet hoses must not be twisted during installation. Do not bend or distort the
inlet or outlet hoses to make installation easier. Failure to follow these procedures could result in
component damage.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the brake booster outlet hose (1) to the brake booster (2).
Position the clamp at the end of the hose.
3. Install the brake booster outlet hose to the power steering pump (4).
Position the clamp at the end of the hose.
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Service and Repair > Power Brake Booster Inlet Hose Replacement > Page 10131
Power Steering Line/Hose: Service and Repair Power Steering Gear Inlet Hose Replacement
With Hydroboost
Power Steering Gear Inlet Hose Replacement (With Hydroboost)
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the power steering gear inlet hose (1) from the brake booster. 3. Remove the power
steering gear inlet hose from the power steering gear. 4. Remove the power steering gear inlet
hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear inlet hose (1) to the brake booster (2).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear inlet hose to the power steering gear.
Tighten the power steering gear inlet hose fittings to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Service and Repair > Power Brake Booster Inlet Hose Replacement > Page 10132
Without Hydroboost
Power Steering Gear Inlet Hose Replacement (Without Hydroboost)
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Remove the engine protection shield.
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
3. Install a drain pan under the vehicle.
4. Remove the power steering gear inlet hose (3) from the power steering pump (1). 5. Remove the
power steering gear inlet hose from the power steering gear. 6. Remove the power steering gear
inlet hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear inlet hose (3) to the power steering pump (1).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear inlet hose to the power steering gear.
Tighten the power steering gear inlet hose fittings to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Install the engine protection shield. 6. Lower
the vehicle. 7. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Line/Hose >
Component Information > Service and Repair > Power Brake Booster Inlet Hose Replacement > Page 10133
Power Steering Line/Hose: Service and Repair Power Steering Gear Outlet Hose Replacement
Power Steering Gear Outlet Hose Replacement (Recirculating Ball)
Removal Procedure
Notice: Refer to Power Steering Hose Disconnected Notice in Service Precautions.
1. Install a drain pan under the vehicle.
2. Remove the power steering gear outlet hose (3) from the steering gear (2). 3. Remove the clamp
retaining the power steering gear outlet hose (3) to the power steering pump (1)
Remove the power steering gear outlet hose from the power steering pump.
4. Remove the power steering gear outlet hose from the vehicle.
Installation Procedure
Notice: Refer to Installing Hoses Without Twists or Bends Notice in Service Precautions.
1. Route the hose in the same position the hose occupied prior to removal.
2. Install the power steering gear outlet hose (3) to the power steering pump (1). Position the clamp
at the end of the hose.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the power steering gear outlet hose to the power steering gear.
Tighten the outlet hose fitting to 28 Nm (20 ft. lbs.).
4. Remove the drain pan from under the vehicle. 5. Bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Motor >
Component Information > Technical Service Bulletins > Steering - Power Steering Pump Replacement Tips
Power Steering Motor: Technical Service Bulletins Steering - Power Steering Pump Replacement
Tips
INFORMATION
Bulletin No.: 06-02-32-013B
Date: August 07, 2009
Subject: Diagnostic Tips/Recommendations When Power Steering Pump Replacement is
Necessary
Models:
1997-2010 GM Passenger Cars and Light Duty Trucks (including Saturn) 2010 and Prior HUMMER
H2, H3 2005-2009 Saab 9-7X
Supercede: This bulletin is being revised to add model years and update the information. Please
discard Corporate Bulletin Number 06-02-32-013A (Section 02 - Steering).
A recently completed analysis of returned power steering (PS) pumps that had been replaced for
noise, no power assist, no or low pressure and leaking conditions has indicated a high number of
"No Trouble Found" results.
Corporate Bulletin Number 01-02-32-004 indicates that when attempting to repair a power steering
concern, the steering system analyzer should be utilized to assist the technician in a successful
diagnosis. Note- Saturn ASTRA does not utilize the Power Steering System Analyzer.
In addition, extensive warranty analysis has shown that the following situations are all significant
root causes of PS pump failures:
- Improper pulley installation
- Re-using the O-rings
- Using fluid other than the OE-specified steering fluid
- Failure to flush the PS system
In order to help improve customer satisfaction and reduce comebacks, GM recommends the
following tips for replacing a PS pump:
1. Low or no pressure from the PS pump may be the results of dirty or contaminated fluid, which
could cause the pressure relief valve to stop
functioning. Using the proper tools, flush and bleed the PS system. Any residual contaminants will
result in pump failure.
2. When removing the pulley, use the proper special tools. Because the pulley alignment is critical,
distorting the pulley may damage bearings on the
new PS pump.
Note Some new PS pumps may not include a new O-ring. Please refer to the appropriate Parts
Catalog. Saturn retailers should refer to the appropriate model year Parts & Illustration Catalog for
the vehicle.
3. Be sure to use only the new O-rings included with the PS pump. The new reservoir O-ring must
be lubricated with OE-specific PS fluid prior to
installation. Also make sure that the control valve O-ring is in its exact groove position and is NOT
covering the pressure bypass hole.
4. Bleed the PS system according to the procedures/recommendations in SI.
Following these procedures and using the correct tools and fluids should help ensure that the new
PS pump operates properly. Skipping steps may cost you time and trouble later.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pressure Control
Valve > Component Information > Specifications
Power Steering Pressure Control Valve: Specifications
Flow Control Valve Actuator ................................................................................................................
................................................... 62 Nm (46 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pressure Control
Valve > Component Information > Specifications > Page 10141
Electronic Variable Orifice (EVO) Solenoid
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Technical Service Bulletins > Customer Interest for Power Steering Pump: > 01-02-32-007 > Sep
> 01 > Accessory Drive Belt - Whining Type Noise
Power Steering Pump: Customer Interest Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Power Steering Pump: >
01-02-32-007 > Sep > 01 > Accessory Drive Belt - Whining Type Noise
Power Steering Pump: All Technical Service Bulletins Accessory Drive Belt - Whining Type Noise
File In Section: 02 - Steering
Bulletin No.: 01-02-32-007
Date: September, 2001
TECHNICAL
Subject:
Accessory Drive Belt Whine (Reposition Power Steering Pump Pulley)
Models:
2001-02 Chevrolet and GMC C/K 1500 Series Utility Models (Tahoe, Suburban, Yukon, Yukon XL,
Denali, Denali XL) Built at Janesville Assembly Plant (Plant Code J) from December, 2000 through
July, 2001
Condition
Some customers may comment on a whining-type noise that is audible in the vehicle's passenger
compartment. This noise can typically be heard when the vehicle is idling and may vary in pitch as
engine RPM is increased.
Cause
The power steering (PS) pump pulley may be positioned too far inboard on the PS pump.
Correction
Inspect the PS pump pulley for proper positioning on the PS pump shaft. If it is determined that the
pulley is not even/flush with the end of the shaft (+/- 0.25 mm (0.010 in) following the applicable
Service Manual procedure and using J 25034-C, reposition the PS pump pulley.
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Specifications > Mechanical Specifications
Power Steering Pump: Mechanical Specifications
Power Steering Pump Front Mounting Bolts
............................................................................................................................................ 50 Nm (37
ft. lbs.) Power Steering Pump Rear Mounting Bolt
............................................................................................................................................... 50 Nm
(37 ft. lbs.) Flow Control Valve Actuator ..............................................................................................
..................................................................... 62 Nm (46 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Specifications > Mechanical Specifications > Page 10157
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Specifications > Page 10158
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Specifications > Page 10159
Power Steering Pump: Testing and Inspection
Please see STEERING/TESTING and INSPECTION for information on this component.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement
Power Steering Pump: Service and Repair Power Steering Pulley Replacement
Power Steering Pulley Replacement
Tools Required ^
J25034-C Power Steering Pump Pulley Remover
^ J25033-C Power Steering Pump Pulley Installer
Removal Procedure
1. Remove the upper fan shroud. 2. Remove the drive belt.
3. Remove the power steering pump pulley using the J25034-C.
Installation Procedure
1. Place the power steering pump pulley on the end of the power steering pump shaft. 2. Install the
power steering pump pulley using J25033-C.
3. Ensure that the power steering pump pulley is flush against the power steering pump shaft, with
an allowable variance of 0.25 mm (0.010 inch).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10162
4. Install the drive belt. 5. Install the upper fan shroud.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10163
Power Steering Pump: Service and Repair Power Steering Pump Flow Control Valve Actuator
Replacement - On Vehicle
Power Steering Pump Flow Control Valve Actuator Replacement - On Vehicle
Disassembly Procedure
1. Remove the electrical connector from the variable assist steering actuator (1). 2. Remove pump
assembly from the vehicle, if the variable assist steering actuator (1) is not accessible. 3. Remove
the retaining ring (2) from the variable assist steering actuator (1).
Important: Note the orientation of the variable assist steering actuator discharge fitting.
4. Remove the variable assist steering actuator (1). 5. Remove the O-ring seal from the variable
assist steering actuator.
Assembly Procedure
Important: Note the orientation of the variable assist steering actuator discharge fitting.
1. Lubricate and install the new O-ring seal with power steering fluid.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the variable assist steering actuator (1) to the pump assembly.
Tighten the actuator to 62 Nm (46 ft. lbs.).
3. Install the negative battery cable.
Important: If a new variable assist steering actuator (1) is being installed, position the electrical
connector before installing the retaining ring (2).
4. Install the electrical connector to the variable assist steering actuator (1). 5. Install the retaining
ring (2) to the variable assist steering actuator (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10164
Power Steering Pump: Service and Repair Power Steering Pump Flow Control Valve Replacement
- Off Vehicle (Regular)
Power Steering Pump Flow Control Valve Replacement - Off Vehicle (Regular)
Disassembly Procedure
1. Drain the oil from the reservoir (1). 2. Remove the control valve assembly (3) from the pump
housing (1). Make sure the flow control spring (4) does not fall out of the pump housing
(1).
3. Remove the rectangular section seal (2) from the control valve assembly (3).
Assembly Procedure
1. Install the flow control spring (4) if removed from the pump housing (1). 2. Lubricate the new
rectangular section seal (2) with power steering fluid. 3. Install the rectangular section seal (2) onto
the control valve assembly (3). 4. Install the control valve assembly (3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10165
Power Steering Pump: Service and Repair Power Steering Pump Replacement
Power Steering Pump Replacement
Removal Procedure
1. Remove the power steering pulley. 2. Place a drain pan under the pump. 3. Remove the hose
guide bracket from the front of the pump. 4. For vehicles with variable effort steering, disconnect
the electrical connector. 5. Remove the hoses from the pump. 6. Remove the lower intermediate
shaft from the steering gear.
7. Remove the bolt retaining the rear bracket to the engine. 8. Remove the bolts from the front of
the pump. 9. Remove the pump from the vehicle.
10. Remove the bracket (3) from the rear of the pump (1).
Installation Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10166
1. Install the bracket (3) to the rear of the pump (1).
Tighten the rear bracket retaining nuts to 50 Nm (37 ft. lbs.).
2. Install the pump. 3. Install the hose guide bracket bolt to the pump.
4. Install the bolt retaining the rear bracket to the engine. 5. Install the bolts to the front of the
pump.
Tighten the bolts to 50 Nm (37 ft. lbs.).
6. For vehicles with variable effort steering connect the electrical connector. 7. Install the hoses to
the pump.
Tighten the nut to 28 Nm (20 ft. lbs.).
8. Install the intermediate shaft. 9. Install the power steering pulley.
10. Fill and bleed the power steering system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10167
Power Steering Pump: Service and Repair Power Steering Reservoir Replacement - Off Vehicle
Power Steering Reservoir Replacement - Off Vehicle
Disassembly Procedure
1. Drain the power steering fluid from the power steering pump.
2. Remove the pump mounting studs (2). 3. Remove the connector and fitting assembly (5). To
remove the variable assist steering actuator (3) and retaining ring (4); refer to Power Steering
Pump Flow Control Valve Actuator Replacement - On Vehicle.
4. Remove the O-ring seal (6) from the connector and fitting assembly (4). 5. If replacement is
required, remove the control valve assembly and the flow control spring from the pump housing
assembly.
6. Remove the reservoir assembly (1) from the pump housing assembly (2).
7. Remove the O-ring seals (1) (4). 8. Remove the magnet (3). 9. Clean the magnet (3).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10168
10. Inspect the Welch plug in the power steering pump housing (2). Do not remove. If the Welch
plug is deformed or dislodged, replace the power
steering pump housing (2).
Assembly Procedure
Important: Use new O-ring seals when assembling the power steering pump assembly.
1. Lubricate the O-ring seals (1) (4) with power steering fluid. 2. To install the control valve
assembly and flow control spring to the pump housing assembly (2); refer to Power Steering Pump
Flow Control Valve
Replacement - Off Vehicle (Regular).
3. Install the O-ring seals (1) (4) to the pump housing assembly (2). 4. Install the magnet (3) to the
pump housing assembly (2).
5. Connect the reservoir assembly (1) to the pump housing assembly (2). 6. Install the O-ring seal.
7. Install the connector and fitting assembly (5). To install the variable assist steering actuator (3)
and retaining ring (4); refer to Power Steering
Pump Flow Control Valve Actuator Replacement - On Vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Power Steering > Power Steering Pump >
Component Information > Service and Repair > Power Steering Pulley Replacement > Page 10169
Notice: Refer to Fastener Notice in Service Precautions.
8. Install the pump mounting studs (2) to the pump housing (1).
Tighten the pump mounting studs (2) to 58 Nm (43 ft. lbs.). Tighten the connector and fitting
assembly (5) to 75 Nm (55 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Angle
Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Angle
Sensor > Component Information > Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Angle
Sensor > Component Information > Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD > Page 10176
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Angle
Sensor > Component Information > Diagrams > Page 10177
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Angle
Sensor > Component Information > Diagrams > Page 10178
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures
Steering Column Position Sensor: Technical Service Bulletins Steering - Revised Service
Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10183
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10184
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10185
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10186
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10187
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10188
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10189
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page
10190
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10191
Steering Column Position Sensor: Service and Repair
This article has been updated with TSB# 03-02-36-002
REVISED STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT PROCEDURE AND STEERING WHEEL POSITION SENSOR CENTERING
PROCEDURE
STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. 2. Remove the steering column from the vehicle.
3. Remove the following from the steering shaft:
A. steering shaft seal (7) B. sensor retainer (6) C. steering wheel position sensor (5), refer to
Steering Wheel Position Sensor Centering. D. two lower spring retainers (4) E. lower bearing
spring (3) F. lower bearing seat (2) G. adapter and bearing assembly (1)
INSTALLATION PROCEDURE
1. Install the following onto the steering shaft:
A. adapter and bearing assembly (1) B. lower bearing seat (2) C. lower bearing spring (3) D. 2
lower spring retainers (4) E. steering wheel position sensor (5) refer to Steering Wheel Position
Sensor Centering. F. sensor retainer (6) G. steering shaft seal (7) H. Enable the SIR system.
2. Install the steering column to the vehicle. 3. Enable the SIR system.
STEERING WHEEL POSITION SENSOR CENTERING
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10192
IMPORTANT: Identify the type of steering wheel position sensor from the illustrations below
BEFORE removing the sensor from the steering column. Once you have identified the steering
wheel position sensor, follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
IMPORTANT: If reusing the existing sensor, you do not have to align the sensor before removal.
Centering is not required when it is time to reinstall.
3. Remove the connector from the sensor. 4. Remove the sensor (1) from the adapter and bearing
assembly. 5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
IMPORTANT: If reusing the existing sensor, you must make an alignment mark on the rotor flange
cuff (3) before removing the sensor. Failure to do so will cause misalignment when installing the
sensor. A new sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3). 8. Remove the connector from the
sensor. 9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10193
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor. 13. Remove the sensor from the adapter and bearing
assembly. 14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor. 17. Remove the sensor clip from the sensor. 18.
Remove the sensor from the adapter and bearing assembly. 19. To install the sensor, proceed to
step 13 in the installation section.
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor. 22. Remove the sensor from the adapter and bearing
assembly. 23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10194
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor. 26. Remove the sensor from the adapter and bearing
assembly. 27. To install the sensor, proceed to step 21 in the installation section.
INSTALLATION PROCEDURE
IMPORTANT: If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of
the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 4. Install the connector to the sensor. 5. From the technicians point
of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 8. Install the connector to the sensor.
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10195
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 20. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Sensors and Switches - Steering > Steering Column
Position Sensor > Component Information > Technical Service Bulletins > Page 10196
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 24. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Angle Sensor > Component Information >
Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Angle Sensor > Component Information >
Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Angle Sensor > Component Information >
Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD > Page 10202
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Angle Sensor > Component Information >
Diagrams > Page 10203
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Angle Sensor > Component Information >
Diagrams > Page 10204
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Air Bag(s) Arming and Disarming
> System Information > Service and Repair > Disabling
Air Bag(s) Arming and Disarming: Service and Repair Disabling
IMPORTANT: Refer to SIR Service Precautions before disabling the SIR system.
1. Turn the steering wheel until the vehicle's wheels are pointing straight ahead. 2. Turn OFF the
ignition. 3. Remove the key from the ignition.
IMPORTANT: With the AIR BAG Fuse removed and the ignition ON, the AIR BAG indicator
illuminates. This is normal operation and does not indicate an SIR system malfunction.
4. Remove the AIR BAG Fuse from the fuse block. 5. Remove the connector position assurance
(CPA) (1) from the steering wheel module yellow 2-way connector (2) located at the base of the
steering
column.
6. Disconnect the steering wheel module yellow 2-way connector (2) located at the base of the
steering column.
7. Access the IP module yellow 2-way connector (1) located behind the IP module (2) by removing
the upper IP trim panel. Refer to Trim Pad
Replacement - IP Upper in Instrument Panel, Gauges and Warning Indicators.
8. Remove the CPA from the IP module yellow 2-way connector (1) located behind the IP module
(2). 9. Disconnect the IP module yellow 2-way connector (1) located behind the IP module (2).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Air Bag(s) Arming and Disarming
> System Information > Service and Repair > Disabling > Page 10210
Air Bag(s) Arming and Disarming: Service and Repair Enabling
1. Remove the key from the ignition. 2. Connect the IP module yellow 2-way connector (1) located
behind the main IP support. 3. Install the CPA to the IP module yellow 2-way connector (1) located
behind the main IP support.
4. Connect the steering wheel module yellow 2-way connector (2) located at the base of the
steering column. 5. Install the CPA (1) to the steering wheel module yellow 2-way connector (2)
located at the base of the steering column. 6. Install the AIR BAG Fuse to the fuse block. 7. Staying
well away from all air bags, turn ON the ignition, with the engine OFF.
7.1. The AIR BAG indicator will flash 7 times.
7.2. The AIR BAG indicator will then turn OFF.
8. Perform the Diagnostic System Check - SIR if the AIR BAG indicator does not operate as
described.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering Underhood Clunk Heard/Felt in Steering Wheel
Steering Column Bearing: Customer Interest Steering - Underhood Clunk Heard/Felt in Steering
Wheel
TECHNICAL
Bulletin No.: 00-02-35-003N
Date: March 26 2008
Subject: Clunking Noise Under Hood and Can Be Felt in Steering Wheel and/or Steering Column
(Replace Upper Intermediate Steering Shaft [I-Shaft] Assembly)
Models: 2002-2006 Cadillac Escalade Models 1999-2007 Chevrolet Silverado Models (Classic)
2000-2006 Chevrolet Suburban, Tahoe Models 2002-2006 Chevrolet Avalanche 1999-2007 GMC
Sierra Models (Classic) 2000-2006 GMC Yukon, Yukon XL Models 2003-2006 HUMMER H2
Attention:
This Service Bulletin DOES NOT include Mid-Size Utilities such as Buick Rainier, Chevrolet
TrailBlazer Models, GMC Envoy Models or Oldsmobile Bravada. Refer to Service Bulletin
02-02-35-006A or newer for Mid-Size Utilities.
Supercede:
This bulletin is being revised to add diagnostic information (refer to Diagnostic Tips) to check the
lower steering column bearing as a potential source of the noise. Please discard Corporate Bulletin
Number 00-02-35-003M (Section 02-Steering).
Condition
Some customers may comment on a clunk-type noise coming from under the hood that also can be
felt in the steering wheel. These conditions may be more noticeable when turning at low speeds on
rough road surfaces.
Diagnostic Tips
Use the information below to help diagnose the source of the noise.
^ The lower steering column bearing may create the same noise as the intermediate shaft. Before
replacing the I-shaft, verify the noise isn't being caused by movement from the lower steering
column bearing. Check the bearing for movement by pushing up and down on the I-shaft where it
attaches to the steering column.
^ Frame Snap and/or Popping Type Noise - A frame snap or popping type noise can be duplicated
on rough or smooth road surfaces with steering wheel input to the left or the right. This type of
noise can be HEARD and is typically louder with the windows rolled down. For additional
information refer to Corporate Bulletin Number 03-08-61-002F or newer - Snap/Popping Type
Noise Coming from Front of Vehicle (Remove Front Crossmember Change Fastener Orientation).
^ Intermediate Shaft Clunk - Intermediate shaft clunk is heard and FELT in the steering wheel
and/or steering column area typically while driving on rough road surfaces with steering wheel
input.
Correction
Important:
^ I-shaft P/N 19153614 has been designed to replace previous designed dampened and
non-dampened I-shafts. The physical difference in the yoke size will accommodate all vehicles
listed in this bulletin.
^ Due to the design of the new I-shaft, it is not possible to lubricate/grease the I-shaft.
Replace the steering column upper intermediate shaft with an improved design shaft that will
eliminate the clunk noise using the procedure listed below.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering Underhood Clunk Heard/Felt in Steering Wheel > Page 10219
1. Set the front wheels in the straight ahead position.
Notice:
On the 2002 and later model year vehicles the steering column LOCK was removed from the
steering column. It is critical that the J 42640 - Steering column Anti-Rotation Pin is used when
servicing steering columns on 2002 and later model year vehicles. Failure to use the J 42640 may
result in damage to the SIR coil.
2. Set the steering wheel in the LOCK position on 2001 and prior model year vehicles.
3. For 2002 and later vehicles install the J 42640 in the steering column lower access hole.
4. From under the hood remove the lower bolt that connects the upper intermediate shaft to the
steering gear coupling shaft.
5. Slide the shaft towards the dash in order to disengage the shaft from the steering gear coupling
shaft.
6. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the carpet away from the accelerator pedal position (APP) sensor.
2. Remove the two nuts retaining the accelerator pedal to the bulkhead.
3. Reposition the accelerator pedal out of the way so the intermediate shaft can be removed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering Underhood Clunk Heard/Felt in Steering Wheel > Page 10220
7. From inside the vehicle remove the upper bolt from the upper intermediate steering shaft (1) to
the steering column connection.
8. Remove the upper intermediate steering shaft assembly.
1. From inside the vehicle slide the shaft down and off the steering column.
2. From inside the vehicle slide the upper intermediate shaft through the dash boot seal and
remove the shaft from the vehicle.
9. Replace the upper intermediate shaft.
10. Install the upper intermediate steering shaft through the dash boot seal and slide the lower end
into the steering gear coupling shaft.
11. Raise the upper end of the intermediate steering shaft and install into the steering column shaft.
12. Install the upper bolt and nut.
Tighten
Tighten the bolt to 47 N.m (35 lb ft).
13. Install the lower bolt and nut.
Tighten
Tighten the bolt to 50 N.m (37 lb ft).
14. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the accelerator pedals into position on the bulkhead.
2. Install the two retaining nuts.
Tighten
Tighten the nuts to 20 N.m (15 lb ft).
3. Reposition the carpet into place.
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering Underhood Clunk Heard/Felt in Steering Wheel > Page 10221
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering Wheel
Steering Column Bearing: All Technical Service Bulletins Steering - Underhood Clunk Heard/Felt in
Steering Wheel
TECHNICAL
Bulletin No.: 00-02-35-003N
Date: March 26 2008
Subject: Clunking Noise Under Hood and Can Be Felt in Steering Wheel and/or Steering Column
(Replace Upper Intermediate Steering Shaft [I-Shaft] Assembly)
Models: 2002-2006 Cadillac Escalade Models 1999-2007 Chevrolet Silverado Models (Classic)
2000-2006 Chevrolet Suburban, Tahoe Models 2002-2006 Chevrolet Avalanche 1999-2007 GMC
Sierra Models (Classic) 2000-2006 GMC Yukon, Yukon XL Models 2003-2006 HUMMER H2
Attention:
This Service Bulletin DOES NOT include Mid-Size Utilities such as Buick Rainier, Chevrolet
TrailBlazer Models, GMC Envoy Models or Oldsmobile Bravada. Refer to Service Bulletin
02-02-35-006A or newer for Mid-Size Utilities.
Supercede:
This bulletin is being revised to add diagnostic information (refer to Diagnostic Tips) to check the
lower steering column bearing as a potential source of the noise. Please discard Corporate Bulletin
Number 00-02-35-003M (Section 02-Steering).
Condition
Some customers may comment on a clunk-type noise coming from under the hood that also can be
felt in the steering wheel. These conditions may be more noticeable when turning at low speeds on
rough road surfaces.
Diagnostic Tips
Use the information below to help diagnose the source of the noise.
^ The lower steering column bearing may create the same noise as the intermediate shaft. Before
replacing the I-shaft, verify the noise isn't being caused by movement from the lower steering
column bearing. Check the bearing for movement by pushing up and down on the I-shaft where it
attaches to the steering column.
^ Frame Snap and/or Popping Type Noise - A frame snap or popping type noise can be duplicated
on rough or smooth road surfaces with steering wheel input to the left or the right. This type of
noise can be HEARD and is typically louder with the windows rolled down. For additional
information refer to Corporate Bulletin Number 03-08-61-002F or newer - Snap/Popping Type
Noise Coming from Front of Vehicle (Remove Front Crossmember Change Fastener Orientation).
^ Intermediate Shaft Clunk - Intermediate shaft clunk is heard and FELT in the steering wheel
and/or steering column area typically while driving on rough road surfaces with steering wheel
input.
Correction
Important:
^ I-shaft P/N 19153614 has been designed to replace previous designed dampened and
non-dampened I-shafts. The physical difference in the yoke size will accommodate all vehicles
listed in this bulletin.
^ Due to the design of the new I-shaft, it is not possible to lubricate/grease the I-shaft.
Replace the steering column upper intermediate shaft with an improved design shaft that will
eliminate the clunk noise using the procedure listed below.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering Wheel > Page 10227
1. Set the front wheels in the straight ahead position.
Notice:
On the 2002 and later model year vehicles the steering column LOCK was removed from the
steering column. It is critical that the J 42640 - Steering column Anti-Rotation Pin is used when
servicing steering columns on 2002 and later model year vehicles. Failure to use the J 42640 may
result in damage to the SIR coil.
2. Set the steering wheel in the LOCK position on 2001 and prior model year vehicles.
3. For 2002 and later vehicles install the J 42640 in the steering column lower access hole.
4. From under the hood remove the lower bolt that connects the upper intermediate shaft to the
steering gear coupling shaft.
5. Slide the shaft towards the dash in order to disengage the shaft from the steering gear coupling
shaft.
6. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the carpet away from the accelerator pedal position (APP) sensor.
2. Remove the two nuts retaining the accelerator pedal to the bulkhead.
3. Reposition the accelerator pedal out of the way so the intermediate shaft can be removed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering Wheel > Page 10228
7. From inside the vehicle remove the upper bolt from the upper intermediate steering shaft (1) to
the steering column connection.
8. Remove the upper intermediate steering shaft assembly.
1. From inside the vehicle slide the shaft down and off the steering column.
2. From inside the vehicle slide the upper intermediate shaft through the dash boot seal and
remove the shaft from the vehicle.
9. Replace the upper intermediate shaft.
10. Install the upper intermediate steering shaft through the dash boot seal and slide the lower end
into the steering gear coupling shaft.
11. Raise the upper end of the intermediate steering shaft and install into the steering column shaft.
12. Install the upper bolt and nut.
Tighten
Tighten the bolt to 47 N.m (35 lb ft).
13. Install the lower bolt and nut.
Tighten
Tighten the bolt to 50 N.m (37 lb ft).
14. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the accelerator pedals into position on the bulkhead.
2. Install the two retaining nuts.
Tighten
Tighten the nuts to 20 N.m (15 lb ft).
3. Reposition the carpet into place.
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering Wheel > Page 10229
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures
Steering Column Bearing: All Technical Service Bulletins Steering - Revised Service Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10234
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10235
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10236
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10237
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10238
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10239
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10240
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Technical Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10241
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures
Steering Column Bearing: All Technical Service Bulletins Steering - Revised Service Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10247
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10248
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10249
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10250
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10251
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10252
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10253
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Bearing >
Component Information > Technical Service Bulletins > All Other Service Bulletins for Steering Column Bearing: >
03-02-36-002 > Jul > 03 > Steering - Revised Service Procedures > Page 10254
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures
Steering Column Position Sensor: Technical Service Bulletins Steering - Revised Service
Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10259
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10260
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10261
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10262
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10263
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10264
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10265
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Steering - Revised Service Procedures > Page 10266
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10267
Steering Column Position Sensor: Service and Repair
This article has been updated with TSB# 03-02-36-002
REVISED STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT PROCEDURE AND STEERING WHEEL POSITION SENSOR CENTERING
PROCEDURE
STEERING WHEEL POSITION SENSOR OR STEERING SHAFT LOWER BEARING
REPLACEMENT
REMOVAL PROCEDURE
CAUTION: Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. 2. Remove the steering column from the vehicle.
3. Remove the following from the steering shaft:
A. steering shaft seal (7) B. sensor retainer (6) C. steering wheel position sensor (5), refer to
Steering Wheel Position Sensor Centering. D. two lower spring retainers (4) E. lower bearing
spring (3) F. lower bearing seat (2) G. adapter and bearing assembly (1)
INSTALLATION PROCEDURE
1. Install the following onto the steering shaft:
A. adapter and bearing assembly (1) B. lower bearing seat (2) C. lower bearing spring (3) D. 2
lower spring retainers (4) E. steering wheel position sensor (5) refer to Steering Wheel Position
Sensor Centering. F. sensor retainer (6) G. steering shaft seal (7) H. Enable the SIR system.
2. Install the steering column to the vehicle. 3. Enable the SIR system.
STEERING WHEEL POSITION SENSOR CENTERING
REMOVAL PROCEDURE
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10268
IMPORTANT: Identify the type of steering wheel position sensor from the illustrations below
BEFORE removing the sensor from the steering column. Once you have identified the steering
wheel position sensor, follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
IMPORTANT: If reusing the existing sensor, you do not have to align the sensor before removal.
Centering is not required when it is time to reinstall.
3. Remove the connector from the sensor. 4. Remove the sensor (1) from the adapter and bearing
assembly. 5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
IMPORTANT: If reusing the existing sensor, you must make an alignment mark on the rotor flange
cuff (3) before removing the sensor. Failure to do so will cause misalignment when installing the
sensor. A new sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3). 8. Remove the connector from the
sensor. 9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10269
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor. 13. Remove the sensor from the adapter and bearing
assembly. 14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor. 17. Remove the sensor clip from the sensor. 18.
Remove the sensor from the adapter and bearing assembly. 19. To install the sensor, proceed to
step 13 in the installation section.
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor. 22. Remove the sensor from the adapter and bearing
assembly. 23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10270
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor. 26. Remove the sensor from the adapter and bearing
assembly. 27. To install the sensor, proceed to step 21 in the installation section.
INSTALLATION PROCEDURE
IMPORTANT: If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of
the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 4. Install the connector to the sensor. 5. From the technicians point
of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 8. Install the connector to the sensor.
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10271
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the raised rotor flange
cuff before installation. The alignment mark must stay aligned until the sensor is seated into the
adapter and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D
flats.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT:If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 20. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Column > Steering Column Position Sensor
> Component Information > Technical Service Bulletins > Page 10272
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
IMPORTANT: If reusing the existing sensor, you must align the marks on the flush rotor flange cuff
before installation. The alignment mark must stay aligned until the sensor is seated into the adapter
and bearing assembly.
IMPORTANT: If installing a new sensor, it will come with a pin installed in the sensor. Do not
remove the pin until the sensor is seated. If the new sensor did not come with a pin installed, you
must reorder a new sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly. 24. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Damper > Component Information >
Specifications
Steering Damper: Specifications
Steering Dampner to Frame Bracket Nut
.................................................................................................................................................. 40 Nm
(30 ft. lbs.) Steering Dampner to Relay Rod Nut
........................................................................................................................................................ 62
Nm (46 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Damper > Component Information >
Specifications > Page 10276
Steering Damper: Service and Repair
Steering Damper Replacement
Tools Required ^
J24319-B Universal Steering Linkage Puller
^ J29193 Steering Linkage Installer-12 mm
Removal Procedure
1. Raise the vehicle. Support the vehicle with safety stands. Refer to Vehicle Lifting. 2. Remove the
engine protection shield, if equipped.
Important: Do not reuse the nut.
3. Remove the steering damper (2) ball stud nut (1).
4. Remove the steering damper ball stud from the relay rod using the J24319-B.
Important: Do not reuse the nut.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Damper > Component Information >
Specifications > Page 10277
5. Remove the steering damper mounting bolt (5) and the nut (6). 6. Remove the steering damper
(4) from the vehicle. 7. Inspect the following parts:
^ The steering damper for leaks and damage
^ The mounting bolts and the nuts for damage or corrosion
Installation Procedure
1. Install the steering damper (4). 2. Install the mounting bolt (5) and a new prevailing torque nut
(6). 3. Install the steering damper ball stud (2) to the relay rod (3).
Notice: Refer to Fastener Notice in Service Precautions.
4. Install the J29193. 5. Tighten the steering linkage installer in order to seat the ball stud in the
relay rod.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Damper > Component Information >
Specifications > Page 10278
Tighten the installer to 54 Nm (40 ft. lbs.).
6. Remove the J29193. 7. Install the prevailing torque nuts.
Tighten the mounting nut to 40 Nm (30 ft. lbs.). Tighten the ball stud nut to 62 Nm (46 ft. lbs.).
8. Install the engine protection shield, if equipped. 9. Lower the vehicle.
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Gear > Steering Gear Seal > Component
Information > Technical Service Bulletins > Steering/Suspension - Pitman Arm Shaft Seal Service Kit
Steering Gear Seal: Technical Service Bulletins Steering/Suspension - Pitman Arm Shaft Seal
Service Kit
INFORMATION
Bulletin No.: 10-02-33-001A
Date: October 13, 2010
Subject: Information on Pitman Arm Shaft Seal Service Kit
Models:
2004-2005 Buick Rainier 2000-2006 Cadillac Escalade, Escalade ESV, Escalade EXT 2000-2005
Chevrolet Blazer, S-10 2000-2011 Chevrolet Avalanche, Express, Silverado, Suburban, Tahoe
2000-2005 GMC Jimmy, Sonoma 2000-2011 GMC Savana, Sierra, Yukon, Yukon Denali, Yukon
XL, Yukon Denali XL 2000-2004 Oldsmobile Bravada 2003-2009 HUMMER H2 with Recirculating
Ball Steering Gears
Supercede: This bulletin is being revised to update the model years and models involved. Please
discard Corporate Bulletin Number 10-02-33-001 (Section 02 - Steering).
Note
Do not replace the entire steering gear for a pitman seal leak.
Technicians have been replacing entire steering gears due to not being able to service just the
leaking pitman shaft seal. The seal is serviced as a kit and is not called out separately in the
catalog illustration.
The seal package is cataloged in Group 06.855 as Seal Kit - GM Part Number 26002516 - Steering
Gear Pitman Shaft, which includes the seal, washer, retaining ring and dust seal or G/M P/N
19256667, which includes the seal and retainer. Refer to Steering Gear Pitman Shaft Seal in SI.
Parts Information
Warranty Information
For vehicles repaired under warranty, use the table.
Disclaimer
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Component Information > Locations
Locations View
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Steering Mounted Controls Transmitter: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Steering Mounted Controls Transmitter: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
opened, by removing the voltage from its terminals. Once the voltage is removed the circuit breaker
will re-close within a second or 2.
Fusible Links
Fusible link is wire designed to melt and break continuity when excessive current is applied. It is
often located between or near the battery and starter or electrical center. Use a continuity tester or
a DMM at each end of the wire containing the fusible link in order to determine if it is broken. If
broken, it must be replaced with fusible link of the same gage size.
Repairing a Fusible Link
IMPORTANT: Fusible links cut longer than 225 mm (approximately 9 in) will not provide sufficient
overload protection.
General Information
The Connector Repairs contains the following types of connector repair information. Using these
elements together will make connector repair faster and easier:
- Connector Position Assurance Locks
- Terminal Position Assurance Locks
- Push to Seat Connectors
- Pull to Seat Connectors
- Weather Pack Connectors
- Repairing Connector Terminals
Connector Position Assurance Locks
The connector position assurance (CPA) is a small plastic insert that fits through the locking tabs of
all the SIR system electrical connectors. The CPA ensures that the connector halves cannot vibrate
apart. You must have the CPA in place in order to ensure good contact between the SIR mating
terminals.
Pull to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair pull-to-seat connectors.
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1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves. 3. Using the proper pick or
removal tool insert into the front of the connector body. 4. Grasp the wire at the back of the
connector body and gently pull the terminal (1) from the connector body (3). 5. Inspect the terminal
for damage, if damaged refer to Terminal Repair. 6. Reform the locking tang (2) if the terminal is
being reused.
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
TERMINAL INSTALLATION
1. Inspect the terminal for damage. If damaged refer to Terminal Repair. 2. Reform the locking tang
(2) if the terminal is being reused. 3. Ensure that the cable seal is kept on the terminal side of the
splice. 4. Insert the wire into the back of the connector body. Push until the terminal locking tang
locks into the connector body. 5. Install the TPA, CPA and/or the secondary locks.
Push to Seat Connectors
TERMINAL REMOVAL
Follow the steps below in order to repair push to seat connectors.
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Component Information > Diagrams > Diagram Information and Instructions > Page 10302
1. Remove the terminal position assurance (TPA) device, the connector position assurance (CPA)
device, and/or the secondary lock. 2. Separate the connector halves (1).
3. Use the proper pick or removal tool (1) in order to release the terminal. 4. Gently pull the cable
and the terminal (2) out of the back of the connector.
5. Re-form the locking device if you are going to reuse the terminal (1). 6. To repair the terminal,
refer to Terminal Repair.
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Diagram Information and Instructions > Page 10303
TERMINAL REPAIR
1. Slip the cable seal away from the terminal. 2. Cut the wire as close to the terminal as possible. 3.
Slip a new cable seal onto the wire. 4. Strip 5 mm (3/16 in) of insulation from the wire. 5. Crimp a
new terminal to the wire. 6. Solder the crimp with rosin core solder. 7. Slide the cable seal toward
the terminal. 8. Crimp the cable seal and the insulation. 9. If the connector is outside of the
passenger compartment, apply grease to the connector.
REINSTALLING TERMINAL
1. In order to reuse a terminal or lead assembly. Refer to Wiring Repairs. 2. Ensure that the cable
seal is kept on the terminal side of the splice. 3. Insert the lead from the back until it catches. 4.
Install the TPA, CPA and/or the secondary locks.
Repairing Connector Terminals
TOOLS REQUIRED
J 38125-B Terminal Repair kit
Use the following repair procedures in order to repair the following.
- Push to Seat terminals
- Pull to Seat terminals
- Weather Pack(R) terminals
Some terminals do not require all of the steps shown. Skip the steps that do not apply for your
immediate terminal repair. The J 38125-B contains further information.
1. Cut off the terminal between the core and the insulation crimp. Minimize any wire loss. For
Weather Pack(R) terminals, remove the seal. 2. Apply the correct seal per gage size of the wire.
For Weather Pack(R) terminals, slide the seal back along the wire in order to enable insulation
removal.
3. Remove the insulation. 4. For Weather Pack(R) terminals only, align the seal with the end of the
cable insulation. 5. Position the strip in the terminal
For Weather Pack(R) terminals, position the strip and seal in the terminal.
6. Hand crimp the core wings. 7. Hand crimp the insulation wings.
For Weather Pack(R) terminals, hand crimp the insulation wings around the seal and the cable.
8. Solder all of the hand crimp terminals.
Terminal Position Assurance Locks
The terminal position assurance (TPA) insert resembles the plastic combs used in the control
module connectors. The TPA keeps the terminal securely seated in the connector body. Do not
remove the TPA from the connector body unless you remove a terminal for replacement.
Weather Pack Connectors
The following is the proper procedure for the repair of Weather Pack(R) Connectors.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 10304
1. Separate the connector halves (1). 2. Open the secondary lock. A secondary lock aids in
terminal retention and is usually molded to the connector (1). 3. Grasp the wire and push the
terminal to the forward most position. Hold the wire in this position.
4. Insert the Weather Pack(R) terminal removal tool into the front (mating end) of the connector
cavity until it rests on the cavity shoulder (1). 5. Gently pull on the wire to remove the terminal
through the back of the connector (2).
IMPORTANT: Never use force to remove a terminal from a connector.
6. Inspect the terminal and connector for damage. Repair as necessary. Refer to Repairing
Connector Terminals. See: General Electrical Diagnostic
Procedures/Wiring Repairs/Connector Repairs/Repairing Connector Terminals
7. Reform the lock tang (2) and reset terminal in connector body. 8. Close secondary locks and join
connector halves. 9. Verify that circuit is complete and working satisfactorily.
10. Perform system check.
General Information
The Wiring Repairs contains the following types of wiring repair information. Using these elements
together will make wiring repair faster and easier:
- Circuit Protection - Fuses
- Circuit Protection - Circuit Breakers
- Circuit Protection - Fusible Links
- Repairing Damaged Wire Insulation
- Splicing Copper Wire Using Splice Clips
- Splicing Copper Wire Using Splice Sleeves
- Splicing Twisted or Shielded Cable
- Splicing Inline Harness Diodes
- Heated Oxygen Sensor (HO2S) Wiring Repairs
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Diagram Information and Instructions > Page 10305
- SIR/SRS Wiring Repairs
- Flat Wire Repairs
Repairing Damaged Wire Insulation
If the conductive portion of the wire is not damaged, locate the problem and apply tape around the
wire. If the damage is more extensive, replace the faulty segment of the wire. Refer to Splicing
Copper Wire Using Splice Clips and follow the instruction to repair the wire. See: General Electrical
Diagnostic Procedures/Wiring Repairs/Typical Electrical Repairs/Splicing Copper Wire Using Splice
Clips
SIR/SRS Connector (Plastic Body and Terminal Metal Pin) Repair
Use the connector repair assembly packs in order to repair the damaged SIR/SRS wire harness
connectors and the terminals. Do not use the connector repair assembly pack in order to repair the
pigtails. These kits include an instruction sheet and the sealed splices.
Use the sealed splices in order to splice the new wires, connectors, and terminals to the harness.
The splice crimping tool is color keyed in order to match the splices from the J 38125-B. You must
use the splice crimping tool in order to apply these splices.
The terminals in the SIR/SRS system are made of a special metal. This metal provides the
necessary contact integrity for the sensitive, low energy circuits. These terminals are only available
in the connector repair assembly packs. Do not substitute any other terminals for those in the
assembly packs.
If the individual terminals are damaged on the sensing and diagnostic module (SDM) harness
connector, use 1 of the following 2 components in order to replace the SDM harness connector:
- The SDM harness connector pigtail assembly
- The SDM harness connector replacement kit
If the individual terminals are damaged on any other SIR/SRS connection, use the appropriate
connector repair assembly pack in order to replace the entire connection. Replace the entire
SIR/SRS wiring harness, if needed, in order to maintain Restraint Systems/SRS circuit integrity.
SIR/SRS System Wire Splice Repair
Apply a new splice (not sealed) from the J 38125-B if damage occurs to any of the original
equipment splices (3 wires or more) in the SIR/SRS wiring harness. Carefully follow the instructions
included in the kit for proper splice clip application.
Connector Position Assurance (CPA) The connector position assurance (CPA) is a small plastic
insert that fits through the locking tabs of all the SIR/SRS system electrical connectors. The CPA
ensures that the connector halves cannot vibrate apart. You must have the CPA in place in order to
ensure good contact between the SIR/SRS mating terminals.
Terminal Position Assurance (TPA) The terminal position assurance (TPA) insert resembles the
plastic combs used in the control module connectors. The TPA keeps the terminal securely seated
in the connector body. Do not remove the TPA from the connector body unless you remove a
terminal for replacement.
SIR/SRS Wire Pigtail Repair
IMPORTANT: Do not make wire, connector, or terminal repairs on components with wire pigtails.
A wire pigtail is a wire or wires attached directly to the device (not by a connector). If a wiring pigtail
is damaged, you must replace the entire component (with pigtail). The inflatable restraint steering
wheel module coil is an example of a pigtail component.
SIR/SRS Wire Repair
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
IMPORTANT: Refer to Wiring Repairs in order to determine the correct wire size for the circuit you
are repairing. You must obtain this information in order to ensure circuit integrity.
If any wire except the pigtail is damaged, repair the wire by splicing of wire of the same gage size
(0.5 mm, 0.8 mm, 1.0 mm etc.).
Use the sealed splices and splice crimping tool from the J 38125-8. Use the following wiring repair
procedures in order to ensure the integrity of the sealed splice.
IMPORTANT: You must perform the following procedures in the listed order. Repeat the procedure
if any wire strands are damaged. You must obtain a clean strip with all of the wire strands intact.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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1. Open the harness by removing any tape:
- Use a sewing seam ripper (available from sewing supply stores) in order to cut open the harness
in order to avoid wire insulation damage.
- Use the crimp and sealed splice sleeves on all types of insulation except tefzel and coaxial.
- Do not use the crimp and sealed splice sleeve to form a splice with more than 2 wires coming
together.
2. Cut as little wire off the harness as possible. You may need the extra length of wire in order to
change the location of a splice.
Adjust splice locations so that each splice is at least 40 mm (1.5 in) away from the other splices,
harness branches, or connectors.
3. Strip the insulation:
- When adding a length of wire to the existing harness, use the same size wire as the original wire.
- Perform one of the following items in order to find the correct wire size: Find the wire on the schematic and convert the metric size to the equivalent AWG size.
- Use an AWG wire gage.
- If you are unsure of the wire size, begin with the largest opening in the wire stripper and work
down until achieving a clean strip of the insulation.
- Strip approximately 7.5 mm (0.313 in) of insulation from each wire to be spliced.
- Do not nick or cut any of the strands. Inspect the stripped wire for nicks or cut strands.
- If the wire is damaged, repeat this procedure after removing the damaged.
4. Select the proper sealed splice sleeve according to the wire size. Refer to the table at the
beginning of the repair procedure for the color coding of
the splice sleeves and the crimp tool nests.
5. Use the Splice Crimp Tool from the J 38125-B in order to position the splice sleeve in the proper
color nest of the Splice Crimp Tool.
6. Place the splice sleeve in the nest. Ensure that the crimp falls midway between the end of the
barrel and the stop. The sleeve has a stop (3) in the
middle of the barrel (2) in order to prevent the wire (1) from going further. Close the hand crimper
handles slightly in order to firmly hold the splice sleeve in the proper nest.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Diagram Information and Instructions > Page 10307
7. Insert the wire into the splice sleeve barrel until the wire hits the barrel stop. 8. Tightly close the
handles of the crimp tool until the crimper handles open when released.
The crimper handles will not open until you apply the proper amount of pressure to the splice
sleeve. Repeat steps 4 and 5 for the opposite end of the splice.
9. Using the heat torch, apply heat to the crimped area of the barrel.
10. Gradually move the heat barrel to the open end of the tubing:
- The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Copper Wire Using Splice Clips
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Wire Size Conversion
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original (except fusible link).
- The wire's insulation must have the same or higher temperature rating. Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced.
5. Select the proper clip to secure the splice. Follow the instructions in the J 38125-B in order to
determine the proper clip size crimp tool and anvil. 6. Overlap the 2 stripped wire ends and hold
them between thumb and forefinger.
7. Center the splice clip (2) over the stripped wires (1) and hold the clip in place.
- Ensure that the wires extend beyond the clip in each direction.
- Ensure that no insulation is caught under the clip.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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8. Center the crimp tool over the splice clip and wires. 9. Apply steady pressure until the crimp tool
closes. Ensure that no strands of wire are cut.
10. Crimp the splice on each end (2).
11. Apply 60/40 rosin core solder to the opening in the back of the clip. Follow the manufacturer's
instructions for the solder equipment.
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12. Tape the splice. Roll on enough tape in order to duplicate the thickness of the insulation on the
existing wires.
13. Additional tape can be applied to the wire if the wire does not belong in a conduit or another
harness covering. Use a winding motion in order to
cover the first piece of tape.
Splicing Copper Wire Using Splice Sleeves
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
Use crimp and seal splice sleeves to form a one-to-one splice on all types of insulation except
tefzel and coaxial to form a one-to-one splice. Use tefzel and coaxial where there is special
requirements such as moisture sealing. Follow the instructions in order to splice copper wire using
crimp and seal splice sleeves.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the desired wire.
2. Cut the wire.
- Cut as little wire off the harness as possible.
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Component Information > Diagrams > Diagram Information and Instructions > Page 10311
- Ensure that each splice is at least 40 mm (1.5 in) away from other splices, harness branches and
connectors. This helps prevent moisture from bridging adjacent splices and causing damage.
3. Select the proper size and type of wire.
- The wire must be of equal or greater size than the original.
- The wire's insulation must have the same or higher temperature rating (4). Use general purpose insulation for areas that are not subject to high temperatures.
- Use a cross-linked polyethylene insulated wire for areas where high temperatures are expected.
IMPORTANT: Use cross-linked polyethylene wire to replace PVC, but do not replace cross-linked
polyethylene with PVC.
Cross-linked polyethylene wire is not fuel resistant. Do not use to replace wire where there is the
possibility of fuel contact.
4. Strip the insulation.
- Select the correct size opening in the wire stripper or work down from the largest size.
- Strip approximately 7.5 mm (5/16 in) of insulation from each wire to be spliced (1).
5. Select the proper splice sleeve (2) and the required crimp nest tool, refer to the Crimp and Seal
Splice Table. 6. Place the nest tool in the J 38125-B crimp tool. 7. Place the splice sleeve in the
crimp tool nest so that the crimp falls at point 1 on the splice. 8. Close the hand crimper handles
slightly in order to hold the splice sleeve firmly in the proper crimp tool nest. 9. Insert the wires into
the splice sleeve until the wire hits the barrel stop. The splice sleeve has a stop in the middle of the
barrel in order to prevent
the wire from passing through the splice (3).
10. Close the handles of the J 38125-B until the crimper handles open when released. The crimper
handles will not open until the proper amount of
pressure is applied to the splice sleeve.
11. Shrink the insulation around the splice.
- Using the heat torch apply heat to the crimped area of the barrel.
- Gradually move the heat barrel to the open end of the tubing. The tubing will shrink completely as the heat is moved along the insulation.
- A small amount of sealant will come out of the end of the tubing when sufficient shrinkage is
achieved.
Splicing Twisted or Shielded Cable
Twisted/shielded cable is used in order to protect wiring from electrical noise. Two-conductor cable
of this construction is used between the radio and the Delco-Bose(R) speaker/amplifier units and
other applications where low level, sensitive signals must be carried. Follow the instructions in
order to repair the twisted/shielded cable.
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1. Remove the outer jacket (1). Use care not to cut into the drain wire of the MYLAR tape. 2.
Unwrap the tape. Do not remove the tape. Use the tape in order to rewrap the twisted conductors
after the splice is made.
3. Prepare the splice. Untwist the conductors and follow the splicing instructions for copper wire.
Staggering the splices by 65 mm is recommended.
IMPORTANT: Apply the MYLAR tape with the aluminum side inward. This ensures good electrical
contact with the drain wire.
4. Re-assemble the cable.
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- Rewrap the conductors with the MYLAR tape.
- Use caution not to wrap the drain wire in the tape (1).
- Follow the splicing instructions for copper wire and splice the drain wire.
- Wrap the drain wire around the conductors and tape with MYLAR tape.
5. Tape over the entire cable. Use a winding motion when you apply the tape.
Splicing Inline Harness Diodes
Many vehicle electrical systems use a diode to isolate circuits and protect the components from
voltage spikes. When installing a new diode use the following procedure.
1. Open the harness.
- If the harness is taped, remove the tape.
- To avoid wiring insulation damage, use a sewing ripper in order to cut open the harness.
- If the harness has a black plastic conduit, pull out the diode.
2. If the diode is taped to the harness, remove all of the tape. 3. Check and record the current flow
direction and orientation of diode. 4. Remove the inoperative diode from the harness with a suitable
soldering tool.
IMPORTANT: If the diode is located next to a connector terminal remove the terminal(s) from the
connector to prevent damage from the soldering tool.
5. Carefully strip away insulation next to the old soldered portion of the wire(s). Do not remove any
more than is needed to attach the new diode. 6. Check current flow direction of the new diode,
being sure to install the diode with correct bias. Reference the appropriate wiring schematic to
obtain the correct diode installation position.
7. Attach the new diode to the wire(s) using 60/40 rosin core solder. Before soldering attach some
heat sinks (aluminum alligator clips) across the
diode wire ends to protect the diode from excessive heat. Follow the manufacturer's instruction for
the soldering equipment.
8. Reinstall terminal(s) into the connector body if previously removed.
IMPORTANT: To prevent shorts to ground and water intrusion, completely cover all exposed wire
and diode attachment points with tape.
9. Tape the diode to the harness or connector using electrical tape.
Heated Oxygen Sensor (HO2S) Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair Kit
NOTE: Do not solder repairs under any circumstances as this could result in the air reference being
obstructed.
If the heated oxygen sensor pigtail wiring, connector, or terminal is damaged the entire oxygen
sensor assembly must be replaced. Do not attempt to repair the wiring, connector, or terminals. In
order for the sensor to function properly it must have a clean air reference. This clean air reference
is obtained by way of the oxygen sensor signal and heater wires.
Any attempt to repair the wires, connectors or terminals could result in the obstruction of the air
reference and degrade oxygen sensor performance.
The following guidelines should be used when servicing the heated oxygen sensor:
- Do not apply contact cleaner or other materials to the sensor or vehicle harness connectors.
These materials may get into the sensor, causing poor
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performance. Also, the sensor pigtail and harness wires must not be damaged in such a way that
the wires inside are exposed. This could provide a path for foreign materials to enter the sensor
and cause performance problems.
- Neither the sensor nor vehicle lead wires should be bent sharply or kinked. Sharp bends, kinks,
etc., could block the reference air path through the lead wire.
- Do not remove or defeat the oxygen sensor ground wire (where applicable). Vehicles that utilize
the ground wire sensor may rely on this ground as the only ground contact to the sensor. Removal
of the ground wire will also cause poor engine performance.
- To prevent damage due to water intrusion, be sure that the peripheral seal remains intact on the
vehicle harness connector.
The engine harness may be repaired using the J 38125-B.
SIR/SRS Wiring Repairs
TOOLS REQUIRED
J 38125-B Terminal Repair kit
The supplemental inflatable restraint (SIR) system/supplemental restraint system (SRS) requires
special wiring repair procedures due to the sensitive nature of the circuitry. Follow the specific
procedures and instructions when working with the SIR/SRS system wiring, and the wiring
components (such as connectors and terminals).
IMPORTANT: Do not use the terminals in the kit in order to replace damaged SIR/SRS system
terminals unless specifically indicated by the terminal package.
The tool kit J 38125-B contains the following items:
- Special sealed splices - in order to repair the SIR/SRS system wiring
- A wire stripping tool
- A special crimping toot
- A heat torch
- An instruction manual
The sealed splices have the following 2 critical features:
- A special heat shrink sleeve environmentally seals the splice. The heat shrink sleeve contains a
sealing adhesive inside.
- A cross hatched (knurled) core crimp provides necessary contact integrity for the sensitive, low
energy circuits.
The J 38125-B also serves as a generic terminal repair kit. The kit contains the following items:
- A large sampling of common electrical terminals
- The correct tools in order to attach the terminals to the wires
- The correct tools in order to remove the terminals from the connectors
Flat Wire Repairs
NOTE: The flat wire within the flex wiring harness is not serviceable. If an open or short exists
within the flex wiring harness the complete harness must be replaced.
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Component Information > Diagrams > Diagram Information and Instructions > Page 10315
Equivalents - Decimal And Metric Part 1
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Equivalents - Decimal And Metric Part 2
Arrows and Symbols
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
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Component Information > Diagrams > Diagram Information and Instructions > Page 10317
Various symbols are used in order to describe different service operations.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Diagram Information and Instructions > Page 10318
Conversion - English/Metric
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Diagram Information and Instructions > Page 10319
Steering Wheel Controls Schematics: Steering Wheel Controls
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Page 10320
Steering Mounted Controls Transmitter: Description and Operation
STEERING WHEEL CONTROLS (SWC)
PROG
Press this button to play a station you have programmed on the radio preset buttons on the
selected band. If a cassette tape is playing, press this button to play the other side of the tape. If a
compact disc is playing in the console-mounted CD changer, press this button to go to the next
available CD.
SEEK
Press the up arrow to tune to the next radio station and the down arrow to tune to the previous
radio station. If a cassette tape or compact disc is playing, the player will advance forward with the
up arrow to the next track or backward with the down arrow to the previous track.
MUTE
Press this button to silence the system. Press it again to turn on the sound.
VOL
Press the up or down arrow to increase or decrease volume.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Page 10321
Steering Mounted Controls Transmitter: Testing and Inspection
Steps 1-7
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Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Mounted Controls Transmitter >
Component Information > Diagrams > Page 10322
Steps 8-10
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering
Wheel
Steering Shaft: Customer Interest Steering - Underhood Clunk Heard/Felt in Steering Wheel
TECHNICAL
Bulletin No.: 00-02-35-003N
Date: March 26 2008
Subject: Clunking Noise Under Hood and Can Be Felt in Steering Wheel and/or Steering Column
(Replace Upper Intermediate Steering Shaft [I-Shaft] Assembly)
Models: 2002-2006 Cadillac Escalade Models 1999-2007 Chevrolet Silverado Models (Classic)
2000-2006 Chevrolet Suburban, Tahoe Models 2002-2006 Chevrolet Avalanche 1999-2007 GMC
Sierra Models (Classic) 2000-2006 GMC Yukon, Yukon XL Models 2003-2006 HUMMER H2
Attention:
This Service Bulletin DOES NOT include Mid-Size Utilities such as Buick Rainier, Chevrolet
TrailBlazer Models, GMC Envoy Models or Oldsmobile Bravada. Refer to Service Bulletin
02-02-35-006A or newer for Mid-Size Utilities.
Supercede:
This bulletin is being revised to add diagnostic information (refer to Diagnostic Tips) to check the
lower steering column bearing as a potential source of the noise. Please discard Corporate Bulletin
Number 00-02-35-003M (Section 02-Steering).
Condition
Some customers may comment on a clunk-type noise coming from under the hood that also can be
felt in the steering wheel. These conditions may be more noticeable when turning at low speeds on
rough road surfaces.
Diagnostic Tips
Use the information below to help diagnose the source of the noise.
^ The lower steering column bearing may create the same noise as the intermediate shaft. Before
replacing the I-shaft, verify the noise isn't being caused by movement from the lower steering
column bearing. Check the bearing for movement by pushing up and down on the I-shaft where it
attaches to the steering column.
^ Frame Snap and/or Popping Type Noise - A frame snap or popping type noise can be duplicated
on rough or smooth road surfaces with steering wheel input to the left or the right. This type of
noise can be HEARD and is typically louder with the windows rolled down. For additional
information refer to Corporate Bulletin Number 03-08-61-002F or newer - Snap/Popping Type
Noise Coming from Front of Vehicle (Remove Front Crossmember Change Fastener Orientation).
^ Intermediate Shaft Clunk - Intermediate shaft clunk is heard and FELT in the steering wheel
and/or steering column area typically while driving on rough road surfaces with steering wheel
input.
Correction
Important:
^ I-shaft P/N 19153614 has been designed to replace previous designed dampened and
non-dampened I-shafts. The physical difference in the yoke size will accommodate all vehicles
listed in this bulletin.
^ Due to the design of the new I-shaft, it is not possible to lubricate/grease the I-shaft.
Replace the steering column upper intermediate shaft with an improved design shaft that will
eliminate the clunk noise using the procedure listed below.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering
Wheel > Page 10331
1. Set the front wheels in the straight ahead position.
Notice:
On the 2002 and later model year vehicles the steering column LOCK was removed from the
steering column. It is critical that the J 42640 - Steering column Anti-Rotation Pin is used when
servicing steering columns on 2002 and later model year vehicles. Failure to use the J 42640 may
result in damage to the SIR coil.
2. Set the steering wheel in the LOCK position on 2001 and prior model year vehicles.
3. For 2002 and later vehicles install the J 42640 in the steering column lower access hole.
4. From under the hood remove the lower bolt that connects the upper intermediate shaft to the
steering gear coupling shaft.
5. Slide the shaft towards the dash in order to disengage the shaft from the steering gear coupling
shaft.
6. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the carpet away from the accelerator pedal position (APP) sensor.
2. Remove the two nuts retaining the accelerator pedal to the bulkhead.
3. Reposition the accelerator pedal out of the way so the intermediate shaft can be removed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering
Wheel > Page 10332
7. From inside the vehicle remove the upper bolt from the upper intermediate steering shaft (1) to
the steering column connection.
8. Remove the upper intermediate steering shaft assembly.
1. From inside the vehicle slide the shaft down and off the steering column.
2. From inside the vehicle slide the upper intermediate shaft through the dash boot seal and
remove the shaft from the vehicle.
9. Replace the upper intermediate shaft.
10. Install the upper intermediate steering shaft through the dash boot seal and slide the lower end
into the steering gear coupling shaft.
11. Raise the upper end of the intermediate steering shaft and install into the steering column shaft.
12. Install the upper bolt and nut.
Tighten
Tighten the bolt to 47 N.m (35 lb ft).
13. Install the lower bolt and nut.
Tighten
Tighten the bolt to 50 N.m (37 lb ft).
14. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the accelerator pedals into position on the bulkhead.
2. Install the two retaining nuts.
Tighten
Tighten the nuts to 20 N.m (15 lb ft).
3. Reposition the carpet into place.
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Customer Interest: > 00-02-35-003N > Mar > 08 > Steering - Underhood Clunk Heard/Felt in Steering
Wheel > Page 10333
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 00-02-35-003N > Mar > 08 > Steering - Underhood
Clunk Heard/Felt in Steering Wheel
Steering Shaft: All Technical Service Bulletins Steering - Underhood Clunk Heard/Felt in Steering
Wheel
TECHNICAL
Bulletin No.: 00-02-35-003N
Date: March 26 2008
Subject: Clunking Noise Under Hood and Can Be Felt in Steering Wheel and/or Steering Column
(Replace Upper Intermediate Steering Shaft [I-Shaft] Assembly)
Models: 2002-2006 Cadillac Escalade Models 1999-2007 Chevrolet Silverado Models (Classic)
2000-2006 Chevrolet Suburban, Tahoe Models 2002-2006 Chevrolet Avalanche 1999-2007 GMC
Sierra Models (Classic) 2000-2006 GMC Yukon, Yukon XL Models 2003-2006 HUMMER H2
Attention:
This Service Bulletin DOES NOT include Mid-Size Utilities such as Buick Rainier, Chevrolet
TrailBlazer Models, GMC Envoy Models or Oldsmobile Bravada. Refer to Service Bulletin
02-02-35-006A or newer for Mid-Size Utilities.
Supercede:
This bulletin is being revised to add diagnostic information (refer to Diagnostic Tips) to check the
lower steering column bearing as a potential source of the noise. Please discard Corporate Bulletin
Number 00-02-35-003M (Section 02-Steering).
Condition
Some customers may comment on a clunk-type noise coming from under the hood that also can be
felt in the steering wheel. These conditions may be more noticeable when turning at low speeds on
rough road surfaces.
Diagnostic Tips
Use the information below to help diagnose the source of the noise.
^ The lower steering column bearing may create the same noise as the intermediate shaft. Before
replacing the I-shaft, verify the noise isn't being caused by movement from the lower steering
column bearing. Check the bearing for movement by pushing up and down on the I-shaft where it
attaches to the steering column.
^ Frame Snap and/or Popping Type Noise - A frame snap or popping type noise can be duplicated
on rough or smooth road surfaces with steering wheel input to the left or the right. This type of
noise can be HEARD and is typically louder with the windows rolled down. For additional
information refer to Corporate Bulletin Number 03-08-61-002F or newer - Snap/Popping Type
Noise Coming from Front of Vehicle (Remove Front Crossmember Change Fastener Orientation).
^ Intermediate Shaft Clunk - Intermediate shaft clunk is heard and FELT in the steering wheel
and/or steering column area typically while driving on rough road surfaces with steering wheel
input.
Correction
Important:
^ I-shaft P/N 19153614 has been designed to replace previous designed dampened and
non-dampened I-shafts. The physical difference in the yoke size will accommodate all vehicles
listed in this bulletin.
^ Due to the design of the new I-shaft, it is not possible to lubricate/grease the I-shaft.
Replace the steering column upper intermediate shaft with an improved design shaft that will
eliminate the clunk noise using the procedure listed below.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 00-02-35-003N > Mar > 08 > Steering - Underhood
Clunk Heard/Felt in Steering Wheel > Page 10339
1. Set the front wheels in the straight ahead position.
Notice:
On the 2002 and later model year vehicles the steering column LOCK was removed from the
steering column. It is critical that the J 42640 - Steering column Anti-Rotation Pin is used when
servicing steering columns on 2002 and later model year vehicles. Failure to use the J 42640 may
result in damage to the SIR coil.
2. Set the steering wheel in the LOCK position on 2001 and prior model year vehicles.
3. For 2002 and later vehicles install the J 42640 in the steering column lower access hole.
4. From under the hood remove the lower bolt that connects the upper intermediate shaft to the
steering gear coupling shaft.
5. Slide the shaft towards the dash in order to disengage the shaft from the steering gear coupling
shaft.
6. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the carpet away from the accelerator pedal position (APP) sensor.
2. Remove the two nuts retaining the accelerator pedal to the bulkhead.
3. Reposition the accelerator pedal out of the way so the intermediate shaft can be removed.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 00-02-35-003N > Mar > 08 > Steering - Underhood
Clunk Heard/Felt in Steering Wheel > Page 10340
7. From inside the vehicle remove the upper bolt from the upper intermediate steering shaft (1) to
the steering column connection.
8. Remove the upper intermediate steering shaft assembly.
1. From inside the vehicle slide the shaft down and off the steering column.
2. From inside the vehicle slide the upper intermediate shaft through the dash boot seal and
remove the shaft from the vehicle.
9. Replace the upper intermediate shaft.
10. Install the upper intermediate steering shaft through the dash boot seal and slide the lower end
into the steering gear coupling shaft.
11. Raise the upper end of the intermediate steering shaft and install into the steering column shaft.
12. Install the upper bolt and nut.
Tighten
Tighten the bolt to 47 N.m (35 lb ft).
13. Install the lower bolt and nut.
Tighten
Tighten the bolt to 50 N.m (37 lb ft).
14. For vehicles equipped with adjustable foot pedals perform the following steps:
1. Reposition the accelerator pedals into position on the bulkhead.
2. Install the two retaining nuts.
Tighten
Tighten the nuts to 20 N.m (15 lb ft).
3. Reposition the carpet into place.
Parts Information
Warranty Information
For vehicles repaired under warranty use, the table.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 00-02-35-003N > Mar > 08 > Steering - Underhood
Clunk Heard/Felt in Steering Wheel > Page 10341
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures
Steering Shaft: All Technical Service Bulletins Steering - Revised Service Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10346
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10347
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10348
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10349
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10350
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10351
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10352
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Technical Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised
Service Procedures > Page 10353
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures
Steering Shaft: All Technical Service Bulletins Steering - Revised Service Procedures
Bulletin No.: 03-02-36-002
Date: July 30, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Procedure and Steering Wheel Position Sensor Centering Procedure
Models: 1998-2003 Buick LeSabre, Park Avenue 1998-2003 Cadillac DeVille, Seville 2003 Cadillac
CTS 1998-2003 Chevrolet Corvette 1998 Oldsmobile Achieva 1998-2002 Oldsmobile Intrigue
1998-2003 Oldsmobile Aurora 1999-2003 Oldsmobile Alero 1998-2003 Pontiac Bonneville, Grand
Am 1998-2000 Chevrolet C/K Pickup Models 1998-2003 Chevrolet Suburban, Tahoe 1999-2003
Chevrolet Silverado 2002-2003 Chevrolet Avalanche 1998-1999 GMC Suburban 1998-2000 GMC
C/K Pickup Models 1998-2003 GMC Yukon 1999-2003 GMC Sierra 2000-2003 GMC Yukon
Denali, Yukon XL 2003 GMC Sierra Denali
This bulletin is being issued to revise the Steering Wheel Position Sensor or Steering Shaft Lower
Bearing Replacement procedure in the Variable Effort Steering (1998-2001 model years) or
Steering Wheel and Column (2002-2003 model years) and add the Steering Wheel Position Sensor
Centering procedure in the Steering Wheel and Column sub-sections of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Steering Wheel Position Sensor or Steering Shaft Lower Bearing Replacement
Removal Procedure
Caution:
Refer to SIR Caution in Cautions and Notices.
1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
2. Remove the steering column from the vehicle. Refer to Steering Column Replacement.
3. Remove the following from the steering shaft:
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10359
3.1. steering shaft seal (7)
3.2. sensor retainer (6)
3.3. steering wheel position sensor (5), refer to Steering Wheel Position Sensor Centering.
3.4. 2 lower spring retainers (4)
3.5. lower bearing spring (3)
3.6. lower bearing seat (2)
3.7. adapter and bearing assembly (1)
Installation Procedure
1. Install the following onto the steering shaft:
1.1. adapter and bearing assembly (1)
1.2. lower bearing seat (2)
1.3. lower bearing spring (3)
1.4. 2 lower spring retainers (4)
1.5. steering wheel position sensor (5) refer to Steering Wheel Position Sensor Centering.
1.6. sensor retainer (6)
1.7. steering shaft seal (7)
1.8. Enable the SIR system. Refer to in SIR.
2. Install the steering column to the vehicle. Refer to Steering Column Replacement.
3. Enable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.
Steering Wheel Position Sensor Centering
Removal Procedure
Important:
Identify the type of steering wheel position sensor from the illustrations below BEFORE removing
the sensor from the steering column. Once you have identified the steering wheel position sensor,
follow the instructions listed in the removal procedure.
1. Verify the type of steering wheel position sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10360
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on the right.
Important:
If reusing the existing sensor, you do not have to align the sensor before removal. Centering is not
required when it is time to reinstall.
3. Remove the connector from the sensor.
4. Remove the sensor (1) from the adapter and bearing assembly.
5. To install the sensor, proceed to step 1 in the installation section.
6. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (2)
^ A pin hole (1) for centering the pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
Important:
If reusing the existing sensor, you must make an alignment mark on the rotor flange cuff (3) before
removing the sensor. Failure to do so will cause misalignment when installing the sensor. A new
sensor will be required if misaligned.
7. Make an alignment mark on the flush rotor flange cuff (3).
8. Remove the connector from the sensor.
9. Remove the sensor from the adapter and bearing assembly.
10. To install the sensor, proceed to step 5 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10361
11. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
12. Remove the connector from the sensor.
13. Remove the sensor from the adapter and bearing assembly.
14. To install the sensor, proceed to step 9 in the installation section.
15. From the technicians point of view, the FRONT of the sensor will have:
^ A raised rotor flange cuff (3)
^ An alignment mark (2) on the rotor flange cuff (3) for installation
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ A sensor clip in FRONT of the sensor
16. Remove the connector from the sensor.
17. Remove the sensor clip from the sensor.
18. Remove the sensor from the adapter and bearing assembly.
19. To install the sensor, proceed to step 13 in the installation section.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10362
20. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (3)
^ A pin hole (1) for the centering pin (note location of the pin hole)
^ An alignment mark (2) on the flush rotor flange cuff (3) for installation
21. Remove the connector from the sensor.
22. Remove the sensor from the adapter and bearing assembly.
23. To install the sensor, proceed to step 17 in the installation section.
24. From the technicians point of view, the FRONT of the sensor will have:
^ A flush rotor flange cuff (4)
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ An alignment mark (3) on the flush rotor flange cuff (4) for installation
^ A foam ring (1)
25. Remove the connector from the sensor.
26. Remove the sensor from the adapter and bearing assembly.
27. To install the sensor, proceed to step 21 in the installation section.
Installation Procedure
Important:
If reusing the existing sensor, no centering of the sensor is required.
1. If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin
until the sensor is seated.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10363
2. From the technicians point of view, the FRONT of the sensor (1) connector will be on your right.
From the technicians point of view, the BACK of the sensor (2) connector will be on your left.
3. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
4. Install the connector to the sensor.
5. From the technicians point of view, the FRONT of the sensor will have:
^ A foam ring (4)
^ A pin hole (7) for the centering pin (note location of the pin hole)
^ A flushed rotor flange cuff (6)
^ An alignment mark (5) for installation
6. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ A foam ring (3)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
^ A view of the inside of the connector
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
7. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
8. Install the connector to the sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10364
9. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (5)
^ An alignment mark (4) for installation
10. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats(1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
11. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
12. Install the connector to the sensor.
13. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A raised rotor flange cuff (4)
^ An alignment mark (3) for installation
14. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the raised rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10365
15. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
16. Install the connector to the sensor.
17. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (2) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (4)
^ An alignment mark (3) for installation
18. From the technicians point of view, the BACK of the sensor will have an alignment tab (1) for
installation. This sensor does not have double D flats.
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
19. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
20. Install the connector to the sensor.
21. From the technicians point of view, the FRONT of the sensor will have:
^ A pin hole (3) for the centering pin (note location of the pin hole)
^ A flush rotor flange cuff (5)
^ An alignment mark (4) for installation
^ A foam ring (6)
22. From the technicians point of view, the BACK of the sensor will have:
^ Double D flats (1)
^ An alignment tab (2) for installing into the adapter and bearing assembly.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > All Other Service Bulletins for Steering Shaft: > 03-02-36-002 > Jul > 03 > Steering - Revised Service
Procedures > Page 10366
Important:
If reusing the existing sensor, you must align the marks on the flush rotor flange cuff before
installation. The alignment mark must stay aligned until the sensor is seated into the adapter and
bearing assembly.
If installing a new sensor, it will come with a pin installed in the sensor. Do not remove the pin until
the sensor is seated. If the new sensor did not come with a pin installed, you must reorder a new
sensor.
23. Looking at the FRONT of the sensor, align the sensor with the steering shaft and install into the
adapter and bearing assembly.
24. Install the connector to the sensor.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Page 10367
Steering Shaft: Specifications
Intermediate Shaft Coupler Bolt
............................................................................................................................................................
50 Nm (37 inch lbs.) Intermediate Shaft Pinch Bolt .............................................................................
...................................................................................... 47 Nm (35 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Shaft > Component Information > Technical
Service Bulletins > Page 10368
Steering Shaft: Service and Repair
"For information regarding this component please refer to steering column service and repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Wheel > Component Information >
Technical Service Bulletins > Steering Wheel - Removal Procedure Revision
Steering Wheel: Technical Service Bulletins Steering Wheel - Removal Procedure Revision
Bulletin No.: 03-02-35-006
Date: December 02, 2003
SERVICE MANUAL UPDATE
Subject: Revised Steering Wheel Replacement Procedure
Models: 2002 Cadillac Escalade, Escalade EXT 2001-2002 Chevrolet Silverado, Suburban, Tahoe
2002 Chevrolet Avalanche 2002-2003 Chevrolet TrailBlazer, TrailBlazer EXT 2003 Chevrolet
Express, SSR 2001-2002 GMC Sierra, Yukon, Yukon Denali, Yukon XL 2002-2003 GMC Envoy,
Envoy XL 2003 GMC Savana 2002-2003 Oldsmobile Bravada 2003 HUMMER H2 2003 Isuzu
Ascender
This bulletin is being issued to revise the Steering Wheel Replacement procedure in the Steering
Wheel and Column sub-section of the Service Manual. Please replace the current information in
the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Steering Wheel > Component Information >
Technical Service Bulletins > Steering Wheel - Removal Procedure Revision > Page 10373
The steering wheel puller legs currently recommended in the Service Manual for use with steering
wheel puller J 1859-A are incorrect and will not work on these vehicles. The correct steering wheel
puller legs that should be used with steering wheel puller J 1859-A are J 36541-A or J 42578. The
Steering Wheel Replacement procedure has been updated with the correct steering wheel puller
tool usage. Refer to the table for SI Document ID numbers.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Tie Rod > Component Information > Technical
Service Bulletins > Steering - New Inner Tie Rod Service Parts
Tie Rod: Technical Service Bulletins Steering - New Inner Tie Rod Service Parts
Bulletin No.: 03-02-34-001A
Date: October 06, 2003
INFORMATION
Subject:
Inner Tie Rod Released for Service
Models: 2002-2004 Cadillac Escalade, Escalade EXT 1500 Series 2003 Cadillac Escalade ESV
1500 Series 1999-2004 Chevrolet Silverado 4WD 1500 Series 2000-2004 Chevrolet Suburban,
Tahoe 1500 Series Models 2002-2004 Chevrolet Avalanche 1500 Series Models 1999-2004 GMC
Sierra 4WD 1500 Series Models 2000-2004 GMC Yukon, Yukon XL, Yukon Denali 1500 Series
Models 2003-2004 HUMMER H2
Supercede:
This bulletin is being revised to correct the model information. Please discard Corporate Bulletin
Number 03-02-34-001 (Section 02 - Steering).
This bulletin is being issued to inform dealers that the inner tie rod can now be serviced separately
on vehicles that use steering linkage relay rod kit, P/N 12471375 or P/N 89040375. In cases where
only the inner tie rod is required, use P/N 26059210 and follow the Tie Rod Replacement - Inner
procedure in the Steering Linkage (Non-Rack and Pinion) subsection.
Parts are currently available from GMSPO.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Tie Rod > Component Information > Technical
Service Bulletins > Page 10378
Tie Rod: Specifications
Tie Rod Jam Nut ..................................................................................................................................
..................................................... 68 Nm (50 ft. lbs.) Tie Rod to Steering Knuckle Nut
.............................................................................................................................................................
45 Nm (33 ft. lbs.) Outer Tie Rod Jam Nut ..........................................................................................
................................................................................... 68 Nm (50 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Tie Rod > Component Information > Technical
Service Bulletins > Page 10379
Tie Rod: Service and Repair
Tie Rod Replacement
Tools Required ^
J24319-B Universal Steering Linkage Puller
^ J29193 Steering Linkage Installer-12 mm
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting.
Important: Use the J24319-B in order to separate all the tie rods and ball joints.
2. Remove the nut (2) from the outer tie rod ball stud (3).
3. Use the J24319-B in order to remove the outer tie rod ball stud from the steering knuckle.
Important: Do not reuse the nut.
4. Remove the tie rod end from the shaft by loosening the jam nut.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Tie Rod > Component Information > Technical
Service Bulletins > Page 10380
5. Remove the outer tie rod end from the relay rod. 6. Inspect the shaft (6) for bent or damaged
threads. 7. Clean the tapered surface of the steering knuckle (1).
Installation Procedure
1. Lubricate the tie rod threads with chassis lubricant.
2. Install the tie rod end (4) to the shaft (6). 3. Install the outer tie rod ball stud (3) to the steering
knuckle (1).
Notice: Refer to Fastener Notice in Service Precautions.
4. Use the J29193 in order to install the outer tie rod ball stud.
Tighten the J29193 to 54 Nm (40 ft. lbs.) in order to seat the tapers.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Steering > Tie Rod > Component Information > Technical
Service Bulletins > Page 10381
5. Install the new prevailing torque nut (2) to the outer rod ball stud (3).
Tighten the nut to 45 Nm (33 ft. lbs.).
6. Adjust the front toe. 7. Tighten the jam nut (5).
Tighten the nut to 68 Nm (50 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Ball Joint > Component Information >
Specifications
Ball Joint: Specifications
Lower Ball Joint to Lower Control Arm Nuts
.......................................................................................................................................... 70 Nm (52
ft. lbs.) Lower Ball Joint Stud Nut ........................................................................................................
.............................................................. 100 Nm (74 ft. lbs.) Upper Ball Joint Stud Nut ......................
.................................................................................................................................................. 50 Nm
(37 ft. lbs.) Joint Wear Limit .................................................................................................................
................................................................. 3.18 mm (0.125 inch)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Ball Joint > Component Information >
Specifications > Page 10386
Ball Joint: Testing and Inspection
Ball Joint Inspection
Tools Required ^
J8001 Dial Indicator
Important: ^
The vehicle must rest on a level surface.
^ The vehicle must be stable. Do not rock the vehicle on the jack stands.
^ The upper control arm bumper must not contact the frame.
1. Raise and support the vehicle with safety stands. Refer to Vehicle Lifting. 2. Support the lower
control arm with a jack stand, as far outboard as possible, near the lower ball joint.
Important: If a seal is cut or torn, replace the ball joint.
3. Wipe the ball joints clean. Check the seals for cuts or tears. 4. Check the wheel bearings for
looseness. If looseness in the wheel bearings is present, refer to Wheel Bearings Diagnosis
(Sealed). 5. Check the ball joints for horizontal looseness.
5.1. Position the J8001 dial indicator against the lowest outboard point on the wheel rim.
5.2. Rock the wheel in and out while reading the dial indicator. This shows horizontal looseness in
both joints.
5.3. The dial indicator reading should be no more than 3.18 mm (0.125 inch). If the reading is too
high, check the lower ball joints for vertical looseness.
6. Check the lower ball joints for wear and for vertical looseness using the following procedure:
6.1. Inspect by sight the lower ball joint for wear. The position of the housing into which the grease
fitting is threaded indicates wear. This round housing projects 1.27 mm (0.050 inch) beyond the
surface of the lower ball joint cover on a new ball joint. Under normal wear, the surface of the lower
ball joint housing retreats inward very slowly.
6.2. First observe, then scrape a scale, a screwdriver, or a fingernail across the cover. If the round
housing is flush with or inside of the cover surface, replace the lower ball joint.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Ball Joint > Component Information >
Specifications > Page 10387
7. Place a J8001 dial indicator (1) against the spindle in order to show vertical movement.
8. Pry between the lower control arm (2) and the outer bearing race (1) while reading the dial
indicator. This shows vertical looseness in the ball
joints. The lower ball joint is not preloaded and may show some looseness.
9. If the dial indicator reading is more than 3.18 mm (0.125 inch), replace the lower ball joint.
10. If the lower ball joint is within specifications, and there is too much horizontal looseness, check
the upper control arm for wear. If you find any
looseness or can twist the stud with your fingers, replace the upper control arm.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Ball Joint > Component Information > Service
and Repair > Lower Ball Joint Replacement (Coil Spring Suspension)
Ball Joint: Service and Repair Lower Ball Joint Replacement (Coil Spring Suspension)
Lower Ball Joint Replacement (Coil Spring Suspension)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Remove the lower control arm. 4. Secure the lower control arm in a bench vice or equivalent. 5.
Center punch the rivet heads. 6. Drill out the rivets. 7. Remove the lower ball joint.
Installation Procedure
1. Install the ball joint to the lower control arm. 2. Install the replacement bolts to the lower control
arm.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the nuts to the bolts.
Tighten the nuts to 70 Nm (52 ft. lbs.).
4. Remove the lower control arm from the bench vice. 5. Install the lower control arm. 6. Install the
tire and wheel tire assembly. 7. Remove the safety stands. 8. Lower the vehicle. 9. Verify the wheel
alignment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Ball Joint > Component Information > Service
and Repair > Lower Ball Joint Replacement (Coil Spring Suspension) > Page 10390
Ball Joint: Service and Repair Lower Ball Joint Replacement (Torsion Bar Suspension)
Lower Ball Joint Replacement (Torsion Bar Suspension)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel assembly.
3. Remove the lower control arm. 4. Place the lower control arm in a bench vice. 5. Using a chisel,
remove the 4 securing crimps from the ball joint body, the 15 series only. 6. Using a press, remove
the ball joint from the lower control arm.
Installation Procedure
Important: Use the outer flange of the ball joint in order to press the ball joint into place.
1. Install the new ball joint using a press. 2. Place the lower control arm in a bench vice. 3. Using a
punch, install 4 crimps to the ball joint. Use the replaced ball joint as a reference, the 15-series
only. 4. Install the lower control arm. 5. Install the tire and wheel assembly. 6. Remove the safety
stands. 7. Lower the vehicle. 8. Verify the wheel alignment.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information >
Specifications
Control Arm: Specifications
Front
Upper Control Arm Nuts ......................................................................................................................
............................................. 190 Nm (140 ft.lbs.) Lower Control Arm to Frame Nuts
................................................................................................................................................... 150
Nm (110 ft. lbs.)
Rear
Lower Control Arm Bolt .......................................................................................................................
.............................................. 120 Nm (89 ft. lbs.) Upper Control Arm Bolt .........................................
............................................................................................................................ 105 Nm (77 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front
Control Arm: Service and Repair Front
Upper Control Arm Replacement
Upper Control Arm Replacement
Tools Required ^
J43631 Ball Joint Separator
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel.
3. Disconnect the Real Time Damping (RTD) link rod from the sensor, if equipped. 4. Remove the
retaining bolt for the brake hose and the wheel speed sensor brackets. 5. Remove the wheel drive
shaft. 6. Remove the nut at the upper ball joint. Discard the nut.
7. Disconnect the upper control arm from the steering knuckle using the J43631 (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10396
8. Remove the upper control arm nuts and the adjustment cams (2) for the 15 Series 2WD, 4WD,
and 25/35 Series 2WD). 9. Remove the upper control arm bolts (4) for the 15 Series 2WD, 4WD,
and 25/35 Series 2WD.
10. Remove the upper control arm nuts and the adjustment cams (2) for the 25/35 Series 4WD. 11.
Remove the upper control arm bolts (4) for the 25/35 Series 4WD. 12. Remove the upper control
arm.
Installation Procedure
1. Install the upper control arm.
2. Install the upper control arm bolts (4) for the 25/35 Series 4WD.
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the upper control arm nuts and the adjustment cams (2) 25/35 Series 4WD.
Tighten the nuts to 190 Nm (140 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10397
4. Install the upper control arm bolts (4) for the 15 Series 2WD, 4WD, and 25/35 Series 2WD. 5.
Install the upper control arm nuts and the adjustment cams (2) for the 15 Series 2WD, 4WD, and
25/35 Series 2WD.
Tighten the nuts to 190 Nm (140 ft. lbs.).
6. Connect the upper control arm to the steering knuckle. 7. Install the wheel drive shaft. 8. Install
the new nut to the upper ball joint stud.
Tighten the nut to 50 Nm (37 ft. lbs.).
9. Install the retaining bolts for the brake hose and wheel speed sensor brackets.
Tighten the bolts to 9 Nm (80 inch lbs.).
10. Connect the RTD link rod to the sensor, if equipped. 11. Install the tire and wheel. 12. Remove
the safety stands. 13. Lower the vehicle. 14. Verify the wheel alignment.
Lower Control Arm Replacement
Lower Control Arm Replacement
Tools Required ^
J43631 Ball Joint Remover
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel. 3. Remove
the stabilizer shaft links from the lower control arm. 4. Remove the shock absorber lower nut and
the bolt. 5. Remove the torsion bars. 6. Remove the wheel drive shaft. 7. Remove the lower ball
joint stud nut.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10398
8. Disconnect the lower ball joint stud from the steering knuckle using J43631 (1).
9. Remove the lower control arm nuts and the 15-series washers.
10. Remove the lower control arm bolts.
11. Remove the lower control arm nuts and the 25/35-series washers. 12. Remove the lower
control arm bolts. 13. Remove the lower control arm.
Installation Procedure
1. Install the lower control arm.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10399
2. Install the lower control arm 15-series bolts.
3. Install the lower control arm 25/35-series bolts.
4. Install the washers with the shoulder facing the arm.
Notice: Refer to Fastener Notice in Service Precautions.
5. Install the lower control arm retaining nuts.
Tighten the nuts to 150 Nm (110 ft. lbs.).
6. Install the wheel drive shaft. 7. Connect lower ball joint stud to the steering knuckle. 8. Install the
nut to the lower ball joint stud.
Tighten the nut to 100 Nm (74 ft. lbs.).
9. Install the torsion bars.
10. Install the shock absorber lower nut and bolt. 11. Install the stabilizer shaft links to the lower
control arm. 12. Install the tire and wheel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10400
13. Remove the safety stands. 14. Lower the vehicle. 15. Align the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10401
Control Arm: Service and Repair Rear
Rear Axle Upper Control Arm Replacement
Rear Axle Upper Control Arm Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Disconnect the Real Time Damping
(RTD) sensor (if equipped).
3. Remove the upper control arm retaining nut and bolt from the frame bracket.
4. Remove the upper control arm retaining nut and bolt from the axle bracket. 5. Remove the upper
control arm.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10402
1. Install the upper control arm. 2. Install the upper control arm retaining bolt and nut to the axle
bracket.
3. Install the upper control arm retaining bolt to the frame bracket.
Notice: Refer to Fastener Notice in Service Precautions.
Important: Do not tighten the nuts unless the suspension is at the curb height position.
4. Install the upper control arm retaining nut.
Tighten the upper control arm retaining bolts to 105 Nm (77 ft. lbs.).
5. Connect the (RTD) sensor (if equipped). 6. Lower the vehicle.
Rear Axle Lower Control Arm Replacement
Rear Axle Lower Control Arm Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting.
2. Remove the lower control arm retaining nuts. 3. Remove the lower control arm retaining bolt. 4.
Remove the lower control arm.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Control Arm > Component Information > Service
and Repair > Front > Page 10403
1. Install the lower control arm. 2. Install the lower control arm retaining bolts.
Notice: Refer to Fastener Notice in Service Precautions.
Important: Do not tighten the bolts unless the suspension is at the ride height.
3. Install the lower control arm retaining nut.
Tighten the lower control arm retaining bolts to 120 Nm (89 ft. lbs.).
4. Remove the rear axle support. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Cross-Member > Component Information >
Technical Service Bulletins > Body/Frame - Revised Crossmember/Body Bolt Service
Cross-Member: Technical Service Bulletins Body/Frame - Revised Crossmember/Body Bolt
Service
Bulletin No.: 05-08-61-005
Date: April 29, 2005
SERVICE MANUAL UPDATE
Subject: Revised Crossmember/Body Mount Bolt Installation Information
Models: 1999-2005 Cadillac Full-Size Pickup and Utility Models 1999-2005 Chevrolet Full-Size
Pickup and Utility Models 1999-2005 GMC Full-Size Pickup and Utility Models
This bulletin is being issued to revise all repair procedures that include reinstalling the front engine
crossmember-to-frame bolts or any body mount bolts in the Frame and Underbody sub-section of
the Service Manual. Please replace the current information in the Service Manual with the following
information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
Before reinstalling front engine crossmember-to-frame bolts or any body mount bolts, you must do
the following:
1. Remove all traces of the original thread locking material.
2. Clean the threads of the bolt with denatured alcohol, or equivalent, and allow to dry.
3. Apply Thread locker, P/N 12345493, (Canadian P/N 10953488).
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Cross-Member > Component Information >
Service and Repair > Engine Front Crossmember Replacement (4WD)
Cross-Member: Service and Repair Engine Front Crossmember Replacement (4WD)
Engine Front Crossmember Replacement (4WD)
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the differential carrier shield.
3. Remove the bolts retaining the crossmember to the frame.
4. Remove the crossmember from the vehicle.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Cross-Member > Component Information >
Service and Repair > Engine Front Crossmember Replacement (4WD) > Page 10410
1. Install the crossmember to the vehicle. 2. Perform the following procedure before installing the
bolts.
1. Remove all traces of the original adhesive patch. 2. Clean the threads of the bolt with denatured
alcohol or equivalent and allow to dry. 3. Apply Threadlocker GM P/N 12345493 (Canadian P/N
10953488).
Notice: Refer to Fastener Notice.
3. Install the bolts retaining the crossmember to the frame.
Tighten the crossmember retaining bolts to 120 N.m (88 lb ft).
4. Install the differential carrier shield. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Cross-Member > Component Information >
Service and Repair > Engine Front Crossmember Replacement (4WD) > Page 10411
Cross-Member: Service and Repair Transmission Support Replacement
Transmission Support Replacement
Removal Procedure
1. Raise the vehicle. Refer to Vehicle Lifting. 2. Support the transmission with a transmission jack.
3. Remove the nut retaining the transmission mount to the transmission support. 4. Raise the rear
of the transmission.
5. Remove the bolts and the nuts retaining the transmission support to the frame. (15 series)
6. Remove the bolts and the nuts retaining the transmission support to the frame. (25/35 series) 7.
Remove the transmission support from the frame.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Cross-Member > Component Information >
Service and Repair > Engine Front Crossmember Replacement (4WD) > Page 10412
1. Install the transmission support to the frame. (15 series)
2. Install the transmission support to the frame. (25/35 series)
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the bolts and the nuts in order to retain the transmission support to the frame.
Tighten the nuts to 95 N.m (70 lb ft).
4. Lower the rear of the transmission.
5. Install the transmission mount to the transmission support. 6. Install the nuts in order to retain
the transmission mount to the transmission support.
Tighten the nuts to 50 N.m (36 lb ft).
7. Remove the transmission jack. 8. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Front Steering Knuckle > Component Information
> Service and Repair
Front Steering Knuckle: Service and Repair
Steering Knuckle Replacement
Tools Required ^
J43631 Ball Joint Separating Tool
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Remove the tire and wheel.
3. Disconnect the Real Time Damping (RTD) link rod from the sensor, if equipped. 4. Unload the
torsion bars. 5. Remove the wheel hub and bearing assembly. 6. Disconnect the outer tie rod to the
steering knuckle. 7. Remove the brake hose bracket retaining bolt from the steering knuckle.
8. Remove the upper control arm retaining nut and separate the upper ball joint from the steering
knuckle (2) using the J43631 (1).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Front Steering Knuckle > Component Information
> Service and Repair > Page 10416
9. Remove the lower control arm retaining nut. Separate the lower ball joint from the steering
knuckle (2) using the J43631(1).
10. Remove the steering knuckle.
Installation Procedure
1. Clean all grease and contaminants from the tapered section and the threads of the upper ball
joint, the lower ball joint, and the tie rod end. 2. Clean and inspect the taper holes and the mounting
surfaces of the steering knuckle. If any of the tapered holes are elongated, out of round, or
damaged, replace the steering knuckle.
3. Install the steering knuckle.
Notice: Refer to Fastener Notice in Service Precautions.
4. Connect the lower ball joint to the steering knuckle and install the retaining nut.
Tighten the lower control arm retaining nut to 100 Nm (74 ft. lbs.).
5. Connect the upper ball joint to the steering knuckle and install the retaining nut.
Tighten the upper control arm retaining nut to 50 Nm (37 ft. lbs.).
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Front Steering Knuckle > Component Information
> Service and Repair > Page 10417
6. Install the brake hose and the bracket retaining bolt to the steering knuckle
Tighten the bolt to 9 Nm (80 inch lbs.).
7. Connect the outer tie rod to the steering knuckle. 8. Install the wheel hub and bearing assembly.
9. Connect the RTD link rod to the sensor, if equipped.
10. Install the tire and wheel. 11. Load the torsion bars. 12. Align the vehicle. 13. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Lateral Stabilizer Rod > Component Information
> Specifications
Lateral Stabilizer Rod: Specifications
Track Bar Bolt ......................................................................................................................................
.................................................. 105 Nm (77 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Lateral Stabilizer Rod > Component Information
> Specifications > Page 10421
Lateral Stabilizer Rod: Service and Repair
Track Bar Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting. 2. Support the rear axle.
3. Remove the park brake cable retaining clips to remove the parking brake cable from the track
bar.
4. Remove the track bar retaining nuts. 5. Remove the track bar retaining bolts. 6. Remove the
track bar from the vehicle.
Installation Procedure
1. Install the track bar to the vehicle. 2. Install the track bar retaining bolts.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Lateral Stabilizer Rod > Component Information
> Specifications > Page 10422
Notice: Refer to Fastener Notice in Service Precautions.
Important: Do not tighten the bolts unless the suspension is at the curb height position.
3. Install the track bar retaining nuts.
Tighten the bolts to 105 Nm (77 ft. lbs.).
4. Install the parking brake cable and retaining clips to the track bar. 5. Remove the rear axle
support. 6. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Specifications
Suspension Control Module: Specifications
Electronic Suspension Control Module to Bracket
.............................................................................................................................. 1.6 Nm (14 inch
lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Diagrams > C1
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Diagrams > C1 > Page 10429
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Diagrams > C1 > Page 10430
Suspension Control Module: Diagrams C3
Suspension Control Module - C3
Part 1 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Diagrams > C1 > Page 10431
Part 2 of 2
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Relays and Modules - Suspension > Suspension
Control Module > Component Information > Diagrams > Page 10432
Suspension Control Module: Service and Repair
Electronic Suspension Control Module Replacement (Tahoe/Yukon/Escalade)
Removal Procedure
1. Remove the right side interior trim panel. 2. Disconnect the electrical connectors from the
module.
3. Remove the screw. 4. Slide the module from the bracket and remove the module from the
vehicle.
Installation Procedure
1. Install the module to the vehicle by sliding the module into the bracket.
Notice: Refer to Fastener Notice in Service Precautions.
2. Install the screw.
Tighten the screw to 1.6 Nm (14 inch lbs.).
3. Connect the electrical connectors to the module. 4. If you are replacing the module you must
recalibrate the module by performing the following procedure:
^ Connect the scan tool to the Data Line Connector (DLC).
^ Turn the ignition ON with the engine OFF.
^ Proceed per the instructions on the scan tool readout.
5. Install the right side interior trim panel.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Specifications
Ride Height Sensor: Specifications
Front Position Sensor Link Bracket Bolt
................................................................................................................................................. 9 Nm
(80 inch lbs.) Front Position Sensor Mounting Bolt
.................................................................................................................................................. 12 Nm
(106 inch lbs.) Rear Position Sensor Link Bracket Bolt
................................................................................................................................................... 25
Nm (18 ft. lbs.) Rear Position Sensor Mounting Bolt
................................................................................................................................................... 12
Nm (106 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Diagrams > LF
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 10439
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 10440
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Diagrams > LF > Page 10441
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Service and Repair > Front Position Sensor Link Assembly
Replacement - Electronic Suspension
Ride Height Sensor: Service and Repair Front Position Sensor Link Assembly Replacement Electronic Suspension
Front Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the mounting bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the mounting bracket.
2. Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Ride
Height Sensor, Suspension Control > Component Information > Service and Repair > Front Position Sensor Link Assembly
Replacement - Electronic Suspension > Page 10444
Ride Height Sensor: Service and Repair Rear Position Sensor Link Assembly Replacement Electronic Suspension
Rear Position Sensor Link Assembly Replacement - Electronic Suspension
Tools Required ^
J38185 Spring Hose Clamp Pliers
Removal Procedure
Important: Do not attempt to pry the link rod from the Real Time Damping (RTD) ball stud. If the link
rod needs to be replaced or disconnected you must use the following procedure.
1. Remove the RTD sensor from the vehicle.
2. While supporting the sensor lever by hand, twist the link rod to remove it from the ball stud. 3.
Remove the link rod from the frame bracket ball stud.
Installation Procedure
1. Using the J38185 install to link rod to the ball stud on the sensor lever and the frame bracket. 2.
Install the RTD sensor to the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Steering
Angle Sensor > Component Information > Locations
Steering Wheel Speed/Position Sensor
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Steering
Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Steering
Angle Sensor > Component Information > Diagrams > Steering Wheel Speed/Position Sensor - W/ RTD > Page 10450
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Steering
Angle Sensor > Component Information > Diagrams > Page 10451
Steering Angle Sensor: Service and Repair
Steering Wheel Position Sensor Replacement
Removal Procedure
1. Set the front wheels in the straight-ahead position. Set the steering wheel in the LOCKED
position. 2. Disable the Supplemental Inflatable Restraint (SIR).
3. Remove the nut and the bolt (1) from the upper intermediate shaft connection and slide the
intermediate steering shaft down.
4. Remove the position sensor connector by using a suitable tool in order to pull the connector
down around the right side of the steering column for
accessibility.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
5. Remove the position sensor and bearing assembly from the steering column jacket by pulling the
assembly straight out. 6. Remove the position sensor from the clips in the bearing assembly.
Installation Procedure
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension > Steering
Angle Sensor > Component Information > Diagrams > Page 10452
1. Install the position sensor into the bearing assembly.
Important: Do not apply force to the sensor and the bearing in a sideways direction.
2. Install the bearing into the steering column jacket.
2.1. Align the notches on the bearing and the column jacket.
2.2. Seat the bearing fulling into the jacket.
3. Connect the position sensor connector.
Notice: Refer to Fastener Notice in Service Precautions.
4. Slide the shaft up to install the bolt and the nut (1) to the upper intermediate shaft to steering
column connection.
Tighten the upper intermediate shaft connection to 47 Nm (35 ft. lbs.).
5. Enable the SIR system.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Sensors and Switches - Suspension >
Suspension Control Pressure Sensor/Switch > Component Information > Service and Repair
Suspension Control Pressure Sensor/Switch: Service and Repair
"For information regarding this component please refer to air dryer suspension control service and
repair"
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Stabilizer Bar, Sway Control > Stabilizer Link >
Component Information > Technical Service Bulletins > Suspension - Revised Stabilizer Link Service/Torque
Stabilizer Link: Technical Service Bulletins Suspension - Revised Stabilizer Link Service/Torque
Bulletin No.: 05-03-08-006
Date: April 12, 2005
SERVICE MANUAL UPDATE
Subject: Revised Stabilizer Shaft Link Replacement Procedure and Fastener Tightening
Specifications
Models: 1999-2005 Chevrolet and GMC Full Size Pickup and Utility Models 2003-2005 HUMMER
H2
This bulletin is being issued to revise the Stabilizer Shaft Link Replacement Procedure and
Fastener Tightening Specifications in the Front Suspension sub-section of the Service Manual.
Please replace the current information in the Service Manual with the following information.
The following information has been updated within SI. If you are using a paper version of this
Service Manual, please make a reference to this bulletin on the affected page.
The following revision affects both the Fastener Tightening Specifications and the Stabilizer Shaft
Link Replacement procedure.
Pickup and Utility Models : Stabilizer Shaft Link Nuts - 10 Nm (89 lb in)
Continue tightening the nut until 2 to 4 threads protrude above the nut.
H2 : Stabilizer Shaft Link Nuts - 14 Nm (124 lb in)
Continue tightening the nut until 2 to 4 threads protrude above the nut.
The following Notice has been added to the Stabilizer Shaft Link Replacement procedure.
Note:
To avoid stabilizer shaft damage due to loss of clamp load, the threads of the link bolt must
protrude 2 to 4 threads above the nut after the specified torque is achieved.
Disclaimer
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Stabilizer Bar, Sway Control > Stabilizer Link >
Component Information > Technical Service Bulletins > Page 10461
Stabilizer Link: Specifications
The content of this article reflects the changes identified in TSB 05-03-08-006.
Front
Stabilizer Shaft Link Nuts ....................................................................................................................
............................................. 10 Nm (89 inch lbs.) Continue tightening the nut until 2-4 threads
protrude above the nut.
Rear
Stabilizer Shaft Link Nuts ....................................................................................................................
................................................. 65 Nm (48 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Stabilizer Bar, Sway Control > Stabilizer Link >
Component Information > Technical Service Bulletins > Page 10462
Stabilizer Link: Service and Repair
The content of this article reflects the changes identified in TSB 05-03-08-006.
Stabilizer Shaft Link Replacement
Removal Procedure
1. Raise and support the vehicle. Refer to Vehicle Lifting.
2. Remove the stabilizer shaft nut (1) from the link bolt. 3. Remove the stabilizer shaft link bolt (3).
4. Remove the stabilizer shaft link insulators and spacers (2). 5. Inspect all of the parts for wear
and damage.
Installation Procedure
1. Install the stabilizer shaft link insulators and spacers (2). 2. Install the stabilizer shaft link bolts
(3).
Notice: Refer to Fastener Notice in Service Precautions.
3. Install the stabilizer shaft nut (1) to the link bolt.
Tighten the nut to 10 Nm (89 inch lbs.). Continue tightening the nut until 2-4 threads protrude
above the nut.
4. Remove the safety stands. 5. Lower the vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Air Dryer, Suspension Control > Component Information > Service and Repair
Air Dryer: Service and Repair
Automatic Level Control Air Dryer and Pressure Sensor Replacement
Removal Procedure
1. Remove the automatic level control air compressor from the vehicle. 2. Clean the area around
the connection of the automatic level control air dryer to the automatic level control air compressor
body. 3. Disconnect the electrical connector from the pressure sensor. 4. Remove the air
dryer/pressure sensor assembly retaining screw. 5. Push the air dryer/pressure sensor assembly in
while rotating the air dryer/pressure sensor assembly clockwise until the assembly detaches from
the
automatic level control air compressor body.
6. Remove the automatic level control air dryer from the automatic level control air compressor.
Installation Procedure
1. Install the automatic level control air dryer to the automatic level control air compressor. 2. Push
the air dryer/pressure sensor assembly in while rotating the air dryer/pressure sensor assembly
counterclockwise until the assembly attaches
to the automatic level control air compressor body.
3. Install the air dryer/pressure sensor assembly retaining screw. 4. Connect the electrical
connector to the pressure sensor. 5. Install the automatic level control air compressor to the
vehicle.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Air Line, Suspension Control > Component Information > Specifications
Air Line: Specifications
Air Line Tube Repair Nut .....................................................................................................................
................................................. 8 Nm (70 inch lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Air Line, Suspension Control > Component Information > Specifications > Page 10470
Air Line: Service and Repair
Air Line Tubing Repair
1. Locate the leaking area with soap and water or a stethoscope.
2. Cut and remove the leaking line (2) section. 3. Remove the plastic retainer pin from one of the
nuts. 4. Slide the air line tube onto the nut until the line bottoms in the rubber seal (5).
Notice: Refer to Fastener Notice in Service Precautions.
5. Hold the air line tube in position.
Tighten the air line tube repair nut to 8 Nm (70 inch lbs.).
6. Install the air line tube to the other end of the coupling. 7. Repeat Steps 3 through 5.
Important: Ensure that the repaired air line tube is secured in a location where the line is not
pinched, or kinked, and will not contact the exhaust system.
8. Install the air line tube to the vehicle. 9. Inflate the real time damping level control system and
inspect for leaks.
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Compressor/Pump, Suspension Control > Component Information > Specifications
Compressor/Pump: Specifications
Air Compressor to Frame Nuts ............................................................................................................
..................................................... 15 Nm (11 ft. lbs.)
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Compressor/Pump, Suspension Control > Component Information > Specifications > Page 10474
Chevrolet K Tahoe 4wd Workshop Manual (V8-5.3L VIN T (2002))
Chevrolet Workshop Manuals > Steering and Suspension > Suspension > Suspension Control ( Automatic - Electronic ) >
Compressor/Pump, Suspension Control > Component Information > Diagrams > Diagram Information and Instructions
Compressor/Pump: Diagram Information and Instructions
Utility/Van Zoning
All grounds, in-line connectors, pass-through grommets, and splices have identifying numbers that
correspond to where they are located in the vehicle. The table explains the numbering system.
Electrical Symbols
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Electrical Symbols Part 1
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Electrical Symbols Part 2
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Electrical Symbols Part 3
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Electrical Symbols Part 4
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Compressor/Pump: Diagnostic Aids
Basic Knowledge Required
Without a basic knowledge of electricity, it will be difficult to use the diagnostic procedures
contained. You should understand the basic theory of electricity and know the meaning of voltage
(volts), current (amps) and resistance (ohms). You should be able to read and understand a wiring
diagram, as well as understand what happens in a circuit with an open or a shorted wire.
Checking Aftermarket Accessories
Do not connect aftermarket accessories into the following circuits:
CAUTION: Refer to SIR Handling Caution in Service Precautions.
- SIR circuits, all such circuits are indicated on circuit diagrams with the SIR symbol.
NOTE: Refer to OBD II Symbol Description Notice in Service Precautions.
- OBD II circuits, all such circuits are indicated on circuit diagrams with the OBD II symbol.
Always check for aftermarket accessories (non-OEM) as the first step in diagnosing electrical
problems. If the vehicle is so equipped, disconnect the system to verify that these add-on
accessories are not the cause of the problems.
Possible causes of vehicle problems related to aftermarket accessories include:
- Power feeds connected to points other than the battery
- Antenna location
- Transceiver wiring located too close to vehicle electronic modules or wiring
- Poor shielding or poor connectors on antenna feed line
- Check for recent service bulletins detailing installation guidelines for aftermarket accessories.
Inducing Intermittent Fault Conditions
In order to duplicate the customer's concern, it may be necessary to manipulate the wiring harness
if the malfunction appears to be vibration related. Manipulation of a circuit can consist of a wide
variety of actions, including:
- Wiggling the harness
- Disconnecting a connector and reconnecting
- Stressing the mechanical connection of a connector
- Pulling on the harness or wire in order to identify a separation/break inside the insulation
- Relocating a harness or wires
All these actions should be performed with some goal in mind. For instance, with a scan tool
connected, wiggling the wires may uncover a faulty input to the control module. The snapshot
option would be appropriate here. Refer to Scan Tool Snapshot Procedure. See: General Electrical
Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
You may need to load the vehicle in order to duplicate the concern. This may require the use of
weights, floor jacks, jackstands, frame machines, etc. In these oases you are attempting to
duplicate the concern by manipulating the suspension or frame. This method is useful in finding
harnesses that are too short and their connectors pull apart enough to cause a poor connection. A
DMM set to Peak Min/Max mode and connected to the suspect circuit while testing can yield
desirable results. Refer to Testing for Electrical Intermittents. See: Diagrams/Diagnostic Aids
Certainly, using the senses of sight, smell, and hearing while manipulating the circuit can provide
good results as well.
There may be instances where circuit manipulation alone will not meet the required criteria for the
fault condition to appear. In such cases it may be necessary to expose the suspect circuit to other
conditions while manipulating the harness. Such conditions would include high moisture conditions,
along with exceptionally high or low temperatures. The following discusses how to expose the
circuit to these kinds of conditions.
Salt Water Spray Some compounds possess the ability to conduct electricity when dissolved in
water such as ordinary salt. By mixing table salt with water in sufficient quantities, you can enhance
the conductive properties of water so that any circuit which may be sensitive to moisture will more
readily fail when liberally sprayed with this mixture.
Mixing 0.35 L (12 oz) of water with approximately 1 tablespoon of salt will yield a salt solution of 5
percent. Fill a normal spray bottle with this mixture. This mixture is sufficient to enhance the water's
own conductivity. This may cause the circuit to fail more easily when sprayed. Once the mixture is
completed, spray the suspect area liberally with the solution. Then, while monitoring either a scan
tool or DMM, manipulate the harness as discussed previously.
High Temperature Conditions
TOOLS REQUIRED
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J 25070 Heat Gun
If the complaint tends to be heat related, you can simulate the condition using the J 25070.
Using the heat gun, you can heat up the suspected area or component. Manipulate the harnesses
under high temperature conditions while monitoring the scan tool or DMM to locate the fault
condition.
The high temperature condition may be achieved simply by test driving the vehicle at normal
operating temperature. If a heat gun is unavailable, consider this option to enhance your diagnosis.
This option does not allow for the same control, however.
Low Temperature Conditions Depending on the nature of the fault condition, placing a fan in front
of the vehicle while the vehicle is in the shade can have the desired effect.
If this is unsuccessful, use local cooling treatments such as ice or a venturi type nozzle (one that
provides hot or cold air). This type of tool is capable of producing air stream temperatures down to
-18°C ( 0°F) from one end and 71°C (160°F) from the other. This is ideally suited for localized
cooling needs.
Once the vehicle, component, or harness has been sufficiently cooled, manipulate the harness or
components in an effort to duplicate the concern.
Measuring Frequency
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the frequency of a signal.
IMPORTANT: Connecting the DMM to the circuit before pressing the Hz button will allow the DMM
to autorange to an appropriate range.
1. Apply power to the circuit. 2. Set the rotary dial of the DMM to the V (AC) position. 3. Connect
the positive lead of the DMM to the circuit to be tested. 4. Connect the negative lead of the DMM to
a good ground. 5. Press the Hz button on the DMM. 6. The DMM will display the frequency
measured.
Measuring Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure measures the voltage at a selected point in a circuit.
1. Disconnect the electrical harness connector for the circuit being tested, if necessary. 2. Enable
the circuit and/or system being tested. Use the following methods:
- Turn ON the ignition, with the engine OFF.
- Turn ON the engine.
- Turn ON the circuit and/or system with a scan tool in Output Controls.
- Turn ON the switch for the circuit and/or system being tested.
3. Select the V (AC) or V (DC) position on the DMM. 4. Connect the positive lead of the DMM to the
point of the circuit to be tested. 5. Connect the negative lead of the DMM to a good ground. 6. The
DMM displays the voltage measured at that point.
Measuring Voltage Drop
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure determines the difference in voltage potential between 2 points.
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1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 point of the circuit to be tested. 3. Connect the negative lead of the DMM to the other point of the
circuit. 4. Operate the circuit. 5. The DMM displays the difference in voltage between the 2 points.
Scan Tool Snapshot Procedure
Snapshot is a recording of what a control module on the vehicle was receiving for information while
the snapshot is being made. A snapshot may be used to analyze the data during the time a vehicle
condition is current. This allows you to concentrate on making the condition occur, rather than
trying to view all the data in anticipation of the fault. The snapshot contains information around a
trigger point that you have determined. Only a single data list may be recorded in each snapshot.
The Scan Tool has the ability to store 2 snapshots. The ability to record 2 snapshots allows
comparing hot versus cold and good versus bad vehicle scenarios. The snapshots are stored on a
'first in, first out' basis. If a third snapshot is taken, the first snapshot stored in the memory will be
lost.
Snapshots can be 1 of 2 types:
- Snapshot - taken from the Snapshot menu choice
- Quick Snapshot - taken from the Data Display soft key choice, does not contain DTC information
When a snapshot is taken, it is recorded on the memory card and may contain as many as 1200
frames of information. Because the snapshot is recorded onto the memory card, snapshots are not
lost if the Scan Tool is powered down.
The snapshot replay screen has a plot soft key that can be of great value for intermittent diagnosis.
The snapshot plot feature can help you to quickly determine if a sensor is outside of its expected
values by plotting three parameters at a time. The data will be displayed both graphically and
numerically showing the minimum and maximum values for all frames captured. This is helpful,
especially if the fault occurs only once and does not set a DTC.
Testing For a Short To Voltage
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedure tests for a short to voltage in a circuit.
1. Set the rotary dial of the DMM to the V (DC) position. 2. Connect the positive lead of the DMM to
1 end of the circuit to be tested. 3. Connect the negative lead of the DMM to a good ground. 4.
Turn ON the ignition and operate all accessories. 5. If the voltage measured is greater than 1 volt,
there is a short to voltage in the circuit.
Testing for Continuity
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures verify good continuity in a circuit.
With a DMM 1. Set the rotary dial of the DMM to the Ohm position. 2. Disconnect the power feed
(i.e. fuse, control module) from the suspect circuit. 3. Disconnect the load. 4. Press the MIN MAX
button on the DMM. 5. Connect one lead of the DMM to one end of the circuit to be tested. 6.
Connect the other lead of the DMM to the other end of the circuit. 7. If the DMM displays low or no
resistance and a tone is heard, the circuit has good continuity.
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With a Test Lamp
IMPORTANT: Only use the test lamp procedure on low impedance power and ground circuits.
1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2. Disconnect the
load. 3. Connect 1 lead of the test lamp to 1 end of the circuit to be tested. 4. Connect the other
lead of the test lamp to battery positive voltage. 5. Connect the other end of the circuit to ground. 6.
If the test lamp illuminates (full intensity), then the circuit has good continuity.
Testing For Electrical Intermittents
Perform the following procedures while wiggling the harness from side to side. Continue this at
convenient points (about 6 inches apart) while watching the test equipment.
- Testing for Short to Ground See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For Short to Ground
- Testing for Continuity See: General Electrical Diagnostic Procedures/Circuit Testing/Testing for
Continuity
- Testing for Short to Voltage See: General Electrical Diagnostic Procedures/Circuit Testing/Testing
For a Short To Voltage
If the fault is not identified, perform the procedure below using the MIN MAX feature on the DMM.
This feature allows you to manipulate the circuit without having to watch the DMM. The DMM will
generate an audible tone when a change is detected.
IMPORTANT: The J 39200 must be used in order to perform the following procedure since the J
39200 can monitor current, resistance or voltage while recording the minimum (MIN), and
maximum (MAX) values measured.
1. Connect the DMM to both sides of a suspected connector (still connected), or from one end of a
suspected circuit to the other. Refer to
Troubleshooting with a Digital Multimeter for information on connecting the DMM to the circuit. See:
General Electrical Diagnostic Procedures/Troubleshooting Tools/Troubleshooting With A Digital
Multimeter
2. Set the rotary dial of the DMM to the V (AC) or V (DC) position. 3. Press the range button of the
DMM in order to select the desired voltage range. 4. Press the MIN MAX button of the DMM. The
DMM displays 100 ms RECORD and emits an audible tone (beep).
IMPORTANT: The 100 ms RECORD mode is the length of time an input must stay at a new value
in order to record the full change.
5. Simulate the condition that is potentially causing the intermittent connection, either by wiggling
the connections or the wiring, test driving, or
performing other operations. Refer to Inducing an Intermittent Fault Condition. See: General
Electrical Diagnostic Procedures/Circuit Testing/Inducing Intermittent Fault Conditions
6. Listen for the audible Min Max Alert which indicates that a new minimum or maximum value has
been recorded. 7. Press the MIN MAX button once in order to display the MAX value and note the
value. 8. Press the MIN MAX button again in order to display the MIN value and note the value. 9.
Determine the difference between the MIN and MAX values.
- If the variation between the recorded MIN and MAX voltage values is 1 volt or greater an
intermittent open or high resistance condition exists. Repair the condition as necessary.
- If the variation between the recorded MIN and MAX voltage values is less than 1 volt an
intermittent open or high resistance condition does not exist.
Testing For Intermittent and Poor Connections
Most intermittent conditions are caused by faulty electrical connections or wiring. Inspect for the
following items:
- Wiring broken inside the insulation
- Poor connection between the male and female terminal at a connector-Refer to Testing for Proper
Terminal Contact for the specific procedure. See: General Electrical Diagnostic Procedures/Circuit
Testing/Testing For Proper Terminal Contact
- Poor terminal to wire connection-Some conditions which fall under this description are poor
crimps, poor solder joints, crimping over the wire insulation rather than the wire itself and corrosion
in the wire to terminal contact area, etc.
- Wire insulation which is rubbed through- This causes an intermittent short as the bare area
touches other wiring or parts of the vehicle.
- Refer to Inducing Intermittent Fault Conditions in order to duplicate the conditions required in
order to verify the complaint. See: General Electrical Diagnostic Procedures/Circuit
Testing/Inducing Intermittent Fault Conditions
- Refer to Testing for Electrical Intermittent for test procedures to detect intermittent open, high
resistance, short to ground, and short to voltage conditions. See: Diagrams/Diagnostic Aids
- Refer to Scan Tool Snapshot Procedure for advanced intermittent diagnosis. See: General
Electrical Diagnostic Procedures/Circuit Testing/Scan Tool Snapshot Procedure
Testing For Proper Terminal Contact
TOOLS REQUIRED
- J 42675 flatware Probe Adapter
- J 38125-B Terminal Repair Kit
It is important to test terminal contact at the component and any on-line connectors before
replacing a suspect component. Mating terminals must be
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inspected to ensure good terminal contact. A poor connection between the male and female
terminal at a connector may be the result of contamination or deformation.
Contamination may be caused by the connector halves being improperly connected. A missing or
damaged connector seal, damage to the connector itself, or exposing the terminals to moisture and
dirt can also cause contamination. Contamination usually in the underhood or underbody
connectors, leads to terminal corrosion, causing an open circuit or intermittently open circuit.
Deformation is caused by probing the mating side of a connector terminal without the proper
adapter, improperly joining the connector halves, or repeatedly separating and joining the
connector halves. Deformation, usually to the female terminal contact tang, can result in poor
terminal contact causing an open or intermittently open circuit.
Round Wire Connectors Follow the procedure below to test terminal contact of Metri-Pack or 56
series terminals. Refer to the J 38125-B or the J 38125-4 Instruction Manual for terminal
identification.
Follow the procedure below in order to test terminal contact. 1. Separate the connector halves. 2.
Visually inspect the connector halves for contamination. Contamination may result in a white or
green build-up within the connector body or
between terminals. This causes high terminal resistance, intermittent contact, or an open circuit. An
underhood or underbody connector that shows signs of contamination should be replaced in its
entirety: terminals, seals, and connector body.
3. Using an equivalent male terminal from the J 38125-B, test that the retention force is significantly
different between a good terminal and a suspect
terminal. Replace the female terminal in question.
Flat Wire (Dock and Lock) Connectors There are no serviceable parts for flat wire (dock and lock)
connectors on the harness side or the component side.
Follow the procedure below in order to test terminal contact. 1. Remove the component in question.
2. Visually inspect each side of the connector for signs of contamination. Avoid touching either side
of the connector as oil from your skin may be a
source of contamination as well.
3. Visually inspect the terminal bearing surfaces of the flat wire circuits for splits, cracks, or other
imperfections that could cause poor terminal
contact. Visually inspect the component side connector to ensure that all of the terminals are
uniform and free of damage or deformation.
4. Insert the appropriate adapter from the J 42675 on the flat wire harness connector in order to
test the circuit in question.
Testing For Short to Ground
NOTE: Refer to Test Probe Notice in Service Precautions.
The following procedures test for a short to ground in a circuit.
With a DMM 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Set the rotary dial of the DMM to the Ohm position. 4. Connect 1 lead of the
DMM to 1 end of the circuit to be tested. 5. Connect the other lead of the DMM to a good ground. 6.
If the DMM does NOT display infinite resistance (OL), there is a short to ground in the circuit.
With a Test Lamp 1. Remove the power feed (i.e. fuse, control module) from the suspect circuit. 2.
Disconnect the load. 3. Connect 1 lead of the test lamp to battery positive voltage. 4. Connect the
other lead of the test lamp to 1 end of the circuit to be tested. 5. If the test lamp illuminates, there is
a short to ground in the circuit.
Fuse Powering Several Loads 1. Review the system schematic and locate the fuse that is open. 2.
Open the first connector or switch leading from the fuse to each load. 3. Connect a DMM across
the fuse terminals (be sure that the fuse is powered).
- When the DMM displays voltage the short is in the wiring leading to the first connector or switch.
- If the DMM does not display voltage refer to the next step.
4. Close each connector or switch until the DMM displays voltage in order to find which circuit is
shorted.
Circuit Testing
The Circuit Testing contains the following diagnostic testing information. Using this information
along with the diagnostic procedures will identify the cause of the electrical malfunction.
- Using Connector Test Adapters
- Probing Electrical Connectors
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- Troubleshooting with a Digital Multimeter
- Troubleshooting with a Test Lamp
- Using Fused Jumper Wires
- Measuring Voltage
- Measuring Voltage Drop
- Measuring Frequency
- Testing for Continuity
- Testing for Short to Ground
- Testing for a Short to Voltage
Probing Electrical Connectors
IMPORTANT: Always be sure to reinstall the connector position assurance (CPA) and terminal
position assurance (TPA) when reconnecting connectors or replacing terminals.
Frontprobe Disconnect the connector and probe the terminals from the mating side (front) of the
connector.
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Backprobe
IMPORTANT: Backprobe connector terminals only when specifically required in diagnostic procedures.
- Do not backprobe a sealed (Weather Pack(R)) connector, less than a 280 series Metri-Pack
connector, a Micro-Pack connector, or a flat wire (dock and lock) connector.
- Backprobing can be a source of damage to connector terminals. Use care in order to avoid
deforming the terminal, either by forcing the test probe too far into the cavity or by using too large
of a test probe.
- After backprobing any connector, inspect for terminal damage. If terminal damage is suspected,
test for proper terminal contact.
Do not disconnect the connector and probe the terminals from the harness side (back) of the
connector.
Troubleshooting With A Digital Multimeter
NOTE: Refer to Test Probe Notice in Service Precautions.
IMPORTANT: Circuits which include any solid state control modules, such as the PCM, should only
be tested with a 10 megohm or higher impedance digital multimeter such as the J 39200.
The J 39200 instruction manual is a good source of information and should be read thoroughly
upon receipt of the DMM as well as kept on hand for future reference.
A DMM should be used instead of a test lamp in order to test for voltage in high impedance circuits.
While a test lamp shows whether voltage is present, a DMM indicates how much voltage is
present.
The ohmmeter function on a DMM shows how much resistance exists between 2 points along a
circuit. Low resistance in a circuit means good continuity.
IMPORTANT: Disconnect the power feed from the suspect circuit when measuring resistance with
a DMM. This prevents incorrect readings. DMMs apply such a small voltage to measure resistance
that the presence of voltages can upset a resistance reading.
Diodes and solid state components in a circuit can cause a DMM to display a false reading. To find
out if a component is affecting a measurement take a reading once, then reverse the leads and
take a second reading. If the readings differ the solid state component is affecting the
measurement.
Following are examples of the various methods of connecting the DMM to the circuit to be tested:
- Backprobe both ends of the connector and either hold the leads in place while manipulating the
connector or tape the leads to the harness for continuous monitoring while you perform other
operations or test driving. Refer to Probing Electrical Connectors. See: General Electrical
Diagnostic Procedures/Troubleshooting Tools/Probing Electrical Connectors
- Disconnect the harness at both ends of the suspected circuit where it connects either to a
component or to other harnesses.
- If the system that is being diagnosed has a specified pinout or breakout box, it may be used in
order to simplify connecting the DMM to the circuit or for testing multiple circuits quickly.
Troubleshooting With A Test Lamp
TOOLS REQUIRED
J 34142-B 12 V Unpowered Test Lamp
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NOTE: Refer to Test Probe Notice in Service Precautions.
A test lamp can simply and quickly test a low impedance circuit for voltage.
The J 34142-B is Micro-Pack compatible and comprised of a 12-volt light bulb with an attached pair
of leads.
To properly operate this tool use the following procedure.
1. Attach one lead to ground. 2. Touch the other lead to various points along the circuit where
voltage should be present. 3. When the bulb illuminates, there is voltage at the point being tested.
Using Connector Test Adapters
NOTE: Do not insert test equipment probes into any connector or fuse block terminal. The diameter
of the test probes will deform most terminals. A deformed terminal can cause a poor connection,
which can result in system failures. Always use the J 35616-A Connector Test Adapter Kit or the J
42675 Flat Wire Probe Adapter kit in order to frontprobe terminals. Do not use paper clips or other
substitutes as they can damage terminals and cause incorrect measurements.
Using Fused Jumper Wires
TOOLS REQUIRED
J 36169-A Fused Jumper Wire
IMPORTANT: A fused jumper may not protect solid state components from being damaged.
The J 36169-A includes small clamp connectors that provide adaptation to most connectors without
damage. This fused jumper wire is supplied with a 20-A fuse which may not be suitable for some
circuits. Do not use a fuse with a higher rating than the fuse that protects the circuit being tested.
Fuses
Circuit Protection - Fuses
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Fuse Types Part 1
Fuse Types Part 2
The fuse is the most common method of an automotive wiring circuit protection. Whenever there is
an excessive amount of current flowing through a circuit the fusible element will melt and create an
open or incomplete circuit. Fuses are an one time protection device and must be replaced each
time the circuit is overloaded. To determine if a fuse is open, remove the suspected fuse and
examine the element in the fuse for an open (break). If not broken, also check for continuity using a
DMM or a continuity tester. If the element is open or continuity is suspect, replace the fuse with one
of equal current rating.
Circuit Breakers
A circuit breaker is a protective device that is designed to open the circuit when a current load is in
excess of the rated breaker capacity. If there is a short or other type of overload condition in the
circuit, the excessive current will open the circuit between the circuit breaker terminals. Two types
of circuit breakers are used.
Circuit Breaker: This type opens when excessive current passes through it for a period of time. It
closes again after a few seconds, and if the cause of the high current is still present, it will open
again. The circuit breaker will continue to cycle open and closed until the condition causing the high
current is removed.
Positive Temperature Coefficient (PTC) Circuit Breaker: This type greatly increases its resistance
when excessive current passes through it. The excessive current heats the PTC device, as the
device heats its resistance increases. Eventually the resistance gets so high that the circuit is
effectively open. Unlike the ordinary circuit breaker the PTC unit will not reset until the circuit is
ope